INDUSTRIAL AND ENGINEERING CHEMISTRY
November. 1928
124.5
Importance of Temperature and Humidity Control in Rubber Testing I-Stress-Strain REPORT OF
T H E PHYSICAL ?%STING COMMITTEE OF
and Tensile Properties
DIVISION OF RUBBER CHEMISTRY
I
N OCTOBER, 1926, R . P. Dinsmore, chairman of the Rubber Division of the AMERICAN CHEMICAL SOCIETY, appointed a Physical Testing Committee to investigate the effect of variables such as temperature and relative humidity upon the physical properties of rubber. This committee was continued by Harry I,. Fisher, present chairman of the Rubber Division. The committee chose the problem of determining the importance of controlling atmospheric temperature and relative humidity while conditioning rubber test samples a t various stages of preparation and testing. This report deals with the first study made-that of the effect of the above two variables on the stressstrain and tensile properties of rubber. In reading this report it should be kept in mind that the problem of this committee is t o determine the effect of variables on the physical properties of rubber so that we may know the relative importance of controlling the factors involved. I t was not intended to make this work include the relative value of specific tests for particular purposes or to become a research directed towards the development of new tests. It has been the intent t o limit the work of the committee t o the refinement of tests widely used and considered as routine and standard, and not to include development of new tests or work concerning broader lines of research. I t is, however, hoped that in the future the work of this or another committee can be broadened to include fundamental research problems as well as specific work such as the present committee has undertaken. We believe that the work done demonstrates the desirability of carrying on cooperative investigations of this nature and hope that this committee is made a permanent institution of the Rubber Division with such changes in personnel as are necessary continually t o broaden and improve the work. This report will raise many questions and point out several possible lines of research, but the committee has tried t o stick to its job of determining the relative importance of controlling temperature and relative humidity in relation to stress-strain and tensile properties. The work has been carried out a t the Bureau of Standards a t Washington by F. E. Rupert as a research associate under the direction of the committee. The Bureau of Standards has contributed its facilities and to cover the expenditures of the committee for the first year each company represented by the members of the committee contributed $650. The Rubber Association of America is handling the finances of the committee for the present year, which amounts to $6000 and includes the appropriation of the Firestone Tire and Rubber Company. As the committee has needed special apparatus different companies have loaned machines. which have included a Scott tensile tester and U . s. abrasion machine from the Henry L. Scott Company, and a Grasselli abrader from the Grasselli Chemical Company.
Recommendation The undersigned committee recommends that: (1) Mixed stock prior to curing be conditioned for not less than 24 nor more than 28 hours a t an absolute humidity of 5 24 grains of water per cubic foot of dry air (0 012 gram of moisture per liter) and cured stock prior to testing be conditioned for not less than 24 hours at 82" * 2" F. (27.8' C.) and 45 per cent relative humidity * 3 per cent. (2) The testing room be maintained a t 82' =t2OF. (27.8"C.). ( 3 ) The time between removing samples from the conditioning cabinets and curing or testing be not more than 2 hours.
OF T H E
AMERICANCHEMICAL
SOCIETY
The temperature of the,whole testing room should be controlled closely. I t is not necessary, however, t o control the humidity of the entire room. Cabinets located in the room, humidified with the proper saturated salt solution or sulfuric acid solution, will produce the recommended conditions. The testing room temperature of 82" F. (27.8' C.) is chosen because it can be maintained in the majority of laboratories, with the exception of a few weeks in summer, without the use of refrigeration. The humidity conditions of 5.24 grains of water per cubic foot of dry air (0.012 gram of moisture per liter) and 45 per cent relative humidity a t 82 O F. (27.8' C.) are both equivalent t o 65 per cent relative humidity at 70" F. (21.1' C.), which are standard conditions for testing fabric. Those not able t o equip t o control these two factors should record both temperature and relative humidity during both aging periods-that is, between mixing and curing, and between curing and testing-so that later they will be able to prove to themselves the importance of temperature and humidity in connection with all laboratory work, especially with that which is t o be published.
Abstract The investigation has proved that variations in temperature wnich may occur from day t o day in an uncontrolled testing room may affect the physical tests to as great a degree as a 25 t o 40 per cent change in the time of cure, while relative humidity affects the results to only a minor degree. Furthermore, variations in the absolute humidity of the room in which the unvulcanized rubber is stored between the time of mixing and the time of curing may affect the tensile strength and modulus of rubber compounds to as great a degree as does the temperature after curing. It is therefore apparent that laboratory tests which are conducted under uncontrolled conditions of temperature and humidity may give highly erroneous results and may even give misinformation which is worse than no information a t all. The committee therefore recommends that mixed stock prior t o curing and cured stock prior to testing be conditioned for not less than 24 nor more than 28 hours a t 82" 2" F. (27.8"C.) and 45 3 per cent relative humidity and that the testing room be main2' F. If a temperature of 82' F. cannot be maintained a t 82 ,. tained for conditioning the mixed stock prior to curing, the committee recommends a relative humidity corresponding t o the temperature used which gives an absolute humidity equal to that obtained under the former conditions-namely, 5.24 grains of water per cubic foot of dry air (0.012 gram moisture per liter). The temperature of the testing room should be controlled within the above-stated limits, but it is not necessary to control the humidity of the entire room. A small conditioning cabinet in which the standard humidity is maintained has been found to be sufficient. An investigation of the effect of variations and relative humidity before miving showed only negligible differences in tensile and stress-strain properties, making it unnecessary to use more than ordinary care in storing rubber and compounding ingredients. The committee wishes t o point out that by controlling temperature and relative humidity only two of the many variables in rubber testing will be eliminated. True, these are two very important factors, but many others just as important were reported by
*
*
*
INDUSTRIAL A N D ENGINEERING CHEMISTRY
1246
EQUILIBRIUM OF VULCANIZED WITH O%AND 100%REL.HUM. I
I
1
T E S T P I E C E S EXPOSED IN D E S I C C A T O R OVER CONC H z S 0 4 A N D WATER I
2
3
4
DAYS
5
6
7
EXPOSURE
1
8
CHART I
the Physical Testing Committee of the Division of Rubber Chemistry in 1925.’ Before consistent results can be obtained all the variables will have to be controlled and before agreement between laboratories can be realized, standard procedures will have to be adopted. The methods are described in detail in the following report and the results are given in the accompanying tables and charts. The work required several thousand tests under varying conditions of humidity, temperature, and periods of exposure. EXPERIMENTAL
The purpose of this investigation is to determine the effect of atmospheric variations in temperature and relative humidity on the phyqical properties of rubber. in order that the importance of controlling these variables during testing may be established. The effect of these variables has been of considerable interest, although not much work has been done on the effect of the two variables in combination. The moisture content of sheets and crepe in reference to the control of mold and rust, and the effect of various periods of time and temperatures of soaking on the rate of cure of dried sheets has been investigated by Whitby.2
A study of the effectof the temperature of the testing room upon the physical properties of vulcanized rubber was made by n’ormeleya and by Tener, Kingsbury, and Holt.4 Stevens6 studied the effect of temperature previous to testing. StringfieIda investigated the effect of humidity both before and after curing. T h e physical properties of vulcanized compounds a t various temperatures have been recorded by Van Rossem and Van der Meyden.’ The present investigation ic: divided into two distinct phasesnamely, the effect of temperature and relative humidity upon the vulcanized samples subsequent to vulcanization and during tcsting (pages 1246 to 1259), and the effect of thesesame variablessubsequent to milling but prior to vulcanization (pages 12-19to 1273). Since the purpose of the investigation is to determine the importance of controlling temperature and relative humidity during the preparation and testing of specimens, and not the effect of these variables with any special compounds or ingredients, the five compounds given in Table I were chosen. They represent types of formulas in general use in the tire industry-a laboratory test compound, two high-grade gum tire carcass compounds, and two high-grade tread compounds. This selection provides materials for the study s f the effect of temperature and relative humidity upon compounds of high and low rubber content, upon compounds containing two widely different types of organic accelerators, and upon compounds using varying amounts of common softeners. This investigation includes only the stress-strain and tensile properties of the vulcaniLed compounds. Table I-Teat INGREO~ENT Smoked sheets Zinc oxide Sulfur Carbon black Di-o-tolylguanidine Mercaptobe~izothiazole Stearic acid Mineral rubber Pine t a r
Total
100.0 5.0 3.0
100.0 5.0 3.0
0.75
0.75
...
... ... ...
5.0
... ...
0.5 0.5 5.0
100.0 5.0 3.5 40.0 1.25
...
...
5,O
... ---_-. . .
... -_
2.0 ___
108.76
114.0
156.75
113 75
100 0 5.0 3.5 40.0
...
1.0 3.0
...
2.0 __ 154.5
of T e m p e r a t u r e a n d Relative H u m i d i t y S u b s e q u e n t to Vulcanization b u t Prior t o T e s t i n g PROCEDURE-The effect of temperature and relative humidity after curing but prior to and during testing was first investigated. In order to secure uniformity of ingredients in the five com“Rubber Industry.” p. 246 (1914). Bur. Standards, Tech. Paper 364. 6 J. Soc. Chem. I n d . , Si’, 280T (1918). 6 I N U .END.C H B M .17, , 883 (1925). 7 Kolloid.Z., 39, 69 (1926); Kaulschuk, Heft 13 (December, 1927). 8
I N D RNC). CHRM.,17, 535 (1925).
(1920).
I- ISMIN@ 2 8 7 O
.I
... ... ...
100.0 5.0 3.0
Part I-Effect
a ”Plantation Rubber a n d Testing of Rubber,” pp. 163, 177, 183, 289
3 - 4 5 1 .
Formulas
STOCK1 STOCK2 STOCK3 STOCK4 STUCK5
4
1
Vol. 20, No. 11
E - 4 0 , . 3- 60 Y
I* II
P E R C E N T ELONGATION
CHART 2
INDUSTRIAL AND ENGINEERING CHENISTRY
November, 1928
\
f
I
2800
1
' .
~-
I
1247
I
,
I
250'\
h
~
-L
I
'
0
'
I
'\\
I
'., 4
\
240Q
TEMP
'-.,
Box I HUMIDITY OY0 Acid
c.
%
5
Concd Concd Concd Concd. Concd.
25 15 35 45
Sp gr b
Box I1 HUMIDITY 20V0 Acid
Sp gr
% 1 84 1 84 1 84 1 81 1 84
57 58 58 59 59
BOY 111 HUMIDITY 40% Acid
Sp gr
1 47 1 47 1 48 1 48 1 49
47 48 48 49 50
5 0 5 0 0
1 37 1 37 1 38 1 38 1 39
Figures obtained from d a t a by Wilson, J. IND. ENG.CHEM.,13, 326 (1921). b All specific gravities a t 25" C.
a
Acld
Sp gr
70
% 5 0 5 0 5
Box I V HuhiInrTY 607,
37 38 38 39 39
Box V HUMIDITY 80% Acid
Sp gr
70 5
0
5 0
5
1 28 1 28 1 29 1 29 1 30
26 27 27 27 '28
5
0 3 8
0
Box VI HUMIDITY 100% Acld
Sp gr.
% 19 19 19 195 1 20
1 1 1 1
0 0 0 0
0 0 0 0
0 0
100 100 100 1 00 100
Vol. 20, No. 11
INDUSTRIAL A N D ENGINEERING CHEMISTRY
1248
'ECT OF FIGURES
EFFECT OF RELATIVE HUMIDITY AFTER VULCANIZATION FIGURES ARE AV€RAGE OF THREE MIDDLE CURES AT FIVE TEMPERATURES 24000 ,
I
FORMULA
+
FULL LINES = FINAL TENSILES I - POO,%MODULUS 300 % M O D U L U S 3-4007, MODULUS 4 = 500 % M O D U L U S 5=600%flODULU5 6 - 700% NODULUS
pounds, sufficient quantities of all materials were set aside for use in the entire investigation. The rubber was taken from three different lots of selected smoked sheets. A bale of each was taken and these three bales were washed on a four-roll washer. After drying, the 600 pounds (272 4 kg.) of washed rubber were blended in a Banbury mixer. Previous to this blending, four 575-pound (261.1-kg.) batches of crude rubber were run through the Banbury mixer to insure elimination of all compounding materials from the mixing chamber. The accelerators were master-batched in the laboratory t o insure accurate weighing. The batches were of factory size (starting with 75 pounds (34.05 kg.) of rubber in each case) and were mixed on a 60-inch (152.7-cm.) mill. The milling of the five batches was done as
uniformly as possible, the first three requiring 22 minutes each while the two batches containing carbon black required 30 minutes each. After being sheeted off the mills the five batches remained on racks until calendered about 2 hours later. The stocks were calendered on a three-roll calender to a thickness of 0.125 inch, (3.18 mm.), cut into strips 4.5 inches (11.43 cm.) wide, and wound into clean 42-inch (lC6.7-cm.) liners. The rolls were rewound twice to cool the stock. The rolls of stock were stored for 24 hours before curing in a room in which the temperature was maintained within the limits 82" and 89" F. 127.8' and 31 7" C.). The vulcanization was carried out continuously in two pot presses. It required about 42 hours for completion, thus elimi-
INDUSTRIAL AND ENGINEERING CHEMISTRY
November, 1928
EFFECT OF RELATIVE HUMIDITY AFTER VULCANIZ ATlON
EFFECT OF TEMPERATURE AFTER VU LCA NIZAT1ON
FIGURES ARE AVERAGE OF T H R E E RIDDLE CURES AT F I V E T E M P E R A T U R E S
FIGURES ARE AVERAGE OF THREE MIDDLE CURES AT SIX HUMIDITIES
I= ZOO%MODULUS FULL L I N E S = FINAL T E N S I L E S Z = 30O%MODULUS 3 =400%MODULUS 4 ~ 5 0 0 % 10 5.600% (0
FULL L I N E S = F I N A L T E N S I L E S I =2 0 0 % PlODULUS 2;- 300%MODULUS 3=400%MODULUS 4 = 500% 10 5~600%
+AVERAGE
t
OF
15 2 5 3 5 45 5 TEMPERATURE I N DEGREES CHART 7
I
AVERAGE O F
AVERAGEOF
I 5
1249
AVERAGE O F
I
15 25 35 45 CENTIGRADE
nating, as far as possible, variation due to elapsed time between mixing and curing in the unvulcanized state. Stocks 1, 2, and 4 (Table 1) were vulcanized for 15 30, 15, 60, and 90 minutes a t 287" F. (142' C . ) , while stocks 3 and 5 were vulcanized 20. 40, 60 90, and 120 minutes at 259" F. (126" C.). These various periods of vulcanization provide for a range from an undercure to an overcure. Forty-eight test slabs of each stock were prepared a t each period of vulcanization to provide suffic i e n t material for the ~
' I
RELATKI
EFFECT OF HUMIDITY AFTER V U L C A N I Z AT I 0N I
I 3E00
,
I
I
,
I 3 2 ~ 0
F"ALTENs1LE5
2
LBS/IN l
12800
1 24cc
I
'
I
~
tests. . _
The mixing and vulcanization were done a t t h e p l a n t of the Fisk
slabs were packed with holland cloth b e t w e e n each slab and sent to the 3 5 ~. B u r e a u of Standards, 45Dc Washington, D C , where the conditioning and testing were done. Approximately a elapsed between KG5 / c M 1 -2 month the curing and the first
:&
25';30
~
1
IaVDL7STRIALAND ENCiWEERING CHBMISTRY
1250
moisture becomes negligible for practical purposes. (Chart 1) General practice in the indu-try is to age raw stock from 24 to 48 hours hetween curing and testing. Consequently the majority of the tests were made after a n exposure af 48 hours, although some &day tests were made to determine the maximum effect. All results shown are based on a 2-day exposure with the exception of Chart 11. Four specimens of each cure of each qtock were maintained for 2.days a t temperatures of 41°, 59'. 77". 859 and 113" F, (5", 15". 2.5'. 35'.and 45"C.).rcspect3vrlv, while being exposed to relative humidities of 0 . 2J, 63, 83, and 100 per c a t . I n addition to these test% four snrcimens of the middle cure of each ittock were exposed for 6 davs a t 0 . BO, and I00 per cent relative humidities. respectively, at each of the temperatures just named. An atmosphere of the desired rclative
high. '(Photographs 1 and 2 ) These wooden bonos were coated on the inside with paraffin to rrnder them air-tight, and were provided with trays 15 by 14 inches (38.1 by 35.6 cm.) in which was placed sulfuric acid of the proper specific gravity to give the desired relative humidity. After the specimens were died from the slabs, they were strung on wire with small pieces of rubber separating the strips to insure that the entire surface would bc exposed to the conditioned atmosphere. These specimens were suspended from well-varaffined corks inserted in the top of the conditioning cabinet so that they could be rpadily removed and the stoppm replaced without appreciably all.ering atm o s p h e r i c conditions within the chamber. T h e relative humidities were obtained by using suliuric acid of the soecific aravitics aiven in Table 11. These d u e s were-obtained from data by Wilson.8 T h e d a t i v e humidities within the conditioning cabinrts were checked at each of the chose" temneraturrs bv means of wet and dry bulb thermometer:i inserted wiihin the conhitiming boxes and fo&d to correspond with the theoretical relative humidities within *3 per cent. These data are given in Table I11 along ~~~
Table 111-Aumiditu
~~
n e t e r m i n e t i o n e In Condittonine
Vol. 20, No. 11
with the absolute humidity expressed in grains of water per pound of dry air. T h e relative humidity obtained at 5" C. (with the lowest humidity) was omittpd in this table, since the low temperature caused erratic readings of the wet bulb thermometer. The temperature of the testing room was regulated by a thermostat and was maintained at each of the five temperatures to within *I 'F. (0.55' C.) until all of the tests at each temperature were completed.
Photoaraph Z.-Condilioninfi Cabinef Showing Suspended specimens
Stress-strain curves and tensiles were obtained with the latest autographic Scott testing machine, which was loaned to the committee by the Henry L Scott Company. This machine was set u p in the constant-temperature room 90 that the specimens were tested at the temperature at which they were conditioned. No attempt was made to regulate the relative humidity of the testing room, but the specimens were tested as soon as removed from the cabinets, and the assumution made that their adsorbed.water content would not change appreciably during the actual testing. This assumption is correct in the light of subsequcnt exprriments In the determination of stress-strain relations the averam values of four tcst specimens were taken. In some instancis where tensiles at break varied comidcrably, the average of the maximum and those that came within 5 Der cent of this maximum were taken, lower values being discariied. IJndcsirable var& tions are evident in the results, especially with respect to final tensiles, but a sufficient number ai tests wcrc made to render a v e r a g e significant. thus allowing conclusions to be drawn as to gencrd effectsof relative humidity and temperature.
Beres
Photograph 3-Lame Cabinet Comainin* P O Y ~ Humidity Chambers
INDUSTRIAL AND ENGINEERING CHEMISTRY
November, 1928
1251 I
EFFECT OF RELATIVE HUMIDITY AFTER VULCANIZATION CONDITIONED A N D T E S T E D A T 5 ° C .
C H A R TI I
RESULTS-chart 2 shows the changes in the stress-strain curves of the five compounds due to differences in cure T h e s e curves were drawn f r o m I N I T I A L TEMP 2 2 ' C . data obtained under the A - T E S T E D AT l o o t . s a m e conditions of tem45°C. perature and relative humidity and show that the s t a t e of cure affects the s t r e s s-strain relation of e a c h compound in practically the same way. Accordingly, in showing the effect of humidity and temperature the averages of the three middle cures are used in order to make the data more representa'ive as to the general trend of the effects of the variables. C h a r t 3 ( T a b l e TV) shows the effect of temperature upon the stresss t r a i n curves of the five compounds. Since i t is sometimes more convenient to note the changes in tensiles and moduli by olottinz them directlv instead d plotting the entire stress-strain curves, Chart 4 was prepared. This is merely anothrr way of presenting the same data. Chart 5 (Table V) shows the changes in the stress-strain curves of the five compounds due to variations in the relative humidity. Chart 6 gives the same information by plotting the tensiles and moduli against the relative humidity. CORRELATION OF RESULTS-In an effort to correlate as far as possible all the data obtained during this phase of the inveitigation and to show graphically the effects of relative humidity and temperature, individually or together. Charts 7 to 10 and Tables VI to IX have been prepared. Since compounds 1, 2, and 3 are gum stocks and somewhat similar in their stress strain relations. averages of the final tensiles and moduli of these three stocks were prepared. In a like manner compounds 4 and 5 were grouped, since they are both high-black tread stocks.
EFFECT OF TEMPERATURE DURING TEST
1
EQUILIBRIUM OF RAW STOCK WITH 0%AND 100%REL. HUM.
~
1 1
It
O V E R C O N C H 7 S C n AND W A T E R
I
2
3
4
5 6 7 8 DAYS E X P O S U R E
Y
IO
II
1 2 1 3
C H A R T 13
Correlation of temperature effects is shown in Chart 7 (Table VI). Corrrlation of the effects of relative humidity is given in Chart 8 (Table VII). The correlation of both temperature and relative humidity effects upon the two groups of compounds is given with Chart 9 (Tables VI11 and 1X). In this chart are plotted the final tensiles of each group a t each temperature and a single significant modulus a t each temperature. The final correlation of the effects of both temperature and relative humidity is given in Chart 10 (Table X). This chart represents the average of the five compounds and may be considered as representing in general the effect of relative humidity and temperature upon the five compounds studied. I t is possible that other compounds might be affected in other ways or to a greater or lesser extent than these averages show. The results shown so far all refer to a 2-day exposure period. Tests were made upon the middle cure of each compound after &day exposures to 0, 60, and 100 per cent relative humidities a t each of the given temperatures. Chart 11 shows compariqons between the results of 2- and 6-day exposures of compounds 3 and 4 a t corresponding cures, temperatures, and relative humidities. These charts are presented as being representative of the differ-
INDUSTRIAL AND ENGINEERING CHEMISTRY
1252
lble IV-Effect
FOR-
Hu-
MULA TEMP' MIDITI
O
1
c. 5
15
% 0 20 40 60 80 100 Av. 0 20 40 60 80 100
Av. 25
35
45
2
6
15
25
0 20 40 60 80 100 Av. 0 20 40 60 80 100 Av. 0 20 40 60 80 100 Av.
0 20 40 60 80 100 Av. 0 20 40 60 80 100 Av. 0 20 40 60 80
100 Av. 35
45
3
0 20 40 60 80 100 Av. 0 20 40 60 80 100 Av.
5
0 20 40 60 80 100 Av.
l5
2: 40 60 80 100 Av. 0 20 40 60 80 100 Av. 0 20
25
35
40
60 80
100 Av.
FINAL TENSILE
of Temperature: Average of Three Middle Cures TENSILE AT ELONGATION OF:
200%
300%
400%
500%
Lbs./ in.2 240 230 220 240 180 220 220 250 260 260 250 240 250 240 250 260 240 240 210 215 235 220 220 230 250 210 210 220 240 240 210 230 210 240 230
:;:c
Lbsi/
16 9 16 2 15 5 16 9 12 7 15 5 15 5 17 6 18 3 18 3 17 6 16 9 15 5 16 9 17 6 18 3 16 9 16 9 14 8 15 1 16 5 15 5 15 5 16 2 17 6 14 8 14 8 15 5 16 9 16 9 14 8 16 2 14 8 16 9 16 2
470 520 500 475 430 435 470 480 500 510 470 450 400 470 490 460 430 420 390 400 430 450 450 430 410 360 360 410 460 430 430 420 390 380 415
cm 33 0 36 6 35 2 33 4 30 2 30 6 33 0 33 7 35 2 35 9 33 0 31 6 28 1 33 0 34 5 32 3 30 2 29 5 27 4 28 1 30 2 31 6 31 6 30 2 28 8 25 3 25 3 28 8 32 3 30 2 30 2 29 5 27 4 26 7 29 2
253 1 231 6 231 3 210.2 229 5 230 9 231 3 242.0 232 0 227.6 219.3 229 9 297.8 229.9 234.8 228.5 239.7 225.7 241.1 231.3 232 0 233.4 221.5 297.1 215.8 227 1 224.3 225.0 236 2 217 2 210 5 210 2 213 0 214.4 217 2
270 270 245 250 220 270 255 280 270 280 290 240 260 270 250 250 270 260 240 200 245 240 260 250 260 220 230 250 250 260 230 240 210 260 250
19 0 19 0 17 2 17 6 15 5 19 0 17 9 19 7 19 0 19 7 20 4 16 9 18 3 19 0 17 6 17 6 19.0 18.3 16.9 14.1 17.2 16 9 17 6 17 6 18 3 I5 5 16 2 17 6 17 6 18 3 16 2 16 9 16 9 18 3 17 6
600 610 5130 530 560 530 565 560 530 560 530 490 460 520 480 470 470 450 430 380 450 460 450 460 450 400 390 425 450 460 450 430 400 390 430
42 2 42 9 39 4 37.3 39 4 37 3 39.7 39.4 37 3 39 4 37 3 34 4 32 3 36 6 33 7 33 0 33 0 31 6 30 2 26 7 31 6 32 3 31 6 32 3 31 6 28 1 27 4 29 9 31 6 32 3 31 6 30 2 28 1 27 4 30 2
254 8 257 5 251 3 236 9 240 1 293 9 243 9 248 2 244 6 229 2 235 5 229 2 215 1 233 4 223.6 237.6 228 -5 220.2 232 0 215 8 225.7 241.1 236.9 239.0 234 1 230.6 225 0 234.1
105 120 100 140 105 140 120 160 200 190 180 130 170 170 140 160 160 160 170 120 150 140 110 140 130 140 130 130
7 4 8 4 7 0 9 8 7 4 9 8 8 4 11 2 14 1 13 4 12 7 9 1 12 0 12 0 9.8 11.2 11.2 11.2 12.0 8.4 10.5 9.8 7.7 9.8 9.1 9.8 9.1 9.1
305 320 285 300 285 300 300 325 340 310 300 280 300 310 260 280 280 280 260 230 270 270 260 250 230 217 230 240
21.4 22.5 20 0 21 1 20 0 21.1 21.1 22.8 23 9 21.8 21.1 19.7 21 1 21.8 18.3 19.7 19.7 19.7 18.3 16.2 19.0 19.0. 18.3 17.6 16.2 15.3 16.2 16.9
(
Lbs./ in.2 3573 3620 3500 3500 3300 3390 3480 3540 3270 3370 3300 3490 3400 3395 3310 3330 3440 3530 3270 3460 3390 3470 3230 3240 3350 3243 3170 3280 3320 3140 3126 3026 3080 3120 3135
cm. 251 2 254 5 246 1 246 1 232 0 238 3 244 6 248 9 229 9 236 9 232 0 245 3 239 0 238 7 232 7 234 1 241 8 248 2 229 9 243 2 238 3 243 9 227 1 227 8 235 5 228 0 222 9 230 6 233 4 220 7 219 8 212 7 216 5 219 3 220 4
3660 3295 3290 2990 3265 3285 3290 3443 3300 3237 3120 3270 3240 3270 3340 3250 3310 3210 3430 3290 3300 3320 3150 3230 3070 3230 3190 3200 3360 3090 2995 2990 3030 3050 3090 3625 3663 3575 3370 3415 3185 3470 3530 3480 3260 3350 3260 3060 3320 3180 3380 3250 3133 3300 3070 3210 3430 3370 3400 3330 3280 3200 3330
Kg
Vol. 20, No. 11
Lbs./ in.2
Kg./ cm.
tn.
(Continued o n next page)
Kg.(
700%
:;c
@si/
87 94 87 83 81 79 85 82 78 81 73 73 63 75 73 67 61 61 59 61 64 64 64 59 60 50 49 58 61 56 55 53 49 45 63
2 2 0 0 6 9 4 0 0 3 6 3 5 2 8 5 9 9 1 2 0 0 0 8 5 6 2 0 2 2 5 4 2 7 4
2980 2860 2670 2630 2500 2540 2700 2400 2410 2640 2230 2230 2050 2330 2180 2050 1890 1980 1850 1950 1980 1900 1910 1860 1870 1570 1660 1790 1840 i6no 1640 1620 1440 1370 1585
209 5 201 1 187 7 184 9 175 8 178 6 189 8 168 7 169 4 185 6 156 8 156 8 144 1 163 8 153 3 144 1 132 9 139 2 130 1 137 1 139 2 133 6 134 3 130 8 131 5 110 4 116 7 125 8 129 4 112 5 115 3 113 9 101 2 96 3 111 4
1370 1397 1300 1200 1330 1230 1310 1220 1170 1240 1140 1065 940 1130 1040 990 950 970 860 830 940 870 900 880 860 760 710 830 870 850 780 790 700 6.iO 770
96 3 98 2 91 4 84 4 93.5 86.5 92.1 85 8 82.3 87 2 80.1 74.9 66 1 79.4 73 1 69 6 66 8 68 2 60 5 58 3 66 1 61 2 63 3 61 9 60 5 53 4 49 9 58 3 61.2 59.8 54.8 55.5 49 2 45 7 54 1
2710
190.5
2630 2670 2480 2420 2500 2290 2200 2110 2330 2050 1980 1930 1950 1830 1860 1930 1880 1870 1860 1850 1740 1650 1810 1710 1710 1640 1610 1400 1370 1590
184.9 187.7 174.3 170.1 175.8 161 0 154.7 148 3 163.8 144.1 139.2 135.7 137 1 128 6 130 8 135.7 132.2 131.5 130.8 130.1 122.3 116.0 127.2 120 2 120 2 115 3 113 2 98 4 96 3 111 8
735 800 715 700 710 620 710 690 660 610 610 560 560 615 520 530 530 510 480 430 500 490 470 470 420 400 370 440
51.7 56.2 50.3 49.2 49 9 43 6 49.9 48.5 46.4 42.9 42.9 39.4 39.4 43.2 36.6 37.3 37.3 35.9 33.7 30.2 35.2 34.4 33 0 33.0 29.5 28.1 26.0 30.9
1600 1820 1575 1600 1665 1510 1630 1450 1450 1440 1330 1260 1230 1360 1140 1110 1060 1080 1010 970 1060 1040 990 1000 930 860 810 940
112.5 127.9 110 7 112 5 117 0 106 2 114.6 101.9 101 9 101 2 93 5 88 6 86 5 95.6 80.1 78 0 74.5 75.9 71.0 68.2 74.5 73.1 69.6 70.3 65.4 60.5 56.9 66.1
Lbs./ in.2 1240 1340 1237 1180 1160 1137 1215 1167 1110 1157 1047 1043 903 1070 1050 960 880 880 840 870 910 910 910 850 860 720 700 825 870 800 790 760 700 650 760
m.
&?
cm
[
Lbs./ in.p
Kg./
2940 3285 2980 2900 3020 2810 2990 2670 2630 2660 2530 2380 2327 2530 2170 2150 2050 2160 2020 1960 2085 2050 1920 1910 1850 1780 1730 1870
206.7 230.9 209.5 203.9 212.3 197.5 210.2 187.7 184.9 187.0 177.9 167.3 163.6 177.9 152.6 151.1 144.1 151.8 142.0 137.8 146.6 144.1 135.0 134.3 130.1 125.1 121.6 131.5
cm.2
INDUSTRIAL A X D ENGINEERISG CHEMIIXTR Y
November. 1928
of T e m p e r a t u r e :
T a b l e IV-Effect
FOR-
OC.
3
15
3430 3320 3310 3320 3220 3250 3310
240 4 233 4 232 7 233 4 226 4 228 5 232 7
4325 4530 4495 4415 4425 4450 4440 4290 4190 4370 4300 4270 4350 4295 4170 4190 4030 4230 4180 4220 4170 3860 3790 3830 3880 3870 3920 3860 3537 3520 3450 3670 3490 3490 3530
304 0 318 5 316 0 310 4 311 1 312 8 312 1 301 6 294 6 307 2 302 3 300 2 305 8 301 9 293 2 294 6 283 3 297 4 243 9 296 7 293 2 271 4 266 4 269 2 272 8 272 1 275 6 271 4 248 7 247 5 242 5 258 0 245 3 245 3 248 2
4760 4757 4730 4660 4850 4710 4740 4513 4500 4560 4580 4610 4480 4540 4340 4460 44CO 4380 4260 4420 4375 4340 4153 4230 4200 4190 4180 4220 4160 4140 4050 4060 3950 4020 4060
333.9 334.4 332 5 327.6 341.0 331.1 333.2 317.3 316.4 320.6 322.0 324.1 314.9 319.2 305.1 313.5 309.3 307.9 299.5 310.7 307.6 305.1 292.0 297.4 295.3 294.6 293.9 296.7 292.4 291.0 284.7 285.4 277.7 282.6 285.4
0
20 40 60 80
0
20 40 60 80
100
15
Av. 0
20 40 60 80
100 Av. 25
35
45
0
20 40 60 80 100 AY. 0
20 40 60 80 100 Av. 0
20 40 60 80 100 Av.
5
5
15
0 20 40 60 80 100 Av. 0
20 40 60 80
100 25
Av. 0
20 40 60
80 100 Av.
35
0
20 40 60 80
100 45
Av. 0
20 40 60
80 100 Av.
500%
300%
70
100 5
TENSILE AT ELOXGATION OF:
TENSILE
Av.
4
Average of T h r e e M i d d l e Cures-(Continued)
FINAL
HU-
MULA TEMP' X I D I T Y
Lbs./ in.=
K2.4 cm.
150 140 120 120 140 120 130
10 5 98 8 4 84 98 8 4 9.1
280 270 230 270 240 230 250
19 7 19 0 16 2 19 0 16 9 16 2 17 6
470 470 430 450 390 360 430
730 760 720 710 720 650 715 730 700 700 680 670 650 690 710 680 660 680 630 610 660
59 8 63 3 59 8 56 9 61 9 56 2 59 8 56 2 54 1 57 6 55 5 56 2 58 3 56 2 51 3 53 4 50 6 49 9 50 6 45 7 50 3 51 3 49 2 44 2 47 8 47 1 45 7 48 5 49 9 47 8 46 4 47 8 44 3 42 9 46 4
1680 1720 1650 1625 1690 1580 1660 1520 1500 1590 1520 1510 1550 1530 1380 1380 1370 1340 1340 1260 1345 1310 1290 1280 1260 1240 1210 1265 1270 1200 1190 1220 1140 1130 1190
118 1 120 9 116 0 114 2 118 8 111 1 116 7 106 9 105 5 111 8 106 9 in6 2 109 0 107 6 97 0 97 0 96 3 94 2 94 2 88 6 94 6 92 1 90 7 90 0
2670 2750 2710 2680 2720 2507 2670 2390 2413 2503 2367 2370 2390 2410 2180 2210 2130 2150 2150 2070 2150 2030 2030 1980 1970 1870 1900 1980 1940 1880 1810 1850 1740 1780 1830
187 7 193 3 190 5 188 4 191 2 176 2 187 7 168 0 169 6 176 0 166 4 166 6 168 0 169 4 153 3 155 4 149 7 151 1 151 1 145 5 151 1 142 7 142 7 139 2 138 5 138 5 133 0 139 2 136 4 132 2 127 2 130 1 122 3 125 1 128 6
3740 3815 3770 3750 3840 3600 3760 3435 3470 3560 3400 3435 3490 3465 3160 3150 3n70 3130 3130 3080 3120 2890 2910 2860 2840 2840 2780 2850 2770 2680 2620 2650 2520 2530 2630
262 270 265 263 270 253 264 241 243 250 239 241 245 243 222 221 215
670 680 650 665 670 675 670 670 610 660 640 640 630 640 590 610 570 540 510 530 560 510 470 550 470 490 480 500 500 510 500 480 460 440 480
47 1 47 8 45 7 46 7 47 1 47 5 47 1 47 1 42 9 46 4 45 0 45 0 44 3 45 0 41 5 42 9 40 1 38 0 35 9 37 3 39 4 35 9 33 0 38 7 33 0 34 4 33 7 35 2 35 2 35 9 35 2 33 7 32 3 30 9 33 7
1460 1460 14-50 1435 1460 1450 1450 1340 1250 1350 1300 1320 1250 1300 1220 1220 1100 1160 1100 1120 1150 1040 1030 1100 1020 1030 1000 1040 1040 1030 1020 980 950 910 990
102.6 102.6 101.9 100.9 102.6 101.9 101.9 94.2 87.9 94.9 91.4 92.8 87.9 91.4 85.8 85.8 77.3 81.5 77.3 78.7
2450 2500 2475 2400 2470 2390 2450 2230 2130 2230 2150 2180 2130 2175 2000 1990 1950 1980 1890 1870 1950 1740 1710 1830 1710 1740 1690 1740 1720 1710 1660 1630 1600 1520 1640
172 2 175.8 174 0 168 7 173 6 168 0 172.2 156 8 149 7 156 8 151 1 153 3 149 7 152 9 140 6 139 9 137 1 139 2 132 9 131 5 137.1 122.3 120.2 128.6 120.2 122.3 118.8 122.3 120.9 120.2 116.7 114.6 112.5 106.9 115.3
3590 3630 3620 3495 3638 3490 3740 3230 3160 3590 3210 3210 3150 3260 2960 2920 2870 3010 2870 2830 2910 2610 2570 2730 2570 2610 2550 2610 2570 2550
262.4 255 2 254.5 245 7 255 8 245 3 262.9 227.1 222.1 252.4 225.7 225.7 221.4 229.2 208.1 205.3 201.8 211.6 201.8 198.9 204.6 183.5 180.7 191.9 180.7 183.5 179.3 183.5 180.7 179.3 169,4 168.7 165 9 161.0 170.8
850 900 850 810 880 800 850 800
770 820 790 800
830 800
88 6
87 2 85 1 88 9 89 3 84 4 83 7 85 8 80 1 79 4 83 7
80.8
73.1 72.4 77.3 71.7 72.4 70.3 73.1 73.1 72.4 71.7 68.9 66.8 64.0 69.6
ences shown by all the stocks as the result of the difference in length of exposure. In order to show the effect of temperature only during the time of actual testing, specimens of the first compound, cured 60 minutes a t 287'F. (141.7" C.), were allowed to come to a temperature of 71.6' F. (22' C.). The temperature of the testing room was held a t 50" F. (10' C.), and while a t this temperature the specimens were brought singly into the room, placed in the testing machine, and tested. This procedure was repeated while the temperature of the testing room was maintained a t 113" F.
-.,.
fd.5' P \*"
Thtvc
the
1253
cnet-imenc hnrl...AtL h e E nme .,yc-'.Yc'~.,"."u .,YAY.
initin1 tmmnemtqrve I1.11IU. LC.A.yC'ULY.-.
I t is a well-known fact that heat is generated within the specimen itself during the test. In the case of the high-temperature testing this heat may be retained in the specimen, but in the case of the low-temperature testing this heat would be partially dissi-
bz:2360 ?lo" 2290 2430
33 0 33 0 30 2 31 6 27 4 25 3 30 2
980 930 870 900 780 760 870
68.9 65.4 61.2 63 3 54.8 53.4 61.2
1940 1780 1690 1803 1610 1550 1730
136.4 125.1 118.8 126.8 113.2 109.0 121.6
I
9 3 0
6 0
1 3 5
9 3 0
5 3 6 1 4 8
zzn o
220 0 216 5 219 3 203 2 204 6 201 1 199 7 199 7 195 4 200 4 194 7 188 4 184 2 186 3 177 2 177 9 184 9
4530
318.5
4260 4180 4250 4230 4270 4180 4230
299.5 293.9 298.8 297.4 300 2 293.9 297.4
3900
274.2
3660 3560 3750 3620 3590
257.3 250.3 263 6 254.5 252.4
3550 3620 3560 3460 3350 3400 3320 3230 3390
249 6 254.5 250.3 243.2 235.5 239.0 233.4 227.1 238.3
iated.0 Chart 12 shows the variation of this stock under the .wo conditions. Coh.cLusxoNs-Within the ranges of relative humidity and temperature studied in this investigation. the effect of temperature is approximately three times as great as the effect of the relative humidity changes. The sensitivity of specimens is illustrated by the fact that an increase of 18' F. (10"C.) is sufficient to cause a decreaw in final tensile and modulus corresponding to a 25 to 40 per cent decrease in time of cure. An increase of 20 points in relative humidity is equivalent to a decrease in time of , . . . r o C U
nf frnm 9 eL "n" F. -0.. l l " l y Y YC'
I C V L
,.an+ CCII,,.
A study of the data shows that it is necessary to control the
-
Boone and Newman, IND.ENQ.CHBM.,18, 539 (1926).
1254
INDUSTRIAL AND ENGINEERING CHEMISTRY Table V-Effect
FOR- HuMULA MIDITY
1
%
c.
0
5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av.
20
40
60
80
100
2
0
20
40
60
80
100
3
TBM
0
20
40
60
FINAL TENSILE Kg./
of Humidity: Averarle of Three Middle Cures TENSILE AT ELONGATION OF: ~
200%
240 250 250 220 240 240 230 260 260 220 240 240 220 260 240 230 210 230 240 230 240 230 230 230 180 240 210 210 210 225 220 220 215 210 240 220
Kg.i/ cm. 16.9 17.6 17.6 15.5 16.9 16.9 16.2 18.3 18.3 15.5 16.9 16.9 15.5 18.3 16.9 16.2 14.8 16.2 16.9 16.2 16.9 16.2 16.2 16.2 12.7 16.9 14.8 14.8 14.8 15.8 15.5 15.5 15.1 14.8 16.9 15.5
Lbs.! tn. 470 480 490 450 460 470 520 500 460 450 430 470 500 510 430 430 430 460 475 470 420 410 420 440 430 450 390 360 390 400 435 400 400 360 380 390
253.1 242.0 234.8 233.4 236.2 239.7 231 6 232.0 228.5 221.4 217.2 226.4 231.3 227.8 232.7 227.1 210.5 225.7 210.2 219.3 225.7 215.8 210.2 216.5 229.5 229.9 241.1 227.1 213.0 227.8 230.9 227.8 231.3 224.3 214.4 225.7
270 280 250 240 250 260 270 270 250 250 260 260 245 280 270 250 230 255 250 290 260 260 240 260 220 240 240 220 240 230 270 260 200 230 260 240
19.0 19.7 17.6 16 9 17 6 18.3 19.0 19.0 17.6 17.6 18.3 18.3 17.2 19.7 19.0 17.6 16.2 17.9 17.6 20.4 18.3 18 3 16.9 18.3 15.5 16.9 16.9 15.5 16.9 16.2 19.0 18.3 14.1 16.2 18 3 16.9
600 560 480 460 450 510 610 530 470 450 460 500 560 560 470 460 450 500 530 530 450 450 430 480 560 490 430 400 400 460 530 460 380 390 390 430
254.8 248.2 223.6 241.1 240.4 241.8 257.5 244.6 237.6 236.9 233.4 241.8 251.3 229.2 228.5 239.0 232.7 236.2 236.9 235.5 220.2 234.1 233.4 232.0
105 160 140 140 150 140 120 200 160 110 140 140 100 190 160 140 120 140 140 180 160 130 120 140
7.4 11.2 9.8 9.8 10.5 9.8 8.4 14.1 11.2 7.7 9.8 9-8 7.0 13.4 11.2 9.8 8.4 9.8 9.8 12.7 11.2 9.1 8.4 9.8
305 325 260 270 280 290 320 340 280 260 270 290 285 310 280 250 230 270 300 300 280 230 270 270
LPs.4 an.
3570 3540 3310 3470 3320 3440 3620 3270 3330 3230 3140 3320 3500 3370 3440 3240 3126 3330 3500 3300 3530 3350 3026 3370 3300 3490 3270 3243 3080 3280 3390 3403 3460 3170 3120 3310
251.0 248.9 232.7 243.9 233.4 241.8 254.5 229.9 234.1 227.1 220.7 233.4 246.1 236.9 241.8 227.8 219.8 234.1 246.1 232.0 248.2 235.5 212.7 236.9 232.0 245.3 229.9 228.0 216.5 230.6 238.3 239.2 243.2 222.9 219.3 232.7
5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av.
3600 3443 3340 3320 3360 3410 3295 3300 3250 3150 3090 3220 3290 3240 3310 3230 2995 3210 2990 3120 3210 3070 2990 3080 3265 3270 3430 3230 3030 3240 3285 3240 3290 3190 3050 3210
5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av.
3625 8530 3180 3430 3420 3440 3663 3480 3380 3370 3320 3440 3575 3260 3250 3400 3310 3360 3370 3350 3133 3330 3320 3300
(n.
400%
300%
Cm.
LPS.2/
Vol. 20, No. 11
(Continued on next page)
Kg.4
500% Lbs./
1240 1167 1050 910 870 1050 1340 1110 960 916 800 1025 1237 1157 880 853 790 980 1180 1047 880 857 760 945 1160 1043 840 720 700 890 1137 903 870 700 650 850
Kg.; cm. 87.2 82.0 73.8 64.0 61.2 73.8 94.2 78.0 67.5 64.4 56.2 72.1 87.0 81.3 61.9 60.0 55.5 68.9 83.0 73.6 61.9 60.2 53.4 66.4 81.5 73.3 59 1 50.6 49.2 62.6 79.9 63.5 61.2 49.2 45.7 59.8
42.2 39.4 33.7 32.3 31.6 35.9 42.9 37.3 33.0 31.6 32.3 35.2 39.4 39.4 33.0 32.3 31.6 35.2 37.3 37.3 31.6 31.6 30.2 33.7 39.4 34.4 30.2 28.1 28.1 32.3 37.3 32.3 26.7 27.4 27.4 30.2
1370 1223 1040 870 870 1070 1397 1170 990 900 850 1060 1300 1240 950 880 780 1030 1200 1140 970 860 790 990 1330 1065 860 760 700 940 1225 940 830 710 650 870
96.3 86.0 73.1 61.2 61.2 75.2 98.2 82.3 69.6 63.3 59.8 74.5 91.4 87.2 66.8 61.9 54.8 72.4 84.4 80.1 68.2 60.5 55.5 69.6 93.5 74.9 60.5 53.4 49.2 66.1 86.1 66 1 58.3 49 9 45.7 61.2
21.4 22.8 18.3 19.0 19.7 20.4 22.5 23.9 19.7 18.3 19.0 20.4 20.0 21.8 19.7 17.6 16.2 19.0 21.1 21.1 19.7 16.2 19.0 19.0
735 690 520 490 470 580 800 660 530 470 470 580 715 610 530 470 430 550 700 610 510 420 450 540
51.7 48.5 36.6 34.4 33.0 40.8 56.2 46.4 37.3 33.0 33.0 40.8 50.3 42.9 37.3 33.0 30.2 38.7 49.2 42.9 35.9 29.5 31.6 38.0
cm. 33.0 33.7 34.4 31.6 32.3 33.0 36.6 35.2 32.3 31.6 30.2 33.0 35.2 35.9 30.2 30.2 30.2 32.3 33.4 33.0 29.5 28.8 29.5 30.9 30.2 31.6 27 4 25.3 27.4 28.1 30.6 28.1 28.1 25.3 26.7 27.4
in.2
.??si/
Kg../,
2980 2400 2180 1900 1840 2260 2860 2410 2050 1910 1600 2170 2670 2640 1890 1860 1640 2140 2630 2230 1980 1870 1620 2070 2500 2230 1850 1570 1440 1920 2540 2050 1950 1660 1370 1870
cm. 209.5 168.7 153.3 133.6 129.4 158.9 201.1 169.4 144.1 134.3 112.5 152.6 187.7 185.6 132.9 130.8 115.3 150.4 184.9 156.8 139.2 131.5 113.9 145.5 175.8 156.8 130.1 110.4 101.2 135.0 178.6 144.1 137.1 116.7 96.3 131.5
2710 2480 2050 1880 1710 2170
190,5 174.3 144.1 132.2 120.2 152.6
2420 1980 1870 1710 2140
170.1 139.2 131.5 120.2 150.4
2500 1930 1860 1640 2110
175.8 135.7 130.8 115.3 148.3
2290 1950 1850
161.0 137.1 130.1
2030 2670 2200 1830 1740 1400 1990 2630 2110 1860 1650 1370 1920
142.7 187.7 154.7 128.6 122.3 98.4 139.9 184.9 148.3 130.8 116.0 96.3 135.0
1600 1450 1140 1040 980 1240 1820 1450 1110 990 930 1260 1575 1440 1060 1000 870 1190 1600 1330 1080 930 900 1170
112.5 101.9 80.1 73.1 68.9 87.2 127.9 101.9 78.0 69.6 65.4 88.6 110.7 101.2 74.5 70.3 61.2 83.7 112.5 93.5 75.9 65.4 63.3 82.3
m.
Lbs./ in.2
Kg; cm.
2940 2670 2170 2050 1940 2390 3285 2630 2150 1920 1780 2390 2980 2660 2050 1910 1690 2260 2900 2530 2160 1850 1803 2250
206.7 187.7 152.6 144.1 136.4 168.0 230.9 184.9 151.1 135.0 125.1 168.0 209.5 187.0 144.1 134.3 118.8 158.9 203.9 177.9 151.8 130.1 ,126.8 158.2
INDUSTRIAL A N D EA-GII1;EERILVGCHEJUSTRY
November, 1928
Table V-Effect
FOR- HuMULA IZIDITY TEMP'
3
of Humidity: Average of Three Middle'Cures-(Confinued) TENSILE AT
FINAL TENSILE
300%
70
oc.
80
5 15 25 35 45 Av. 5 15 25 35 45 Av.
Lbs./ in.= 3415 3260 3300 3280 3220 3295 3185 3060 3070 3200 3250 3153
cm. 240.1 229.2 232.0 230.6 226.4 231.6 223 9 215 1 215 8 225 0 228.5 221.7
5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av.
4325 4290 4170 3860 3537 4040 4530 4190 4190 3790 3520 4040 4495 4370 4030 3830 3450 4035 4415 4300 4230 3880 3670 4100 4425 4270 4180 3870 3490 4050 4450 4350 4220 3920 3490 4090
304.0 301 6 293.2 271.4 248.7 284.0 318.5 294.6 294.6 266.4 247.5 284.0 316.0 307.2' 283.3 269.2 242.5 283.7 310.4 302.3 297.4 272.8 258.0 288.2 311.1 30Q.2 293.9 272.1 245.3 284.7 312.8 305.8 296,7 275.6 245.3 287.5
850 800 730 730 710 760 900 770 760 700 680 760 850 820 720 700 660 750 810 790 710 680 680 735 880 800 720 670 630 740 800 830 650 650 610 710
59 56 51 51 49 53 63 54 53 49 47 53 59 57 50 49 46 52 56 55 49 47 47 51 61 56 50 47 44 52 56 58 45 45 42 49
5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 5 15 25 35 45 Av. 0 5 15 25 35 45
4750 4513 4340 4340 4160 4420 4760 4500 4460 4153 4140 4400 4730 4560 4400 4230 4050 4390 4660 4580 4380 4200 4060 4380 4850 4610 4260 4190 3950 4370 4710 4480 4420 4180 4020 4360
333.9 317.3 305.1 305.1 292.4 310.7 334.6 316.4 313.5 292.0 291.0 309.3 332.5 320.6 309.3 297.4 284.7 308.6 327.6 322.0 307.9 295.3 285.4 307.9 341.0 324.1 299.5 294.6 277.7 307.2 331.1 314.9 310.7 293.9 282.6 306.5
670 670 590 510 500 590 680 610 610 470 510 580 650 660 570 .. 550 500 580 665 640 540 470 480 560 670 640 510 490 460 550 675 630 530 480 440 550
100
4
0
"0
40
60
80
100
5
0
20
40
~~
60
8
AV.
100
5 15 25 35 45 Av.
Kg.;
Lbs./ in.=
~
1255
Kg./
Lbs./
Kg.;
.OXGATION O F :
500%
400%
600%
cm. 7.4 9.1 12.0 9.8 9.8 9.8 9.8 12.0 8.4 9.1 8 4 9.8
Lbs./ in.= 285 280 260 217 240 2fi0 300 300 230 230 230 260
Kg.(
cm. 20.0 19.7 18.3 15.3 16.9 18.3 21.1 21.1 16.2 16.2 16.2 18.3
710 560 480 400 390 510 620 560 430 370 360 470
49.9 39.4 33.7 28.1 27.4 35.9 43.6 39 4 30.2 26.0 25 3 33.0
8 6 6 2 4 7 9 5 9 8 8 7 9 2 6 1 3 0 2 3 7 7 9 9
1680 1520 1380 1310 1270 1430 1720 1500 1380 1290 1200 1420 1650 1590 1370 1280 1190 1420 1625 1520 1340 1260 1220 1390 1690 1510 1340 1240 1140 1380 1580 1550 1260 1210 1130 1350
118.1 106.9 97 0 92.1 89.3 100.5 120.9 105.5 97.0 90.7 84.4 99.8 116.0 111.8 96.3 90.0 83.7 99.8 114.2 106.9 94.2 88.6 85 8 97.7 118.8 106.2 94.2 87.2 80.1 97.0 111.1 109.0 88.6 85.1 79.4 94.9
2670 2390 2180 2030 1940 2240 2750 2413 2210 2030 1880 2260 2710 2503 2130 1980 1810 2230 2680 2367 2150 1970 1850 2200 2720 2370 2150 1970 1740 2190 2507 2390 2070 1900 1780 2130
187.7 168.0 153.3 142.7 136.4 157 5 193 3 169 6 155 4 142 7 132 2 158 9 190 5 176 0 149 7 139 2 127 2 156 8 188.4 166.4 151.1 138.5 130.1 154.7 191.2 166.6 151.1 138.5 122.3 154.0 176.2 168.0 145.5 133.6 125.1 149.7
3740 3435 3160 2890 2770 3200 3845 3470 3150 2910 2680 3210 3770 3560 3070 2860 2620 3180 3750 3400 3130 2840 2650 3150 3840 3435 3130 2840 2520 3150 3600 3490 3080 2780 2530 3100
262.9 241 5 222 1 203 2 194 7 225.0 270.3 243.9 221.4 204 6 188 4 225 7 265.0 250.3 215.8 201.1 184.2 223.6 263.6 239.0 220.0 199.7 186.3 221.4 270.0 241.5 220.0 199.7 177.2 221.4 253.1 245.3 216.5 195.4 177.9 217.9
47.1 47.1 41.5 35.9 35.2 41.5 47.8 42.9 42.9 33.0 35.9 40.8 45.7 46.4 40.1 38.7 35.2 40.8 46.7 45.0 38.0 33.0 33.7 39.4 47.1 45.0 35.9 34.4 32.3 38.7 47.5 44.3 37.3 33.7 30.9 38.7
1460 1340 1220 1040 1040 1220 1460 1250 1220 1030 1030 1200 1450 1350 1100 1100 1020 1200 1435 1300 1160 1020 980 1180 1460 1320 1100 1030 950 1170 1450 1250 1120 1000 910 1150
102.6 94.2 85.8 73.1 73.1 85.8 102.6 87.9 85.8 72.4 72.4 84.4 101.9 94.9 77.3 77.3 71.7 84.4 100.9 91.4 81.5 71.7 68.9 83.0 102.6 92.8 77.3 72.4 66.8 82.3 101.9 87.9 78.7 70.3 64.0 80.8
2450 2230 2000 1740 1720 2030 2500 2130 1990 1710 1710 2010 2475 2230 1950 1830 1660 2030 2400 2150 1980 1710 1630 1970 2470 2180 1890 1740 1600 1970 2390 2130 1870 1690 5120 1920
172.2 156.8 140.6 122.3 120.9 142.7 175.8 149.7 139.9 120.2 120.2 141.3 174.0 156.8 137.1 128.6 116.7 142.7 168.7 151.1 139.2 120.2 114.6 138.5 173.6 153.3 132.9 122.3 112.5 138.5 168.0 149.7 131.5 118.8 106.9 135.0
3590 3230 2960 2610 2570 2990 3630 3160 2920 2570 2550 2970 3620 3590 2870 2730 2410 3040 3495 3210 3010 2570 2400 2940 3638 3210 2870 2610 2360 2930 3490 3150 2830 2550 2290 2860
252.4 227.1 208.1 183.5 180.7 210.2 255 2 222 1 205 3 180 7 179 3 208.5 254.5 252.4 201.8 191.9 169.4 213.7 245.7 226.7 211.6 180.7 168.7 206.7 255.8 225.7 201.8 183.5 165.9 206.0 245.3 221.4 198.9 179.3 161.0 201.1
cm.2
8 2 3 3 9 4
3
1 4 2 8 4
in.2 105 130 170 140 140 140 140 170 120 130 120 140
tem perature of the testing room within narrow limits in order t o secure comparable results. For practical purposes the temperature should be maintained within +2O F. (1.l'C.). The relative humidity of the testing room does not have t o be controlled if the specimens are conditioned in cabinets. While there is a slightly increased effect due to continued adsorption of moisture for the 6-day exposure, the difference is too small to warrant longer than a 2-day conditioning period. Subsequent work shows 24-hour ,exposure t o be satisfactory. At the
1665 1260 1010 860 780 1115 1510 1230 970 810 760 1060
117.0 88.6 71.0 60.5 54.8 78.4 106.2 68.5 68.2 56.9 53.4 74.5
4260
299.5
3660 3560 3860
257.3 250.3 271.4
4180 3900 3560 3460
293.9 274.2 250.3 243.2
4250
298.8
3750 3350
263.6 235.5
4230
297.4
3620 3400
254.5 239.0
4270
300.2
3590 3320
282.4 233.4
4180 3840 3550 3230
293.9 270.0 249.6 227.1
700%
Lbs.1 in.= 3020 2380 2020 1780 1610 2160 2810 2327 1960 1730 1550 2080
Ks./
cm.2 212.3 167.3 142.0 125.1 113.2 151.8 197.5 163.6 137.8 121.6 109.0 146.2
higher temperatures the 6-day exposures gave irregular results, no doubt due to aging effects. The effect of temperature upon the physical properties is practically the same for the five compounds. The physical properties of the gum stocks are affected .more than the carbon-black stocks by changes in relative humidity. The guanidine and mercaptobenzothiazole stocks showed very little difference in their sensitivity to changes in relative humidity. The softeners exerted only a negligible effect upon the results.
(Text of Part 11 folkI W S on page 1259)
INDUSTRIAL A N D ENGINEERING CHEMISTRY
1256
of TemDerature: Average of Three Middle Cures a t Six Humidities of Formulas 1, 2, a n d 3, a n d of Formulas 4 a n d 5
Table VI-Effect
; : :$
c. 5
15
25
35
45
5 15 25 35 45
200%
1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av.
Lbs./in.2 3480 3290 3470 3410 3395 3270 3320 3330 3390 3300 3210 3300 3280 3200 3330 3270 3135 3090 3310 3180
K e".,/ c m . 244.6 231.3 243.9 239.7 238.7 229.9 233.4 234.1 238.3 232.0 225.7 232.0 230.6 225.0 234.1 229.9 220.4 217.2 232.7 223.6
4 5 Av. 4 5 AV. 4 5 Av. 4 5 Av. 4 5 Av.
4440 4740 4590 4295 4540 4420 4170 4375 4280 3860 4220 4040 3530 4060 3800
312.1 333.2 322.7 301.9 319.2 310.7 293.2 307.6 300.9 271.4 296.7 284.0 248.2 285 4 267.1
Table VII-Effect
IHu- 7
FOR-
MIDITY
MULA
TENSILE AT ELONGATION OF:
FINAL TENSILE
TEMP.
LbsJin.2
850 670 760 800 640 720 715 560 640 690 500 595 660 480 570
3001,
59.8 47.1 53 4 56.2 45.0 50.6 50.3 39.4 45.0 48.5 35.2 41.8 46.4 33.7 40.1
20
40
60
80
100
0 20
60 80 100
220 225 120 190 240 270 170 230 235 245 150 210 220 250 130 200 230 250 130 200
15.5 15.8 8.4 13.4 16.9 19.0 12.0 16.2 16.5 17.2 10.5 14.8 15.5 17.6 9.1 14.1 16.2 17.6 9.1 14.1
1660 1450 1555 1530 1300 1415 1345 1150 1250 1265 1040 1150 1190 990 1090
116.7 101.9 109.3 107 6 91.4 99.5 9+.6 80.8 87.9 88.9 73.1 80.8 83.7 69.6 76.6
LbsJin.2 470 565 300 445 470 520 310 430 430 4 50 270 380 410 425 240 360 415 430 250 370
Kg./cm.Z 33.0 39.7 21.1 31.3 33 0 36 6 21.8 30.2 30 2 31 6 19.0 26.7 28 8 29.9 16.9 25.3 29.2 30.2 17.6 26.0
Lbs./in.2 1215 1310 710 1080 1070 1130 615 940 910 940 500 780 825 830 440 700 760 770 430 650
Kg./cm.z 85.4 92.1 49.9 75.9 75.2 79.4 43.2 66.1 64.0 66.1 35.2 54.8 58.0 58.3 30.9 49.2 53.4 54.1 30.2 45.7
2670 2450 2560 2410 2175 2290 2150 1950 2050 1980 1740 1860 1830 1640 1735
187.7 172.2 180.0 169 4 152.9 161.0 151.1 137.1 144.1 139.2 122.3 130.8 128.6 115.3 122.0
3760 3740 3750 3165 3260 3360 3120 2910 3015 2850 2610 2730 2630 2430 2530
264.3 262.9 263.6 243.6 229.2 236.2 219.3 204 6 212.0 200.4 183.5 191.9 184.9 170.8 177.9
2700 2670 1630 2330 2330 2330 1360 2010 1980 1930 1060 1660 1790 1810 940 1510 1585 1590 870 1350
189.8 187.7 114.6 163.8 163.8 163.8 95.6 141.3 139.2 135.7 74.5 116.7 125.8 127.2 66.1 106.2 111.4 111.8 61.2 94.9
of Humidity: Average of Three Middle Cures a t Five Temperatures of Formulas 1, 2, a n d 3, a n d Formulas 4 a n d 5 TEXSILE AT B L O N G A T I O N OF:
FINAL TENSILE
40070
300%
1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av.
3440 3410 3440 3430 3320 3220 3440 3330 3330 3210 3360 3300 3370 3080 3300 3250 3280 3240 3295 3240 3310 3210 3153 3220
241.8 239.7 241.8 241.1 233.4 226.4 241.8 234.1 234.1 225 7 236 2 232 0 236 9 216 5 232.0 228.5 230.6 227 8 231.6 227.8 232.7 225 7 221.7 226.4
4 5 Av. 4 6 Av.
4040 4420 4230 4040 4400 4220 4035 4390 4210 4100 4380 4240 4050 4370 4210 4090 4360 4225
284.0 310.7 297.4 284.0 309.3 296.7 283.7 308.6 296.0 288.2 307.9 298.1 284.7 307.2 296.0 287.5 306.5 297.0
4 5 Av. 4 5 Av. 4 5 Av.
500%
400%
Kg./cm.Z
Lbs./in.? 240 260 140 210 240 260 140 210 230 255 140 210 230 260 140 210 225 230 140 200 220 240 140 200
% 0
Vol. 20, No. 11
760 590 675 760 580 670 750 580 665 735 560 650 74C 550 640 710 550 630
53.4 41.5 47.5 53.4 40.8 47.1 52 7 40 8 46.7 51.7 39.4 48.7 52.0 38 7 45.0 49.9 38.7 44.3
1430 1220 1325 1420 1200 1310 1420 1200 1310 1390 1180 1285 1380 1170 1275 1350 1150 1250
Kg./cm.? 16 9 18 3 9 8 14 8 16 9 18 3 9 8 14 8 16 2 17 9 9 8 14 8 16 2 18 3 9 8 14 8 15 8 16 2 9 8 14 1 15.5 16.9 9.8 14.1 100 5 85 8 93.1 99.8 84.4 92.1 99.8 84.4 92.1 97.7 83.0 90.3 97.0 82.3 89.6 94.9 80.8 87.9
LbsJin.2 470 510 290 420 470 500 290 420 460 500 270 410 440 480 270 400 400 460 260 370 390 430 260 360 2240 2030 2135 2260 2010 2135 2230 2030 2130 2200 1970 2085 2190 1970 2080 2130 1920 2025
500%
K g . / c m . ? Lbs./in.Z 1080 33.0 35.9 1070 20.4 580 29.5 . 900 33.0 1025 1060 35.2 580 20.4 29.5 890 980 32 3 35 2 1030 550 19.0 28.8 850 30.9 945 990 33.7 540 19.0 28.1 820 28.1 940 32.3 510 18 3 780 26.0 850 27 4 870 30.2 18.3 470 730 25.3
"*
157 5 142 7 150 1 158 9 141 3 150.1 155 8 142 7 149 7 154 7 138 5 146 6 154 0 138 5 146 2 149 7 135 0 142.4
3200 2990 3095 3210 2970 3090 3180 3040 3110 3150 2940 3045 3150 2930 3040 3100 2860 2980
KgJcrn.2 73.8 75.2 40.8 63.3 72.1 74.5 40.8 62.6 68.9 72.4 38.7 59.8 66.4 69.6 38.0 57.6 62.6 66.1 35.9 54.8 59 8 61.2 33.0 51.3 225.0 210.2 217.6 225.7 208.8 217.2 223.6 213.7 218.6 221.4 206.7 214.1 221.4 206.0 213.7 217.9 201.1 209.5
600%
Lbs./in.' 2260 2170 1240 1890 2170 2140 1260 1860 2140 2110 1190 1810 2070 2030 1170 1760 1920 1990 1115 1676 1820 1920 1060 1600
Kg./cm.' 158.9 152.6 87.2 132.9 152.6 150.4 88.6 130.8 150.4 148.3 83.7 127.2 145.6 142.7 82.3 123 7 135 0 139 9 78 4 117.8 127.9 135 0 74 5 112.5
IA'DUSTRIAL AND ENGINEERING CHEiMISTRY
November, 1928
TEXP.
E&:;,I
OC.
70
5
0
20
40
60
80
100
15
0
20
40
60
80
100
Table VIII-Effect
of H u m i d i t y : Average of Three Middle Cures of Formulas 1, 2, a n d 3
TENSILE AT ELONGATION OF:
FINALTENSILE 300%
Lbs./in.' 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av.
3570 3600 3625 3600 3620 3295 3663 3520 3500 3290 3575 3450 3500 2990 3370 3290 3300 3265 3415 3320 3390 3285 3185 3285
1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av.
3540 3440 3530 3500 3270 3300 3480 3350 3370 3237 3260 3290 3300 3120 3350 3290 3490 3270 3260 3340 3400 3240 3060 3270
3
Kg./cm.z 251.0 253.1 254,s 253.1 254.5 231.6 257.5 247.5 246.1 231 3 251.3 242.5 246.1 210.2 236.9 231.3 232.0 229.5 240.1 233.4 238.3 230.9 223.9 230.9 248 241 248 246 229 232 244 235 236 227 229 231 232 219 235 231 245 229 229 234 239 227 215 229
9 8 2 1 9 0 6 5 9 6 2 3 0 3 5 3 3 9 2 8 0 8 1 9
60
80
100
35
1 2 3 Av. 1
2 3 Av. 1 2 3 Av. 1 2 3 Av.
3470
0
20
40
60
80
3440 3310 3250 3330 3530 3210 3133 3290
1 2 3 Av. 1 2 3 Av. 1
2 3 Av. 1
2 3 Av.
3230 3150 3370 3250 3240 3230 3400 3290 3350 3070 3330 3250 3243 3230 3280 3260
400%
600%
500%
Lbs./in.a 2980 2710 1600 2430 2860 2660 1820 2450 2070 2610 1575 2235 2630 2010 1600 2280 2500 2610 1665 2260 2540 2630 1510 2230
Kg.1crn.Z
Lbs./in.'
Kg./cm.l
Lbs./in.Z
Kg./cm.'
LbsJin.2
240 270 105 205 230 270 120 205 220 245 100 190 240 250 140 210 180 220 105 170 220 270 140 210
16.9 19 0 7.4 14.4 16 2 19 0 8.4 14.4 15.5 17 2 7 0 13.4 16 9 17 6 9 8 14 8 12 7 15 5 7 4 12 0 15 5 19 0 9 8 14.8
470 600 305 460 520 610 320 480 500 560 285 450 475 530 300 435 430 560 285 425 435 530 300 420
33.0 42 2 21.4 32.3 36 6 42 9 22 5 33 7 35 2 39 4 20 0 31 6 33 4 37 3 21 1 30 6 30 2 39 4 20 0 29 9 30 6 37 3 21 1 29 5
1240 1370 735 1115 1340 1397 800 1178 1237 1300 715 1085 1180 1200 700 1030 1160 1330 710 1060 1137 1225 620 995
Kg./cm.l 87.2 96.3 51.7 78.4 94.2 98.2 56.2 82.8 87.0 91.4 50.3 76.3 83.0 84.4 49.2 72.4 81.5 93.5 49.9 74.5 79.9 86.1 43.6 69.9
250 280 160 230 260 270 200 240 260 280 190 240 250
17 19 11 16 18 19 14 16 18 19 13 16 17 20 12 16 16 16 9 14 15 18 12 15
6 7 2 2
1
480 560 325 455 500 530 340 455 510 560 310 460 470 530 300 430 450 490 280 410 400 460 300 390
33 7 39 4 22 8 32.0 35 2 37 3 23 9 32 0 35.9 39 4 21 8 32.3 33.0 37 3 21 1 30.2 31 6 34 4 19 7 28 8 28 1 32 3 21.1 27 4
1167 1220 690 1025 1110 1170 660 950 1157 1240 610 1000 1047 1140 610 930 1043 1065 560 890 903 940 560 800
82.0 85 8 48.5 72.1 78.0 82 3 46 4 66.8 81.3 87.2 42.9 70.3 73.6 80.1 42 9 65.4 73.3 74.9 39.4 62.6 63.5 66.1 39.4 56.2
2400 2480 1450 2110 2410 2420 1450 2090 2440 2500 1440 2120 2230 2290 1330 1950 2230 2200 1260 1900 2050 2110 1230 1800
168.7 174.3 101.9 148.3 169.4 170.1 101 9 146.9 171.5 175.8 101,2 149.0 156.8 161.0 93.5 137.1 166.8 154.7 88.6 133.6 144.1 148.3 86.5 126.5
490 480 260 410 460 470 280 400 430 470 280 390 420 450 280 380 390 430 260 360 400 380 230 340
34 4 33 7 18 3 28.8 32 3 33 0 19 7 28 1 30 2 33 0 19 7 27.4 29 5 31 6 19 7 26 7 27 4 30 2 18 3 25 3 28 1 26 7 16 2 23 9
1050 1040 520 870 960 990 530 830 880 950 530 790 880 970 510 790 840 860 480 730 870 830 430 710
73.8 73.1 36.6 61.2 67.5 69.6 37.3 58.3 61 9 66.8 37.3 55,5 81.9 68.2 35 9 55.5 59 1 60 5 33 7 51 3 61 2 58 3 30 2 49 9
2180 2050 1140 1790 2050 1980 1110 1710 1890 1930 1060 1630 1980 1950 1080 1670 1830 1830 1010 1560 1950 1860 970 1590
153.3 144.1 80.1 125.8 144.1 139.2 78.0 120.2 132.9 135.7 74.5 114.6 139.2 187.1 75.9 117,4 130.1 128. ti 71.0 109.7 137.1 130.8 68.2 111.8
450 460 270 393 450 450 260 390 430 460 250 380 410 450 230 360 360 400 217 330
31 6 32 3 19 0 27 6 31.6 31.6 18.3 27.4 30 2 32 3 17 6 26 7 28 8 31 6 16.2 25.3 25 3 28.1 15.3 23.2
910 870 490 760 916 900 470 760 853 880 470 730 875 860 420 720 720 760 400 630
64 0 61.2 34.4 53.4 64.4 63.3 33.0 53.4 60.0 61.9 33.0 51.3 61.5 60.5 29.5 50.6 50.6 53.4 28.1 44.3
1900 1880 1040 1610 1910 1870 990 I590 1860 1860 1000 1570 1870 1860 930 1550 1570 1740 860 1390
133.6 132.2 73.1 113.2 134.3 131.5 69.6 111.8 130.8 130.8 70.3 110.4 131.5 130.1 65.4 109.0 110.4 122.3 60.5 97.7
290 180 240 240 240 130 200 220 260 215 170 250 250 140 210
40
1257
3
0 1 9 3 7 4 9 6 4 7 9 9 9 1 1 5 3 0
234.1 228.5 237 6 233 4 241 8 232 7 228 5 234.1 248 2 225 7 220 2 231 3 229 9 241 1 232 0 234 1 243 2 231 3 215 8 229 9
220 180 240 270 160 220 240 260 160 220 210 240 170 210 215 200 120 180
17 6 17 6 9 8 14 8 18 3 17 6 11 2 15 5 16 9 19 0 11 2 15 5 16 9 18 3 11 2 15 5 14 8 16 9 12 0 14 8 15 1 14 1 8 4 12 7
243 9 233 4 241.1 239.7 227.1 221.4 236.9 228.5 227.8 227.1 239.0 231.3 235.5 218.8 234.1 228.5 228.0 227.1 230 6 228.5
220 240 140 200 220 260 110 190 230 250 140 210 250 260 130 210 210 220 140 190
15 5 16 9 9.8 14.1 15.5 17 6 7.7 13.4 16 2 17 6 9.8 14.8 17.6 18 3 9,1 14.8 14.8 15 5 9.8 13.4
250 260
(Continued on next $age)
209.5 190.5 112.5 170.8 201.1 187.0 127.9 172.2 187.7 183.5 110.7 160.6 184.9 183.5 112.5 160.3 175.8 183.5 117.0 158.9 178.6 184.9 106.2 156.8
INDUSTRIAL AND ENGINEERING CHEMISTRY
1 2 s Table VIII-Effect
Hu-
FOR-
HIDITY
"C. 35
100
1 2 3 Av.
Lbs./in.' 3170 8190 3200 3190
0
1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av. 1 2 3 Av.
3320 3360 3420 3370 3140 3090 3320 3180 3126 2995 3310 3140 3026 2990 3320 3110 3086 3030 3220 3110 3120 3050 3250 3140
MULA
%
of Humiditg: Average of Three Middle Cures of Formulas 1, 2, a n d 3-(Continued) TENSILE AT ELONGATION OF:
FINALTENSILE
TEMP.
VOl. 20, No. 11
300%
Kg.lcm.2 229.9 224 3 225.0 224.3
Lbs./in.Z 210 230 130 190
233 4 236 2 240 4 236.9 220.7 217.2 233.4 223.8 219.8 210.5 232.7 220.7 212.7 210.2 233 4 218.6 216 9 213 0 226 4 218 6 219 3 214.4 228.5 220.7
240 250 150 210 240 260 140 210 210 230 120 190 230 240 120 200 210 240 140 200 240 360 120 210
500 %
400%
Kg.lcm.2
ti::
1
13.4
Lbs./in.l 360 390 230 330
Kg.lcm.8 25.3 27.4 16.2 23.2
Lbs./in.* 700 710 370 590
460 450 280 400
31 6
32 3
870 -. . 870 470 740 800 850 470 ,710 790 780 430 670 760 790 450 670 700 700 390 600 650 6iO 360 550
Kg./cm.l 49.2 49.9 26.0 41.5
1660 1650 810 1370
116.7 116.0 56.9 96.3
61.2 61.2 33.0 52.0 56.2 59.8 33.0 49.9 55.5 54.8 30.2 47.1 53.4 55.5 31 6 47.1 49.2 49.2 27.4 42.2 45.7 45.7 25.3 38.7
1840 1710 980 1310 1600 1710 930 1410 1640 1640 870 1380 1620 1610 900 1370 1440 1400 780 1210 1370 1370 760 1170
129.4 120.2 68.9 106.2 112.5 120.2 65.4 99.1 115.3 115.3 61.2 97.0 113.9 113.2 63.3 96.3 101.2 98.4 54.8 85.1 96.3 96.3 53.4 82.3
~
45
20
40
60
80
100
Table IX-Effect
Hn-
TEw'
MIDITY
OC.
%
5
0 20
FORMULA
5
40 60 80
Av. 4 5 Av. 4 5 Av . 4 5
100
15
0 20
40 60 80 100
25
0
Av . 4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av.
a
Av. 4 5 Av. 4 5
20
Av. 4
40
Av. 4
5 5
Av.
60 80 100
4 5
Av. 4 5 AV. 4 5 Av.
16.9 18.3 9.8 14.8 14.8 16.2 8.4 13.4 16.2 16.9 8.4 14.1 14.8 16 9 9.8 14.1 16.9 18.3 8.4 14.8
I 1
19 7 28 1 30 2 32 3 19 0 27 4 30 2 31 6 16 2 26 0 29 5 30 2 19 0 26 0 27.4 28.1 16.9 23.9 26.7 27.4 16.2 23.2
420 430 270 370 390 400 240 340 380 390 230 330
I
of Humidity: Average of Three Middle Cures of Formulas 4 a n d 5
TENSILE AT
-
FINAL TENSILE 200%
LbsJin.2 4 5 Av. 4
16 9
:14'o E8
JNGATION OF:
300%
400%
500%
4325 4750 4540 4530 4757 4640 4495 4730 4610 4415 4660 4540 4425 4850 4640 4450 4710 4580
304.0 333 9 319.2 318.5 334.4 326.2 316.0 332.5 324.1 310.4 327.6 319.2 311.1 341.0 326.2 312.8 331.1 322.0
LbsJin.2 850 670 760 900 680 790 850 650 750 810 665 740 880 670 775 800 675 730
4290 4513 4400 4190 4500 4340 4370 4560 4465 4300 4580 4440 4270 4610 4440 4350 4480 4415
301.6 317.3 309.3 294.6 316.4 305.1 307.2 320.6 313.9 302.3 322.0 312.1 300.2 324.1 312.1 305.8 314.9 310.4
800 670 735 770 610 690 820 660 740 790 640 715 800 640 720 830 630 730
56.2 47.1 51.7 54.1 42.9 48.5 57.6 46.4 52.0 55.5 45.0 50.3 56.2 45.0 50.6 58.3 44.3 51.3
1520 1340 1430 1500 1250 1375 1590 1350 1470 1520 1300 1410 1510 1320 1415 1550 1250 1400
106.9 94.2 100.5 105.5 87.9 96.7 111.8 94.9 103.3 106.9 91.4 99.1 106.2 92.8 99.5 109.0 87.9 98.4
2390 2230 2310 2413 2130 2280 2503 2230 2370 2367 2150 2260 2370 2180 2275 2390 2130 2260
168.0 156.8 162.4 169.6 149.7 160.3 176.0 156.8 166.6 166.4 151.1 158.9 166.6 153.3 159.9 168.0 149.7 158.9
3435 3230 3330 3470 3160 3310 3560 3590 3575 3400 3210 3305 3435 3210 3320 3490 3150 3320
241.5 227.1 234.1 243.9 222.1 232.7 250.3 252.4 251.3 239.0 225.7 232.3 241.5 225.7 233.4 245.3 221.4 233.4
293.2 305.1 299.1 294.6 313.5 304.0 283.3 309.3 296.3 297.4 307.9 302.6 293.9 299.5 296.7 296.7 310.7 303.7
730 590 660 760 610 685 720 570 645 710 540 625 720 510 615 650 530 590
51.3 41.5 46.4 53.4 42.9 48.2 50 6 40.1 45.3 49.9 38.0 43.9 50.6 35.9 43.2 45.7 37.3 41.5
1380 1220 1300 1380 1220 1300 1370 1100 1235 1340 1160 1250 1340 1100 1220 1260 1120 1190
97.0 85.8 91.4 97.0 85.8 91.4 96.3 77.3 86.8 94.2 81.5 87.9 94.2 77.3 85.8 88.6 78.7 83.7
2180 2000 2090 2210 1990 2100 2130 1950 2040 2150 1980 2065 2150 1890 2020 2070 1870 1970
153.3 140.6 146.9 155.4 139.9 147.6 149.7 137.1 143.4 151.1 139.2 145.2 151.1 132.9 142.0 145.5 131.5 138.5
3160 2960 3060 3150 2920 3035 3070 2870 2970 3130 3010 3070 3130 2870 3000 3080 2830 2955
222.1 208.1 215.1 221.4 205.3 213.4 215.8 201.8 208.8 220.0 211.6 215.8 220.0 201.8 210.9 216.5 198.9 207.7
4170 4340 4255 4190 4460 4325 4030 4400 4215 4230 4380 4305 4180 4260 4220 4220 4420 4320
Kg./cm.!
.
Kg./cm.*
187.7 172.2 180.0 193.3 175.8 184.5 190.5 174.0 182.1 188.4 168.7 178.6 191.2 173.6 182.1 176.2 168.0 172.2
Lbs./in.a 3740 3590 3665 3845 3630 3740 3770 3620 3690 3750 3495 3620 3840 3638 3740 3600 3490 3540
Kp./cm.a 262.9 252.4 257.6 270.3 255.2 262.9 265.0 254.5 259.4 263.6 245.7 254.5 270.0 255.8 262.9 253.1 245.3 248.9
Kg./cm.n
111.1 101.9 106.5
LbsJin.3 2670 2450 2560 2750 2500 2625 2710 2475 2590 2680 2400 2540 2720 2470 2590 2507 2390 2450
59.8 47.1 53.4 63.3 47.8 55.5 59.8 45.7 52.7 56.9 46.7 52.0 61.9 47.1 54.5 56.2 47.5 51.3
LbsJin.1 1680 1460 1570 1720 1460 1590 1650 1450 1550 1625 1435 1530 1690 1460 1575 1580 1450 1515
K.dcm.1 118.1 102.6 110.4 120.9 102.6 109.0 116.0 101.9 109.0 114.2 100.9 107.6 118.8 102.6 110.7
I N D Uh'TRIAL A N D ENGINEERING CHEMISTRY
November, 1928 Table IX-Effect ~~~
1259
of Humldity: Average of Three Middle Cures of Formulas 4 a n d (i-(Continrtcd)
~
TEMP. H ~ M X D IFORMULA TY
T E N W EAT ELONOATION OF:
FINALTBNSILB
200% 0
c.
%
35
0
O0 40 60 80 100
0
45
20 40 60 80 100
Table X-Effect
I
300%
Kg./cm.' 271.4 305 1 288.2 266.4 291.7 279.1 269.2 297 4 283.3 272.8 295 3 284.0 272.1 294.6 283.3 275.6 293.9 281.2
LbsJin.2 730 510 620 700 470 585 700 550 625 680 470 575 670 490 580 650 480 565
KgJcm.2 51.3 35.9 43.6 49.2 33.0 41.1 49.2 38.7 43.9 47.8 33 0 40.4 47.1 34.4 40.8 45.7 33.7 39.7
Lbs./in.r
Kg./cm.z
4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av. 4 6 Av.
LbsJin.2 3860 4340 4100 3790 4150 3970 3830 4230 4030 3880 4200 4040 3870 4190 4030 3920 4180 4000
1280 1100 1190 1260 1020 1140 1240 1030 1135 1210 1000 1105
4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av. 4 5 Av.
3540 4160 3850 3520 4140 3830 3450 4050 3750 3670 4060 3865 3490 3950 3720 3490 4020 3755
248 9 '292.4 270.7 247 5 291.0 269.2 242.5 284.7 263 6 268.0 285.4 271.7 245.3 277.7 261.5 245 3 282.6 264.0
710 500 605 680 510 595 660 500 580 680 480 580 630 460 645 610 440 525
49.9 35.2 42.5 47 8 35.9 41.8 46.4 35.2 40.8 47.8 33.7 40.8 44.3 32.3 38.3 42.9 30.9 36.9
1270 1040 1155 1200 1030 1115 1190 1020 1105 1220 980 1100 1140 950 1045 1130 910 1020
I
400%
600%
90.0 77.3 83.7 88.6 71.7 80.1 87.2 72.4 79.8 85.1 70.3 77.7
LbsJin.2 2030 1740 1885 2030 1710 1870 1980 1830 1905 1970 1710 1840 1970 1740 1855 1900 1690 1795
Kdcm.2 142.7 122.3 132.5 142.7 120.2 131.6 139.2 128.6 134.0 138.5 120.2 129.4 138.5 122.3 130.4 133.6 118.8 126.2
Lbs./in.* 2890 2610 2750 2910 2570 2740 2860 2730 2795 2840 2570 2705 2840 2610 2725 2780 2550 2668
Kg./cm.* 203.2 183.5 193.3 204.6 180.7 192.6 201.1 191.9 196.5 199.7 180.7 190.2 199.7 183.5 191.6 195.4 179.3 187.6
89.3 73.1 81.2 84.4 72.4 78.4 83.7 71.7 77.7 85 8 68.9 77.3 80.1 66.8 73.5 79.4 64.0 71.7
1940 1720 1830 1880 1710 1795 1810 1660 1735 1850 1630 1740 1740 1600 1670 1780 1520 1650
136.4 120.9 128.6 132.2 120.2 126.2 127.2 116.7 122.0 130.1 114.6 122.3 122.3 112.5 117.4 125.1 108.9 116.0
2770 2570 2670 2680 2550 2615 2620 2410 2515 2650 2400 2525 2520 2360 2440 2530 2290 2410
194.7 180.7 187.7 188.4 179.3 183.8 184.2 169.4 176.8 186.3 168.7 177.5 177.2 165.9 171.5 177.9 161.0 169.4
I
of H u m i d i t y a n d Temperature, Average Tensile6 a n d Moduli of Five Formulas (500 Per C e n t Moduli of Formulas 1, 2, a n d 3, a n d 400 Per Cent ,Moduli of Formulas 4 a n d 5). Average of Three Middle Cures of Each Formula
RELATIVE HUMIDITY
450 c.
+./
% 0 20 40 60 80 100
3974 3873 3917 3786 3850 3724
279.4 279.3 275 4 266 2 270 7 261.8
3864 3747 3761 3730 3779 3705
271.6 263.4 264.4 262 2 265.7 260.5
3669 3720 3685 3695 3687 3692
257.9 261.5 259.1 259 8 259 2 259.5
3685 3538 3586 3568 3562 3534
259.1 248.7 252.1 250.8 250.4 248.4
3559 3442 3388 8415 3356 3386
Part 11-Effect
of T e m p e r a t u r e a n d Relative H u m i d i t y a f t e r Mixing b u t Prior to Vulcanization
PROCEDURE-The same five formulas were used as in Part I. The materials used in the compounding were all from the same source, so that possible variations due to slight differences in ingredients might be eliminated. The rubber was taken from three different lots of selected smoked sheets a t the Fisk Rubber Company. A bale from each lot was washed on a four-roll washer and dried. The 600 pounds (272.4 kg.) of washed rubber were then blended in a Banbury mixer and sheeted on a mill. The batches were mixed a t the Bureau of Standards on a 24inch (61-cm.) mill. In each case the batches were compounded with 15 pounds (6.8 kg.) of the blended rubber. Formulas 1, 2, and 3 were given a milling time of 23 minutes while formulas 4 and 5 required 45 minutes owing to the larger amounts of compounding materials used. The mill used for this work is equipped with a rheostat so that the speed may be varied. After the batch was mixed, the speed was decreased and the rolls set to give a sheet approximately 0.085 inch (2.159 mm.) thick. This could be easily regulated so that the finished sheet did not vary more than "0.003 inch (0.0762 mm.) from edge to edge. The sheet was immediately cut into slabs of the correct dimensions and weight to give proper overflow and insure uniform curing conditions. The slabs were immediately placed in the cabinets for conditioning. The conditioning was carried out in small wooden chambers which were coated inside with paraffin t o insure against leaks and the doors when closed were sealed with tape and coated with melted paraffin. The slabs were placed on galvanized screens (6-mesh) in the chambers and the desired relative humidities
250.2 242.0 238.2 240.1 256.0 238.0
1692 1756 1687 1631 1677 1575
95.5 93.9 90.5 91.2 87.6 85.2
1206 1205 1202 1164 1117 1072
84.8 84.7 84.5 81.8 78.5 75.4
on.= 1175 1141 1092 1095 1023 991
K8.i cm. 82.6 80.2 76.8 77.0 71.9 69.7
maintained by the use of sulfuric acid solutions. The accuracy of the relative humidities obtained was checked with wet- and dry-bulb thermometers and was maintained within *3 per cent of the desired humidity. The relative humidities used were 10, 40, 70, and 100 per cent at each of the three temperatures 59". 77', and 95" F. (15', 25', and 35" (2.). These three temperatures were obtained simultaneously by using larger cabinets (Photograph 3) in which were placed the smaller humidity chambers. The room which served as one cabinet was maintained a t 59" F. (15' C.) and contained four of the humidity chambers a t that temperature. The 77' F. (25' C.) and 95" F. (35 O C.) temperatures were obtained in two cabinets by auxiliary heating and were controlled by thermostats. An electric fan in each cabinet circulated the air about the four chambers inside so that the desired temperature, as determined by measurements at the top and bottom of the cabinets, was maintained within 2 O F. (10 C.). Vulcanization of the samples was carried out in a platen press provided with four platens, thus giving three spaces for molds. Four-cavity aluminum frames placed between aluminum sheets 0.010 inch (0.254 mm.) thick were used as molds. Thus test sheets 6 by 6 inches (15.2 by 15.2 cm.) of quite uniform gage were obtained, most sheets not varying more than 0.002 inch (0.051 mm.) from edge t o edge. Six test specimens were died from each sheet and each specimen was tested. The temperatures of the platens were measured with mercury thermometers and thermocouples which checked as closely as the thermometer could be read. The greatest variation found was 0.5' F. (0.28' C.). Three periods of vulcanization were used for each formula, but all slabs for one period were cured simultaneously since there were twelve cavities available and twelve slabs required for ob-
IATDUXTRIAL A N D ENGINEERING CHEMISTRY
1260 ~
____
- ~-
I
RELATIVE HUMIDITY BEFORE VULCANIZATION I - 10% R E L H U M
2-40%
n
1
3 - 7 0 % R E L HUM
4-100%
**
41
FORMULA#I FIGURES A R E AVERAGE O F 3 C U R E S TESTE9 AFTER 2 DAYS AT 2 5 % AND 8 0 % R E L A T I V E H U M I D I T Y
PER C E N T ELONGATION C H A R T 14
VOl. 20, No. 11
slabs were allowed to stand for approximately a month before testing. Prior to testing, the cured slabs were conditioned for 2 days a t 80 per cent relative humidity a t 77' F. (25' C ). These conditions were chosen arbitrarily, so that after curing and during testing the slabs would receive the same treatment. The slabs were tested in the order in which they were vulcanized, so that approximately the same period of time elapsed in each case between vulcanization and testing. Asidesfrom the results shown by data in charts and tables, several observations of interest were made. Compound 1, which is the only one which is not dark colored, showed some interesting color changes due to variations in the humidity-the higher the humidity the darker the vulcanized slab. It was possible, by arranging in order of color, to place the sheets in their proper order in reference to humidity and temperature without observing the labels. It was also noted that slabs exposed to 100 per cent relative humidity showed a tendency to form surface pits, which appeared as though steam had been trapped during cure. These slabs were moist when removed from the humidity boxes, but all surface moisture was wiped off before vulcanizing. RESULTS-With formulas 1, 2, and 4 there is a softening of the compounds, as shown by the stress-strain curves, as the relative humidity increases, while with formulas 3 and 5 the compounds stiffen with an increase in relative humidity. (Tables X I to XV and Charts 14 t o 23, inclusive) The effect of the relative humidity is more pronounced the higher the temperature, which is to be expected since the absolute humidity is higher a t higher temperatures with corresponding relative humidities. There is a remarkable difference in the degree of the effect of humidity upon the similar compoundq4 and 5 as well as in the direction of the effect. I t is gener-
direction as the moduli, although not to so great a deeree. In order to find the more general effect of relative humidity, the averages of the results with the three I - IO%REL.HVM. 3-?0%REL.HUM. cures and the three temperatures were made and are 2 - 4 0 % ~ ~ 4-1007< given in Tables XVI and XVII and Chart 24. FORMULA +Z The effect of temoerature without reference to humidity is rather difficdt to obtain from the data at hand, since the effects of humidity are very closely connected with the temperatures. Although the relative humidities were of corresponding values a t the different temperatures, the amounts of moisture per given volume of air were widely divergent. Tables XVIII and X I X and Chart 25 show the effect of temperature by averaging the three cures and fotir relative humidities. The effect of temperature is small compared with that of relative humidity and appears t o be in the same direction as that of humidity with each of the compounds Since the effect of humidity varies with the compound, and in this case masks the temperature effect, it is concluded from these data that the effect of temperature i s n e g 1i g i b 1e . Subsequent data substantiate this claim. The tables and charts given so far in Part I1 have only to do with 2-day exposures. The results obtained with 12-day expnsures are shown in Tables XX and X X I and Charts 26 and 27, and it will be seen that the variations are in the same direction as with the 2-day exposure. There is a slight difference in the degree of v a r i a t i o n s with humidity and temperature. These tables and charts show the average variations of the final tensile and one modulus of each compound with relative humidity and temperature. I CoNcLusroNs-The effect of relative humidity before 300 400 500 600 700 800 300 4 0 0 500 600 700 800300 400 500 600 700 800 vulcanization dependsboth in degree and kind upon the PER CENT ELONGATION nature of the compound. A change of 30 per cent relaC H A R T 15 tiw mav cause a n effect in the physical -. - humiditv . . . properties cdrresponding to a 20 per cent change in taining the necessary data-three conditioning temperatures time of cure. The results of this investigation suggest that the effect may be dependent upon the accelerator used as well as with four humidities at each temperature. Since preliminary experiments showed that raw stock continues u p o n t h e compounding ingredients. Mercaptobenzothiazole t o adsorb moisture a t an appreciable rate for approximately 12 causes a stiffening, as shown by the stress-strain cwve, while days, exposures were made for 2 and 12 days previous to vul- di-o-tolylguanidine causes a softening. The effect of temperature is not so marked in general as th: efcanization. (Chart 13) The 2-dqy period approximates general practice in the industry while the 12-day exposure represents fect of relative humidity-a change in temperature of 18 F. close to the maximum effect. Slabs for all exposures were ob- (10' C.) causing a change in physical properties correspondtained from the same batch and after vulcanization the cured ing in some instances to as high as 15 per cent in time of cure
I
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZATION I)
:-
1
Xovember. 1928
IND USTRIAL AND ENGINEERING CHEMISTRY
but usually causing a practically n e g 1 i g i b 1 e change. T i m e Factor in Conditioning R a w Stock Previous t o Vulcanization
1261
E FF€CT OF RELATIVE HUMIDITY BEFORE VULCANIZATION I-IO%RELHUM 2-40% y
3 - 7 0 % R E L HUM 4-100% u 18
I I
The periods of exposure in Part I were 2 and 6 FORMULA days, while in Part I1 the periods were 2 and 12 TIGURES ARE A V E R A G E O F THREE C U R E S I days. These periods were chosen from a study T E S T E D A F T E R 2 D A Y S AT 25°C AND B O % R E L A T I V E H U l Y l D i T Y I of the adsorption curves (Charts 1 and 13) to determine the effects during a period comparable to general practice in the industry and during a period which might give approximately maximum effects. It was later decided that a 24-hour aging period was more generally used than a 48hour period. A series of experiments was made to determine the effect of the time of exposure and of delays in vulcanizing the raw compounds after removal from the conditioning cabinets. Formula.: 2, 3 , and 5 mere used in this work. Each compound was mixed and carried through the conditioning schedule previous to vulcanization by itself. After mixing and sheeting, the slabs were immediately cut to the desired dimension< and placed in the conditioning chambers, where they were exposed to a relative humidity of 55 per cent a t 82" F. (27.8' C ). Slabs were removed for curing after 6 hours' conditioning After 24 hours slabs were removed and some of them placed in other conditioning boxes to give 10 and 100 per cent relative humidities for l / * , I , 2, and 6 hours each. This same procedure was repeated after 48 hours a t 55 per cent relative humidity a t 82' F. (27.8' C.). In addition, after 48 hours' conditioning, two slabs were vulcanized a t once, one to be tested after 24 hours a t 55 per cent relative humidity a t 82' F (27.8' C.) and the other after 48 hours under the same conditions. This scheme was followed with each of the three compounds Before testing in each EFFECT OF RELATIVE HUMIDITY case, the specimens were conditioned for 48 hours a t 55 BEFORE VUL CANlZ ATlON per cent relative humidity a t 82" F. (27.8" C.) unless I - I O % R E L HUM 3 - 7 0 % R E L H U M 4 otherwise stated. 2-40%48 4-100%,8 Small sample5 of the raw stock were removed a t intervals from the conditioning chambers and weighed to determine FORMULA .#. 4 the amount of moisture taken up during the exposure. % ' FIGURES A R E A V E R A G E O F 3 CURES REsuLTs-l'able XXII (Charts 28 and 29) represents TESTED A F T E R 2 DAYS AT 25OC A N D 80% R E L A T I V E H U M I D I T Y the values of the final tensiles and various moduli obtained, respectively, with compounds 2 , 3 , and 5 . I n Table XXIII (Chart 30) are collected thr data to show variations of the three compounds with length of exposure to the one set-of conditions. CoxcLusroxs-It is evident that after removal from the conditioning cabinets under ordinary conditions, an elapsed time of an hour before vulcanization would not materially alter the final properties after vulcanization. I t is also evident that a 24-hour period of conditioning previous to t e s h g is just as satisfactory as a 48-hour period. This would probably not be true, however, if the conditioning were done under extremes of either relative humidity ,or temperature ranges. The length of exposure of raw stock is important and a definite standard should be set up-48 hours could not be interchanged with 24 hours, although an hour or so either way would not materially change the physical properties of the vulcanized specimens. Hence the recommendation of 26 * 2 hours for conditioning uncured stock.
#3
18
Effects of Relative H u m i d i t y before Mixing
It was desired to determine the effect, if any, of exposing the ingredients of rubber compounds to atmospheres of various relative humidities before the mixing period The five formulas used in the previous work were used. The four relative humidities used were 0, 35, 65, and 100 per cent a t 82" F. (27.8" C.). The ingredients were exposed to these various conditions for a period of 6 days prior to mixing. After mixing and sheeting, the samples were exposed for 2 days to 55 per cent relative humidity a t 82" F. (27.8' C.) before vulcanization. The vulcanized specimens were also given a 2-day exposure to 55 per cent relative humidity at 82" F. (27.8" C.) before being tested a t t h a t temperature. In order t h a t the compounds should be identical except for the moisture present in the ingredients, it was necessary to correct to
a standard. For this purpose it was assumed that the formulas are based on dry weights. The dry weight was taken as t h a t after exposure fof 6 days over concentrated sulfuric acid at 8&,SF. (27 8" C.). I t is, of course, possible t h a t small amount$ of moisture were still retained after these conditions were imposed upon the materials
INDUSTRIAL AND ENGINEERING CHEMISTRY
1262
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZATION I
I - I O % R E L HUM. 3 - 7 0 % R E L H U M 2-40% I I* 4 -100%
i
IS
II
FOR MULA #5
I
I
i
I
TESTED
I
EFFECT OF RELATIVE HUMIDITY BE FOR E VULCAN I2AT ION FULL L I N E S = F I N A L T E N S I L E S I = 400 %MODULUS 2 =SOOXMODULUS 3 = 600% *4 -700%
FORMULA
18
FORMULA+Z
In compounding the stocks, the various materials in more than sufficient quantity for each batch were exposed for 6 days to the various humidities and then corrections applied based on the moisture determinations a t these humidities.
I =300%MODULUS FULL LINES = F I N A L T E N S I L E S 2-400%MODULUS 3 =500%MODULUS '4 = 600781 5 ~700% ti FIGURES ARE AVERAGE O F T H R E E CURES T E S T E D A F T E R 2 DAYS A T 25'C. AND B O X REL.HUM.
FULL L I N E S = F I N A L T E N S I L E S I -300%MODULUS 2=400%?lODULUS 3 = 5 0 0 % MODULUS 4=600X S = 700% 8. F I G U R E S A R E AVERAGE O F 3 C U R E S T E S T E 0 A F T E R 2 DAYS A T 2 5 ' C . A N D 8 O X R E L . H U M .
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZATION FORMULA+ I
FIGURES ARE A V E R A G E OF 3 C U R E S A F T E R 2 DAYS A T 2 5 " C . A N D B O % R E L A T I V E H U M I O I T Y 1
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZATION
Vol. 20, No. 11
+3
18
FIGURES A R E A V E R A G E OF 3 CURES T E S T E D AFTER 2 D A Y S A T 2 5 ' C . A N D 80%REL.HUM.
Table XXIV gives the per cent moisture in each of the ingredients after exposure for 6 days at 82' F. (27.8' C.). It is evident that at 100 per cent relative humidity, proportionately more taken UD than at 35 and 65 per cent, respectively. moisture is .~ ~
INDUSTRIAL A N D ENGINEERING CHEMISTRY
November, 1928
FULL L I N E S = F I N A L T E N S I L E S 1'200%MODULUS 3 = 400XMODULUS 2 = 300% MODULUS 4 =500,% I( 5 =600%
FORMULA
IO
40
70
+4
-
100 I O 4 0 10 I O 0 I O 40 70 PER C E N T R E L A T I V E HUnlDlTY
1263
E F F E C T OF RELATIVE HUMIDITY BEFORE VULCANIZATION FULL L I N E S = F I N A L T E N S I L E S 1=200% MODULUS 3 =400% MOL>ULUS 2 = 300 % M O D U L U S 4=500% .a 5=600% &I
FORMULA
5
F I G U R E S A R E A V E R A G E OF 3 C U R E S T E S T E D AFTER 2 DAYS A T 2 5 ° C . AND BO%REL
HUM.
'
LOO
CHART 2 2
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZATION FULL LINES=FINAL TENSILES I=EOO%MODULUS 2=3OO%MODULUS 3=4OO%MODULUS 4 =SOO%MODULUS 5=600% MODULUS 6=700~MODULUS
Since the crude rubber was in slabs of from 0.5 t o 1 inch (1.3 to 2.5 cm.) in thickness, it was run three times through a moderately warm mill to make it more uniform before exposure. The
mill opening was 3 / 1 6 inch (4.7 mm.), so that a considerable surface for adsorption of moisture was supplied and was approximately the same for all batches.
INDUSTRIAL A N D ENGINEERING CHEMISTRY
1264
I
Vol. 20, No. 11
€FFECT OF TEMPERATURE BEFORE VULCANIZATION FULL LINES = F I N A L TENSILES I = 2 0 0 % M O D U L U S 2 = 3OO%MODULUS 3=400%MODULUS 4 = 5 0 0 % W O D U L l J S 5 = GOO%MODULUS 6 ; 700%flODULUS FIGURES A R E AVERAGE O F T H R E E CURES A T FOUR HUMIDITIES
4 FORMULA + 5
T E M P E R A T U R E IN D E G R E E S C E N T I G R A D E
CHART 25
Table XI-Part TBMP.
HUMIDITY CUR1
11, Effect of Humidity (Formula 1)
T
FINAL TENSILE 300%
MLE A T
ELONCATTON OF:
400%
500%
LbsJin.2 Kg./cm.' 200 14.1 340 23 9 400 28.1 310 21.8 220 15.5 320 22.5 400 28.1 310 21.8 200 14.1 340 23.9 400 28.1 310 21.8 180 12.7 280 10.7 370 26.0 280 19.7
Lbs./in.l Kg./cm.2 440 30 9 750 52 7 900 63 3 700 49 2 500 35 2 700 49.2
I
600% ~~
C. 15
% 10
40
70
100
25
10
40
70
100
35
10
40
70
100
Min.
Lbs./in.r
30 45 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av.
3550 3940 4020 3840 3580 4000 4100 3890 3380 4000 40RO 3820 3580 4100 4170 3950
30 45 _. 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av.
3920 4180 3990 4030 3880 3930 3910 3910 3570 3970 3950 3830 3540 3820 3870 3740
30 45 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45
3880 3980 3900 3920 ..~. 3300 4040 3850 3730 3300 3910 3750 3690 3160 3820 4040 a670
60 Av.
'
Kg./cm.' 24%6 277.0 282.6 270.0 251.7 281.2 288.2 273.5 237.6 281 2 286.8 268.5 251.7 288.2 203.2 277.7
LbsJin.2 Kn./cm.2 110 7 7 180 12.7 220 15.5 170 12.0 110 7 7 180 12.7 220 15.j 170 12.0 100 7.0 200 14.1 210 14.8 170 12.0 100 7.0 130 9.1 180 12.7 140 9.8
700 420 710 880 670 350 610 860 620
48.2 29.5 49.9 61.9 47.1 26 7 42 9 60 5 43 6
1
Lbs /zn.l 1110 1780 3200 1700 1200 1780 2180 1720 1100 1710 2130 1650 940 1480 2010 1480
Kg /cm.l 78 0 125 1 154 7 119 5 84 4 125 1 153 3 120.9 77 3 120 2 149.7 116 0 66.1 104.0 141.3 104 0 83.0 126.5 165.9 125.1 83.7 120.2 160.3 121.6 76.6 118.1 140.6 111.8
2530 3530 3990 3350 2520 3400 3910 3280 2320 3250 3740 3100 2020 2950 3800 2920
177.9 248.2 280.5 235.5 177.2 239.0 274.9 230.6 163.1 228.5 262.9 217.9 142.0 207.4 267.1 205.3
88.6 129.4 160.3 125.8 68.2 109.0 147.6 108.3 58.3 92.1 126.5 92.1 57.6 98.4 112.6 89.3
2660 3680 3900 3410 2170 3290 3860 3110 1800 2700 3530 2680 1780 2900 3320 2670
187.0 258.7 274.2 239.7 152.6 231.3 271.4 218.6 126.5 189.8 248.2 188.4 125.1 203.9 233.4 187.7
275.6 293.9 280.5 283.3 272.8 276.3 274.9 274.8 251.0 279.1 277.7 269.2 248.9 268.5 272.1 262.9
110 190 22 170 110 180 210 170 90 150 180 140 90 150 200 150
7.7 13.4 15.5 12.0 7.7 12.7 14.8 12.0 6.3 10.5 12.7 9.8 6.3 10.5 14.1 10.5
220 '380 420 340 220 300 400 310 200 300 380 290 170 250 400 270
15.5 26 7 29.5 23.9 15.5 21.1 28.1 21.8 14.1 21.1 26.7 20.4 12.0 17.6 28.1 19.0
480 760 1000 750 450 740 950 710
33.7 53.4 70.3 52.7 31.6 52.0 66.8 49.9
800 640
45.0
1180 1800 2360 1780 1190 1710 2280 1730 1090 1680 2000 1590
272.8 279.8 274.2 275.6 ~~. 232.0 284.0 270.7 262.2 232.0 274.9 263.6 259.4 222.1 268.5 284.0 258.0
110 180 210 170 100 130 200 140 90
7.7 12.7 14.8 12.0 7.0 9.1 14.1 9.8 6.3 7.7 12.7 9.1 5.6 7.0 9.1 7.1
220 350 390 320 200 300 390 300 170 230 360 250 160 220 300 230
15 5 24.6 27.4 22.5 14.1 21.1 27.4 21.1 12.0 16.2 25 3 17.6 11.2 15.5 21.1 16.2
480 750 900 710 380 620 850 620 320 520 780 640 300 550 630 490
33.7 52.7 63.3 49.9 26.7 43.6 50.8 43.6 22.5 36.6 54.8 38.0 21.1 38.7 44.3 34.4
1260 1840 2280 1790 970 1550 2100 1540 830 1310 1800 1310 830 1400 1600 1270
110
180 130 80 100 130 100
700% ~
Lbs./in.' 2400 3470 3960 3280 2500 3420 3909 3300 2270 3410 3000 3190 2000 3020 3870 2960
Kg./cm.l 108.7 243.9 278.4 230.6 175 8 240.4 280.5 232.0 159.6 230.7 274.2 224.3 140 6 212.3, 272.1 208.1
INDUSTRIAL AND ENGINEERING CHEMISTRY
November, 1928
1
TIME FACTOR IN EFFECT OF R€LATIVE HUMIDITY
EFFECT OF RELATIVE HUMIDITY BEFORE VULCANIZ AT1 ON
EFFECT OF TE M PE R ATU R E BE FORE VULCANIZATION
V A L U E S A R E AVERAGE O F 3 CURES A T 3 TEMPERATURES 4800 12 D A Y E X P O S U R E
V A L U E S ARE AVERAGE OF 3CURES A T 4 HUMIDITIES
I
i
1265
FORMULAS 2,3,AND5
EXPOSED T O 5 5 % R E L HUM A T 2 1 e 8 C
. ..., .,
I = F O R M U L A 2 FINRLTENSILE
2; 3 ; 4 = 5 =
7 6 ;= 8 . 9 -
I
10:
3
I.
i
1,
5 2 500% r l O 0 U L U S
I. .I
II .I
1 ,. 2 S S6C0O0Y%.
IS
3
%I
I, ,I
.
.,
1
5 500% z 700%
I.
"
I
K GS / b
4000
FlNRL TENSILE:,
rlNAL
TENSILES 250'
:
,l60LL___-i_--
goo
T E S T E D A F T E R 2 DAYS T 25°C AND 8 0 % R E L H U M
G O
I '
I
I
I
1
IO 40 10 100 PER CENT RELATIVE H U M I D I T Y
15 25 TEMPERATURE IN DEGRECS
CHART 2 6
TIME FACTOR IN EFFECT OF RELATIVE HUMIDITY
I
RAW S T O C K EXPOSED 2 4 H R S T 0 5 5 X R E L H U M AT27"BC A F T E R T H I S EXPOSURE SAMPLES W E R € T O 1 0 % , 5 5 % . A N D 100% R E L A T I V E H U M I D I T Y 2 i/ I H O U R 3; 2 H O U R S 4 = G H O U R S
SUBJECTED
I =I / Z H O U R
BEFORE TESTING E X P O S E D 2 D A Y S 5 5 % R E L H U M A T 2 7 O 8 C
35 CENTIGRADE
CHART 2 7
TIME FACTOR IN EFFECT OF RFLATIVE HUMIDITY
I
I
I I
I 1
R A W STOCK E X P O S E D 4 8 H O U R S T 0 5 5 X R E L HUM A T 2 7 O 8 C . AFTER T H I S EXPOSURE S A N P L E S WERE SUBJECTED TO l O % , S 5 % . A N D 100% RELATIVE Y U M I U I T Y 1=1/2UOuR
3=LYOURS
Z=lUOUR
4-6HOURS
BEFORE T E S T I N G EXPOSED2 D A Y S @ 5 5 % R E L HUN A T 2 7 O 8 C .
FORMULA+Z
'4400 CURE 4 5 M l N @ 1 4 l D l C
I
I !
ill
I I
Iz5'1
2 00
2400
-*--=--. ;y--==>
u IO
55
IO0
PER C E N T R E L A T I V E HUMIDITY CHART 2 8
10
55
100
PER
10
55
100
IO
C E N T R E L A T I V E HUMIDITY CHART 29
55
100
1
Vol. 20, No. 11
INDUSTRIAL An'D ENGINEERING CHEMIXTRY
1266
cnm-r
Table XII-Part
31
11, Effect of Humidity (Formula 2)
TENSILE AI ELONGATION
TE-.
oc. 15
HUMIDITYCURE
yo .. 10
40
70
100
25
10
40
Min. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av.
100
35
10
40
70
100
500%
300% Lbs./in.l Kg./cm.l 3260 229.2 3960 278.4 3790 266.4 3670 258.0 3500 246.1 3960 278.4 3790 266.4 3750 263.6 3370 236.9 3900 274.2 3890 273.5 3720 261.5 3370 236.9 3800 267.1 3860 271.4 3680 258.7
Lbs./in.l Kg./cm.l 110 7.7 180 12.7 200 14.1 160 11.2 110 7.7 180 12.7 200 14.1 160 11.2 110 7.7 160 11.2 190 13.4 150 10.5 110 7.7 160 11.2 190 13.4 150 10.5
200 310 400 300 200 300 400 300 200 290 400 300 200 290 380 290
14.1 21.8 28.1 21.1 14.1 21.1 28.1 21.1 14.1 20.4 28.1 21.1 14.1 20.4 26.7 20.4
LbsJin.1 Kg./cm.l 420 29.5 710 49.9 900 63.3 680 47.8 400 28.1 670 47.1 890 62.6 650 45.7 400 28.1 650 45.7 840 59.1 630 44.3 400 28.1 650 45.7 800 56.2 620 43.6
1000 1620 1970 1530 970 1520 1910 1470
70.3 113.9 138.5 107.6 68.2 106.9 134 3 103.3
1490 1940 1470
104.7 136.4 103.3
1470 1890 1450
103.3 132.9 101.9
A". 30 45 60 Av. 30 45 60 Av.
3750 3920 3910 3860 3620 3820 3890 3780 3400 3700 3800 3630 3380 3650 3720 3580
263.6 275.6 274.9 271.4 254.5 268.5 273.5 265.7 239.0 260.1 267.1 255.2 237.6 256.6 261.5 251.7
120 190 200 170 110 180 200 160 100 170 190 150 100 170 190 I50
8.4 13.4 14.1 12.0 7.7 12.7 14.1 11.2 7.0 12.0 13.4 10.5 7.0 12.0 13.4 10.5
240 370 410 340 220 330 400 320 200 310 360 290 190 290 330 270
16.9 26.0 25.8 23.9 15.5 23.2 28.1 22.5 14.1 21.8 25.3 20.4 13.4 20.4 23.2 19.0
500 790 950 750 470 730 900 700 420 660 800 630 390 630 760 590
35.2 55.5 66.8 52.7 33.0 51.3 63.3 49.2 29.5 46.4 56.2 44.3 27.4 44.3 53.4 41.5
1150 1730 2070 1650 1100 1640 1980 1570
80.8 121.6 145.5 116.0 77.3 115.3 139.2 110.4
1500 1730 1400 900 1470 1670 1350
105.5 121.6 98.4 63.3 103.3 117.4 94.9
30 45 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av.
3770 3760 3840 3790 3500 3690 3880 3690 3400 3700 3790 3630 3400 3500 3740 3550
265.0 264.3 270.0 266.4 246.1 259.4 272.8 259.4 239.0 260.1 266.4 255.2 239.0 246.1 262.9 ,249.6
120 170 210 167 120 170 210 167 110 140 200 150 110 110 180 130
8.4 12.0 14.8 11.7 8.4 12.0 14.8 11.7 7.7 9.8 14.1 10.5 7.7 7.7 12.7 9.1
220 330 410 320 200 330 410 310 200 300 380 290 180 270 330 260
15.5 23.2 28.8 29.5 14 1 23.2 28.8 21.8 14.1 21.1 26.7 20.4 12.7 19.0 23.2 18.3
500 750 910 720 470 700 890 690 410 660 790 620 370 580 740 560
35.2 52.7 64.0 50.6 33.0 49 2 62.6 48.5 28.8 46.4 55.5 43.6 26.0 40.8 52.0 39.4
1110 1700 2000 1600 1080 1650 1970 1570 1000 1460 1780 1410 910 1290 1620
78 0 119.5 140.6 112.5 75.9 116.0 138.5 110.4 70.3 102.6 125.1 99.1 64.0 90.7 113.9 89.3
30 45 60 Av. 30 45 60
70
FINALTENSILE
1270
-
2120 3170 3590 2960 2060 3040 3560 2890 2060 3020 3570 2880 2060 2900 3520 2830
i49.0 222.9 252.4 208.1 144.8 213.7 ,250.3 203.2 144.8 212.3 251.0 202.5 144.8 203.9 247.5 198.9
2310 3390 3740 3150 2210 3180 3680 3020 1980 2960 3470 2800 1870 2760 3350 2660
162.4 238.3 262.9 221.4 155.4 223.6 258.7 212.3 139.2 208.1 243.9 196.8 131.5 194.0 235.5 187.0
2270 3300 3720 3100 2180 3200 3700 3030 2000 2870 3410 2760 1790 2620 3180 2530
159.6 232.0 261.5 217.9 153.3 '225.0 260.1 213.0 140.6 201.8 239.7 194.0 125.81 184.2 223.6 177.9
I N D USTRIAL AND ENGINEERING CHEMISTRY
November, 1928
1267 ________..
I
I
O F 0.012 G R A M O F M O I S T U R E P E R L I T E R BEFORE T E S T I N G E X P O S E D 2 4 H O U R S T O 4 5 % R E L . H V M . @ Z 7 ? 8 C .
FORMULA#3
I
FORMULAii-4
ADSORPTION OF MOISTURE BY RAW S T O C K EXPOSED T O ABSOLUTE HUMIDITY OF .012 GRAM OF MOISTURE PER LITER
~
I = STOCKXJ
2 = STOCKX4
i
3 = STOCKX5
I FORMULA+S
0
B
16
24
0 8 16 24 HOURS E X P O S U R E
0
8
I6
24
CHART 33
As each batch came from the mill it was weighed t o determine the loss during milling. This loss of weight, of course, cannot be ascribed entirely to a loss in moisture, for small amounts of the ingredients are lost in the air. The figures are given in Table
xxv.
Table XXV (Chart 31) gives the stress-strain data obtained upon testing the specimens. Humidity before mixing seems to have no appreciable effect with compounds 1, 3, and 5 . The variations shown with compounds 2 and 4 may be experimental errors, since they are nearly within the usually recognized 5 per cent limit. There is no apparent reason why two of the stocks should show variations while three do not. Unless there is a material difference in the Table XIII-Part TEMP.HUMIDITY
CURB
11, Effect of Humidity (Formula 3) TENSILE AT ELONGATION OF:
FINALTENSILE
O
C.
15
% 10
40
70
100
25
10
40
70
Min. 40 60 90 Av. 40 60 90 Av. 40 60 90 Av. 40 60 90 Av.
40 60 90 Av. 40 60 90 Av. 40 60 90 Av.
35
.
100
40 60 90 Av.
10
40 60 90 Av. 40 60 90 Av. 40
40
70
60
100
90 Av. 40 60
90 Av.
LbsJin.2 Km./cm.r I. 3330 234.1 3540 248.9 3520 247.5 3460 243.2 3330 234.1 3340 234.8 3480 244.6 3380 237.6 3400 239.0 3740 262.9 3600 253.1 3580 251.7 3300 232.0 3740 262.9 3600 253.1 3550 249.6
I
400%
300% Lbs./in.l Kg./cm.r 80 5.6 90 6.3 100 7.0 90 6.3 80 5.6 90 6.3 100 7.0 90 6.3 100 7.0 100 7.0 100 7.0 100 7.0 100 7.0 100 7.0 100 70 100 7.0
Lbs./in.r Kg./cm.l 290 20.4 370 26.0 350 24.6 340 23.9 290 20.4 370 26.0 360 25.3 340 23.9 300 21.1 370 26.0 390 27.4 350 24.6 320 22.5 400 28.1 420 29.5 380 26.7
Lbs.lin.2 Kg./cm.r 150 10.5 180 12.7 200 14.1 180 12.7 150 10.5 180 12.7 200 14.1 180 12.7 150 10.5 180 12.7 210 14.8 180 12.7 160 11.2 200 14.1 230 16.2 200 14.1
3380 3680 3520 3530 3380 3680 3520 3530 3660 3790 3560 3670 3660 3790 3700 3720
237.6 258.7 247.5 248.2 237.6 258.7 247.5 248.2 257.3 266.4 250.3 258.0 257.3 266.4 260.1 261.5
70 80 100 80 70 80 100 80 100 90 100 100 110 110 100 110
4.9 5.6 7.0 5.6 4.9 5.6 7.0 5.6 7.0 6.3 7.0 7.0 7.7 7.7 7.0 7.7
150 180 180 170 150 180 180 170 180 200 200 190 220 230
3300 3480 3490 3420 3420 3530 3550 3500 3500 3650 3550 3570 3740 3590 3580 3640
232.0 244.6 245.3 240.4 240.4 248.2 249.6 246.1 246.1 256.6 249.6 251.0 262.9 252.4 251.7 255.9
80 80 90 80 80 80 90 80 110 110 110 110 110 120 120 120
5.6 5.6 6.3 5.6 5.6 5.6 6.3 5.6 7.7 7.7 7.7 7.7 7.7 8.4 8.4 8.4
140 170 200 170 140 170 200
170 180 200 200 190 190 240 220 220
'
10.5 12.7 12.7 12.0 10.5 12.7 12.7 12.0 12.7 14.1 14.1 13.4 15.5
I
500%
290 380 370 350 290 380 370 350
20.4 26.7 26.0 24.6 20.4 26.7 26.0 24.6
%
;28.8 ?:4"
600%
Lbs./in.n Kg./cm.r 670 47 1 760 53.4 750 52.7 730 51.3 670 47.1 760 53.4 790 55.5 740 52.0 700 49.2 800 56.2 830 58 3 780 54.8 780 54.8 880 61.9 940 66.1 870 61.2
410 370 400
26.0 28.1
16.2
430
30.2
650 780 780 740 700 780 780 750 720 820 880 810 870 950 990 940
9.8 12.0 14.1 12.0 9.8 12.0 14.1 12.0 12.7 14.1 14.1 13.4 13.4 16.9 15.5 15.5
280 340 380 330 280 340 380 330 320 400 400 370 360 480 470 440
19.7 23.9 26.7 23.2 19.7 23.9 26.7 23.2 22.5 28.1 28.1 26.0 25.3 33.7 33.0 30.9
620 760 780 720 680 790 820 760 780 870 900 850 880 1000 980 950
1
700%
1
45.7 54.8 54.8 52.0 49.2 54.8 54.8 52.7 50.6 57.6 61.9 56.9 61.2 66.8 69.6
Lbs./in.g Kg,/cm.a 1430 100.5 1510 106.2 1600 112.5 1510 106.2 1430 100.5 1560 109.7 1680 118.1 1560 109.7 1490 104.7 1700 119.5 1780 125.1 1660 116.7 1590 111.8 1820 127.9 1950 137.1 1790 125.8
66.1
1390 1680 1670 1580 1460 1700 1670 1610 1550 1770 1850 1720 1780 2000 2080 1950
97.7 118.1 117.4 111.1 102.6 119.5 117.4 113.2 109.0 124.4 130.1 120.9 125.1 140.6 146.2 137.1
43.6 53.4 54.8 50.6 47.8 55.5 57.6 53.4 54.8 61.2 63.3 59.8 61.9 70.3 68.9 66.8
1380 1560 1700 1550 1430 1650 1750 1610 1590 1800 1900 1760 1810 2080 2100 2000
97.0 109.7 119.5 109.0 100.5 116.0 123.0 113.2 111.8 126.5 133.6 123.7 127.2 146.2 147.6 140.6
IiVD USTRIAL A X D EiYGINEERING CHEMISTRY
1268
way in which the ingredients are dispersed due to their moisture content, the finished products should possess the same physical properties. Subsequent ta mixing the stocks were all subjected to a 2-day exposure to 55 per cent relative humidity a t 82" F. (27.8' C.), so that, even if one batch were of less moisture content than another of the same compound, this exposure would tend to bring them together so far as their water content is concerned. I t is concluded that ordinary storage conditions are satisfactory for crude rubber compounding ingredients. Effect of M a i n t a i n i n g a C o n s t a n t Absolute H u m i d i t y at Various T e m p e r a t u r e s Previous t o Vulcanization Previous work during this investigation upon the effect of temperature and relative humidity has shown conclusively that stocks exposed to different relative humidities before vulcanization vary considerably in physical prop rties after vulcinization. The direction and extent of these variations are dependent upon the compound. After vulcanization, relative humidity plays but a small part, while the temperature of the specimens and testing room must be controlled within quite narrow limits to escape undesirable variations due to differences in temperature. In endeavoring to find the effect of temperature alone upon the raw stock, calculations were made converting the relative humidities to the absolute values and using values found by interpolation I t appeared that, if the absolute humidity remained constant, the temperature of conditioning (within the studied range) had no effect upon the physical properties of the vulcanived compounds. In order to discover if this is true, a short study was made using compounds 3, 4, and 5, which have been used heretofore and showed large effects due to relative humidity variations. After mixing and sheeting to a thickness of 0.100 inch (2.54 mm.). the compounds were exposed for 24 hours to atmospheres giving an absolute humidity of 5.24 grains of moisture per cubic foot (0.012 gram moisture per liter) a t temperatures of 70" F. Table XIV-Part
TEMP. HUMIDITY CURE
c.
%
Min.
Av. 30 45 60 Av. 30 45 60 AV. 30 45 60 Av.
40
70
100
25
10
30 45 60 Av. 30 45 60 Av. 30 45 60 Av. 30 45 60 Av
40
70
100
.
(21.1' C.), 82" F. (27.8' C.), and 95" F. (35" C ) , respectively, which is equivalent to 65 per cent relative humidity a t 70" Fd Compounds 3 and 5 were vulcanized 60 minutes a t 259" F. (126.1 C . ) and compound 4 was vulcanized 45 minutes a t 287 O F. (141.7' C.). After curing, the specimens were exposed to an atmosphere of the same absolute humidity (5.24 grains of moisture per cubic foot) (0.012 gram moisture per liter) a t 82" F. (27.8' C.) and tested a t that temperature. The results are given in Table XXVII (Chart 32). The values of the various moduli and tensiles are the result of testing twelve specimens of each stock for each set of conditions. I t is evident from a study of the results that the physical properties of the vulcanized compounds are not affected by exposure of the raw stock to various temperatures, provided the absolute humidity is maintained constant. Simultaneously with the exposures of the ra& stock previous to curing, duplicate exposures were made with samples of the same compounds to determine by successive weighings the amount of moisture adsorbed over a 24-hour period a t each of the abovementioned conditions. The samples were allowed to cool in a desiccator before the initial weighings were made and were removed from the conditioning cabinets every 4 hours for weighing. The results ate shown in Table XXVIII (Chart 33). A study of both Tables XXV11 and XXVIII indicates that the rate of adsorption increases slightly with a decrease in temperature and the consequent increase in relative humidity. I t is evident, however, from the stress-strain data that this increase in the rate of adsorption is not sufficient during a 24-hour period to affect the physical properties of the vulcanizates to a n appreciable extent. J. E. PARTENHEIYER, Chairman E. R. BRIDCEWATERN. A. SHEPARD A. A. SOMERVILLE W. W. VOGT P. .I WORMELEY
D. F. CRAXOR E. B. CURTIS J. W. SCHADE
b
11, Effect of H u m i d i t y (Formula 4) TENSILEAT E L O N G A T ~OF: ON
FIXAL TENSILE
200R
Lbs./in.2 Kg.jcm.2 4200 301.6 4280 300 9 4200 295.3 4260 299.5 4220 296 7 4380 4340 4310 303 0 4130 290 3 4380 307 9 4220 296 7 4240 298 1 4240 298 1 4310 303 0 4200 295 3 4250 298 8
%.?
4230 4300 4220 4250 4230 4300 4170 4230 4240 4350 4200 4260 4170 4260 4050 4160
Vol. 20, No. 11
300%
7 1 8 1 7 1 8 1 9
33 47 59 47 33 47 59 47 30
440 620 780 610
30 9 4 6 52:8 42.9
480 600 820 630 480 600 820 630 440 620 800 629 440 620 800 620
33 42 57 44 33 42 57 44 36 43 56 43 30 43 56 43
3 9 6 2 6 9 6 2 6
930 1200 1430 1190 930 1200 1430 1190 920 1200 1420 1180 920 1200 1410 1180
480 680 800 650 480 680 800 650 460 670 780 640 460 670 780 640
33 7 47 8 56 2 45.7 33 7 47 8 56 2 46 7 35 3 47 1 54 8 45 0 35 3 47.1 54.8 46 0
930 1250 1420 1200 930 1250 1420 1200 880 1220 1390 1160 880 1220 1390 1160
;610 E 342 9
297.4 302 3 296 7 248 8 297 4 392.3 293 2 297 4 298 1 305 8
%.: 293 2 299 5 2 4 7 282.4
LbsJin.2 Ka.lcm.2 900 63 3 1210 85 1 1500 105 5 1200 84 4 970 68 2 1210 85 1 1500 105 5 1230 86 5 880 61 9 1170 82 3 1420 1160 900 63 3 1170 82 3 1420 99 8 1160 81 5
480 670 850 670 480 670 850 670 440
7 2 6 3 7 2
6
E? !
~
400 %
500%
LbsJin.2 Kg.jcm.2 1600 112.5 2000 140.6 2320 163.1 1970 138.5 1580 111.1 2000 140 6 2290 161 0 1960 137 8 1500 105 5 1950 137 1 2250 138 2 1900 133 6 1580 ld9 7 1900 133 6 2250 158 2 1900 133 6
LbsJin.2 Kg.jcm.2 2470 173.6 2070 208.8 3330 234.1 2920 205,3 2390 168 0 2970 208 8 3300 232 0 2890 203 2 2360 165 9 2900 203 9 3270 229 9 2840 199 7 2380 167 3 2840 199 7 3270 229 9 2830 198 9 173 2oq 230 20d 173 206
158 2 135.0
2470 2940 3280 2900 2470 2940 3280 2900 2400 2980 3280 2890 2400 2980 3300 2890
112 5 139.9 157 5 136 4 112 5 139 9 157 5 136 4 168 3 139 9 164 7 134 3 108 3 137 8 154 7 153.6
2470 3000 3270 2910 2470 3000 3270 2910 2360 2950 3200 2840 2360 2900 3200 2820
173 6 210 9 229.9 204.6 173 6 210 9 228 9 204 6 165.9 207 4 225.0 199.7 165.9 203.9 226.0 198.2
111.1 137.8 137.5 13.5 7 111.1 137.8 137 5 135 7 108 3 138 5 148 2 135.0
? 88 0
1580 1960 2240 1930 1580 1960 2240 1930 1540 1970 2250 1920 1540 1970 2250 1920
65 4 87 9 99 8 84 4 65 4 87 9 99 8 84.4
1600 1990 2240 1940 1600 1990 2240 1940
97 7 81.5 61.9 85 8 97 7
2204;; 1910., 1540 ' 1960 2200 1900
65 4 84 4 100 5 83 7 65 4 84 4 100 5 83 7 6 7 8% 4 9 8 89 0 64 7
600%
6 7 6 9 6 7
E! ; 168 7 209 5 230 6 203 2 168 20Q a 232 0 203 2
3480 3940 4200 3870 3410 3940 4200 3850 3320 3930 4220 3820 3340 3870 4200 3800
244.6 277.0 295.3 272.1 239.7 277.0 295.3 270.7 233.4 276.3 296.7 268.5 234.8 272.1 295.3 267.1
3500 4220 3890 3500 3950 4170 3870 3400 4010
246.1 277.7 296.7 273.5 246.1 277.7 293.2 272.1 239.0 281.9
3850 3400 2010
270:7 239.0 141.3
3950
3840
270:O
3500 3990 4130 3870 3500 3990 4200 3900 3340 3920 4150 3800 3340 3380 4050 3760
246.1 280.5 290.3 272.1 246.1 280.5 295.3 274.2 234.8 275.6 291.7 267.1 234.8 272.8 284.7 264.3
~
35
10
40
70
100 '
30 45 60 Av. 30 45 60 Av. 30 45 60 Av., 30 45 60 Av.
4300 4220 4130 4220 4250 4270 4200 4244 4190 4290 4200 4230 4070 4210 4050 4110
302.3 2 6 7 2x0 3 296 7 298.8 300.2 295.3 298.1 294.6 301.6 295.3 297.4 286.1 296.0 284.7 288.9
2:
81 5
'
I N D UXTRIAL A N D ENGINEERING CHEMISTRY
November, 1928
Table XV-Part
1269
11, Effect of Humidity (Formula 5)
TENSILE AT ELONGATION OF: TEXP. HUYIDITYCURE
Q
C. 15
FINALTENSILE
2005;
400%
LbsJin.2 Kg./cm.2 640 45.0 950 66.8 1310 92.1 970 68.2 780 54.8 990 69 6 1320 92 8 1030 72.4 720 50 6 1020 71 7 1300 91 4 1010 71 0 800 56 2 1080 76 9 1380 97 0 1090 76 6
LbsJin.2 KgJcm.2 1200 84.4 1620 113 9 2180 153 3 1670 117.4 1320 92.8 1710 120 2 2200 154 7 1740 122.3 1300 91 4 1800 126 5 2180 153 3 1760 123 7 1420 99 8 1730 121 6 2200 154 7 1780 125 1
yo
Min.
10
40 60 90 Av. 40 60 90 Bv. 40 60 90 Av. 40 60 90 AI..
3910 4400 4750 4350 3950 4460 4740 4380 3950 4480 4680 4370 4180 4520 4740 4480
274.9 309.3 333.9 305.8 277.7 313.5 333.2 307.9 277.7 314.9 329 0 307 2 293 9 317 8 333 2 314 9
290 480 700 490 370 480 700 520 320 510 680 510 390 550 700 550
20 33 49 34 26 33 49 36 22 35 47 35 27 38 49 38
40 60 90 Av. 40 60 90 Av. 40 60 90 Av. 40 60 90 Av.
3920 4460 4680 4350 4080 4530 4770 4460 4270 4590 4710 4520 4380 4630 4700 ,4570
275 6 313 5 399 0 305 8 286 8 318 5 335 3 313 5 300 2 322 7 331 1 317 8 307.9 325.5 330.4 321.3
300 480 660 480 350 550 660 520 410 580 710 570 490 600 740 610
21 1 33 7 46 4 33.7 24 6 38 7 46 4 36 6 28 8 40 8 49 9 40 1 34.4 42.2 52.0 42.9
680 980 1250 940 770 1080 1250 1030 860 1140 1360 1120 920 1190 1420 1180
40 60 90 Av. 40 60 90 .4v. 40 60 90 Av. 40 60 90 Av.
3820 4480 4740 4350 4040 4620 4700 4450 4350 4710 4670 4580 4610 4800 4520 4640
268.5 314.9 333.2 305.8 284.0 324.8 330.4 312.8 305.8 331.1 328.3 322.0 324.1 337.4 317.8 326.2
300 440 650 460 360 510 710 530 460 600 730 590 560 730 900 730
21.1 30.9 45.7 32.3 25.3 35.9 49 9 37 3 31.6 42.2 51.3 41.5 39.4 51.3 63.3 51.3
690 910 1250 950 770 1050 1320 1080 900 1200 1370 1160 1110 1390 1610 1370
40
70
100
4 7 2 4 0 7 2 6 5 9 8 9 4 7 2 7
500 ' A
300%
600wn
Lbs.iin.2 Kg./cm.2 1980 139.2 2530 177.9 3280 230.6 2560 180.0 2110 148.3 2640 185.6 3300 232.0 2680 188.4 2090 146.9 2700 189.8 3280 230.6 2630 189.1 2280 160.3 2740 192.6 3320 233.4 2780 195.4
LbsJin.2 2840 3560 4320 3570 3070 3690 4350 3700 3060 3720 4320 3710 3280 3760 4430 3823
Kg./cm.? 149.7 250 3 303.7 251.0 215.8 259.4 305.8 260.1 215 1 261 5 305 8 260 8 230 6 244 3 311 4 268 8
~~
25
10
40
70
100
36
10
40
70
100
-
Table XVI-Part
9 9 1 1 9 9 4 5 1 6 7 7 7 8 0
8
1290 1720 2080 1700 1380 1800 2080 1760 1510 1880 2220 1870 1600 1960 2300 1950
90 7 120 9 146 2 119 5 97.0 126 5 146 2 123 0 106.2 133.2 156.1 131.5 112 5 137 8 161 7 137.1
2100 2620 3180 2630 2200 2830 3180 2740 2400 2920 3370 2900 2510 3000 3460 2990
147.6 184.2 223.6 184.9 154.7 198.9 223.6 192.6 168.7 205.3 236.9 203.9 176.5 210.9 243.2 210.2
3020 3700 4280 3670 3130 3840 4320 3760 3430 4020 4480 3080 3540 4130 4500 4060
212.3 260 1 300 9 258 0 220.0 270 0 303.7 264.3 241.1 282.6 314.9 279.8 248.9 290.3 316.4 285.4
48 5 64 0 87 9 66 8 54 1 73 8 92 8 75 9 63 3 84 4 96 3 81 5 78 0 97 7 113.2 96.3
1270 1620 2020 1640 1400 1790 2190 1790 1600 1980 2220 1930 1900 2200 2520 2210
89 3 113 9 142 0 115 3 98 4 125 8 154 0 125 8 112 5 139.2 156.1 135.7 133.6 154.7 177.2 155.4
2020 2520 3120 2550 2180 2780 3280 2750 2510 3090 3380 2970 2880 3310 3690 3290
142.0 177.2 219.3 179.3 163.3 195.4 230.6 193.3 176 5 212 3 237 6 208 8 202 5 232.7 259 4 231 3
2930 3590 4180 3570 3120 3830 4370 3770 3550 4080 4480 4040 3050 4400 4700 4350
206.0 252.4 293.9 251.0 219.3 269.2 307.2 265.0 249.6 286.8 314.9 284.0 277.7 309.3 330.4 305.8
47 68 87 66 54 75 87 72 60 80 95 78 64 83 99 83
11, Effect of H u m i d i t y : Average of Three Cures a n d Three Temperatures
~
HUIIIDITYTEMP.
TENSILE A T ELONGATION
FIXALTEIVSILE 3007,
%
40
OC.
;; 35 Av.
70
loo
70
100
15 25 35 Av. 15 25 35 Av.
15
25 35 Av. 15 25 35 Av.
Lbs./in.' 3840 4030 3920 3930 3890 3910 3730 3840 3820 3830 3690 3780 3950 3740 3670 3790 3670 3860 3790 3770 3750 3780 3690 3740 3720 3630 3630 3660 3680 3580 3550 3600
Kg./cm.2 270 0 283 3 275 6 276 3 273 5 274 9 262 2 270 0 268 5 269 2 259 4 265 7 277 7 262 9 258 0 266 4 258.0 271.4 266 4 265 0 263 6 265 7 259 4 262 9 261 5 255 2 255 2 257 3 258 7 251 7 249 6 253 1
LbsJin.2 Kg./cm.z 170 12.0 170 12.0 170 12.0 170 12.0 170 12 0 170 12 140 9 8 160 11 2 0 170 12 0 140 130 9 8 1 150 10 6 140 100 130
7 0 9 1
160 170 170 170 160 160 170 160 150 150 150 150 150 150 130 140
11 2 12 0 12 0 12 0 11 2 11 2 12 0 11 2 10 5
10 10 10 10
5
5 5 5 10 5 9 1 9 8
1
1
Lbs./in.? Kg./cm.? 310 21.8 340 23.9 320 22.5 320 22.5
%E
:i ii {
300 340 320 320 300 320 310 310 300 290 290 290 290 270 260 270
21 23 22 22 21 22 21 21 21 20 20 20 20 19 18 19
300 310 250 280 280 270 230 260
21 8
19.7 19 7 19 16 2 18 3 0
1 9 5 5 1 5 8 8 1 4 4 4 4 0
3 0
(Continued on next p a g e )
1 1 1
OF:
500 yo
I
4005;
1
6005
Lbs./in.2 Kg./crn.Z 700 49.2 750 52.7 710 49.9 720 50.6 700 49 2 710 49 9 620 43 6 680 47 8 670 47 1 640 45 0 540 38 0 620 43 6 620 43 6 600 42 2 490 34 4 570 40 1 680 750 720 720 650 700 690 680 630 630 620 630 620 590 560 590
*
47 52 50 54 45 49 48 47 44 44 43 44 43 41 39 41
8 7 6 6 7 2 5
8 3 3
6 3 6 5 4 5
Lbs./in.? 1700 1780 1790 1760 1720 1730 1540 1660 1650 1590 1310 1520 1480 1520 1270 1420 1530 1650 1600 1590 1470 1570 1570 1540 1470 1400 1410 1430 1450 1350 1270 1360
&./cm.? 119 5 125 1 123 8 123 7 120 9 121 6 108 3 116 7 116 0 111 8 92 1 106 9 104 0 106 9 89 3 99 8 107 6 116 0 112 5 111 8 103 3 110 4 110 4 108 3 103 3 98 4 99 1 100 5 101 9 94 9 89 3 95 6
1 70056 I Lbs.iin.2 K ~ . / c m . : 3280 3350 3410 3350 3300 3280 3110 3220 3190 3100 2680 2990 2960 2930 2670 2850
230 6 235 5 239 7 235 5 232 0 230 6 218 6 2213 _ 4224 3 217 9 188 4 210 2 208 1 205 3 187 7 200 4
2960 3150 3100 3070 2890 3020 3030 2980 2880 2800 2760 2810 2830 2660 2530 2670
208 221 217 215 203 212 213 209 202 196 194 197 198 187 177 187
1 4 9 8 2 3 0 5 5 8 0 5 9 0 9
7
.
INDUSTRIAL AND ENGINEERING CHEMISTRY
1270 Table XVI-Part HUMIDITY TEMP.
Vol. 20,:No. 11
11, Effect of Humidity: Average of Three Cures and Three Temperatures-(Continued)
TENSILE AT ELONGATION OF:
FINALTENSILE
400% 3
%
OC.
10
15 25 35 Av. 15 25 35 Av. 15 25 35 Av. 15 25 35 Av.
40
70
100
LbsJin.3 KgJcrn.8 3460 243.2 3530 248.2 3420 240.4 3470 243.9 3380 237.6 3530 248.2 3500 246.1 3470 243.9 3580 251.7 3670 258.0 3570 251.0 3610 253.8 3550 249.6 3720 261.5 3640 255 9 3640 255.9
Table XVII-Part
FOR- HuMULA
4
%
OC.
10
15 25 35 Av. 15 25 35 Av. 15 25 35 Av. 15 25 35 Av.
70
100
5
10
40
70
100
15 25 35 Av. 15 25 35 Av. 15 25 35 Av. 15 25 35 Av.
4350 4350 4350 4350 4380 4460 4450 4430 4370 4520 4580 4460 4480 4570 4640 4560
305.8 305.8 305.8 305.8 307.9 313.5 312.8 311.4 307.2 317.8 322.0 313.5 314.9 321.3 326.2 320.6
1
c.
%
15
10 40 70 100 Av. 10 40 70
25
35
2
15
25
Av. loo lo 40 70 100 Av.
10 40 100 70 Av. 10 40 70 100 Av.
300%
Lbs./in.l Kg./cm.l 670 47.1 .. . 630 44:3 650 45.7 650 45.7 670 47.1 630 44.3 650 45.7 650 45.7 610 42 9 620 43.6 640 45.0 620 43.6 610 42.9 620 43.6 640 45.0 620 43.6
3670 3750 3720 3680 3705 3860 3780 3630 3580 3710
258.0 263.6 261.5 258.7 260.5 271.4 265.7 255.2 251.7 260.8
340 350 330 340 340 350 330 340 350 370 370 360 380 430 440 420
23.9 24.6 23.2 23.9 23.9 24.6 23.2 23.9 24.6 26.0 26.0 25.3 26.7 30.2 30.9 29.5
LbsJin.1 730 740 720 730 740 750 760 750 780 810 859 810 870 940 950 920
Kg./cm.l 51.3 52.0 50.6 51.3 52.0 52.7 53.4 52.7 54.8 56.9 59.8 56.9 61.2 66.1 66.8 64.7
LbsJin.2 KgJcm.1 1510 1580 1550 1550 1560 1610 1610 1590 1660 1720 1760 1710 1790 1950 2000 1910
106.2 111.1 109.0 109.0 109.7 113.2 113.2 111.8 116.7 120.9 123.7 120.2 125.8 137.1 140.6 134.3
490 480 460 480 520 520 530 520 510 570 590 560 550 610 730 630
34.4 33.7 32.3 33.7 36.6 36.6 37.3 36.6 35.9 40.1 41.5 39.4 38.7 42.9 51.3 44.3
600%
400%
1200 1190 1200 1200 1230 1190 1200 1210 1160 1180 1160 1170 1160 1180 1160 1170
84.4 83.7 84.4 84.4 86.5 83.7 84.4 85.1 81.5 83.0 81.5 82.3 81.5 83.0 81.5 82.3
970 940 950 950 1030 1030 1080 1050 1010 1120 1160 1100 1090 1180 1370 1210
68.2 66.1 66.8 66.8 72.4 72.4 75.9 73.8 71.0 78.7 81.5 77.3 76.6 83.0 96.3 85.1
11. Effect of TemDerature:
LbsJin.2 Kg./cm.l 1970 138.5 1930 135 7 1940 136.4 1950 137.1 1960 137.8 1930 135.7 1940 136.4 1940 136.4 1900 133.6 1920 135.0 1910 134.3 1910 134.3 1900 133.6 1920 135.0 1900 133.6 1910 134.3 1670 1700 1640 1670 1740 1750 1790 1760 1760 1870 1930 1850 1780 1950 2210 1980
117.4 -119.6 115.3 117.4 122.3 123.0 125.8 123.7 123.7 131.5 135.7 130.1 125.1 137.1 155.4 139.2
2920 2900 2910 2910 2890 2900 2910 2900 2840 2890 2840 2860 2830 2890 2820 2850
205.3 203.9 204.6 204.6 203.2 903.9 204.6 203.9 199.7 203.2 199.7 201.1 198.9 203.2 198.2 200.4
2560 2630 2550 2580 2680 2740 2750 2720 2690 2900 2970 2850 2780 2990 3290 3020
180.0 184.9 179.3 181.4 188.4 192.6 193.3 191.2 189.1 203.9 208.8 200.4 196.4 210.2 231.3 212.3
LbsJin.8 Kg./cm.g 3870 272.1 3890 273.5 3870 272.1 3880 272.8 3850 270.7 3870 272.1 3900 274.2 3870 272.1 3820 268.5 3850 270.7 3800 267.1 3820 268.5 3800 267.1 ' 3840 270.0 3760 264.3 3830 269.2 3570 3670 3570 3600 3700 3760 3770 3740 3710 3980 4040 3910 3823 4060 4350 4080
251.0 258.0 251.0 253.1 260.1 264.3 265.0 262.9 260.8 279.8 284.0 274.9 268.8 285.4 305.8 286.8
Averale of Three Cures
TENSILE AT ELONGATION OF:
FINALTENSILE
Lbs./in.a Kg./cm.a 3840 270.0 3890 273.5 3820 268.5 3950 277.7 3875 272.4 4030 283.3 3910 274.9 3830 269.2 3740 262 9 3880 272.8 3920 275.6 3730 262.2 3690 259.4 258.0 3670 3750 263.6
h a ,Kg./cm-a
TENSILE AT ELONGATION OF:
Table XVIII-Part TEMP. HUMIDITY
Lbs /
Effect of Humidity: Average of Three Cures a n d Three Temperatures
200% Lbs./in.a Kg./cm.a 4260 299.5 4250 298.8 4220 296.7 4240 298.1 4210 296.0 4230 297.4 4240 298.1 4260 299.5 4240 298.1 4260 299.5 4230 297.4 4240 298.1 4250 298.8 4160 292.4 4110 288.9 4170 293.2
600%
Lbs./in.l Kg./cm.l 180 ~ . . 12.7 . 170 12.0 170 12.0 170 12.0 180 12.7 170 12.0 170 12.0 170 12.0 180 12.7 190 13.4 190 13.4 190 13.4 200 14.1 230 16.2 220 15.5 220 15.5
FINALTENSILE
YIDITY
40
1
LbsJin.1 Kg./cm.l 90 6.3 80 5.6 80 5.6 80 5.6 90 6.3 80 5.6 80 5.6 80 5.6 100 7.0 100 7.0 110 7.7 100 7.0 100 7.0 110 7.7 120 8.4 110 7.7
300%
400%
LbsJin.2 Kg./cm.a
LbsJin.1 KgJcm.1 310 21.8 310 21.8 310 21.8 280 19.7 300 21.1 340 23.9 310 21.8 290 20.4 270 19.0 300 21.1 320 22.5 300 21.1 250 17.6 230 16.2 275 19.3
170 170 170 140 160 170 170 140 150 160 170 140 130 100 135
12.0 12.0 12.0 9.8 11.2 12.0 12.0 9.8 10.5 11.2 12.0 9.8 9 1 7.0 9.6
160 160 150 150 155 170 160 150 150 180
11.2 11.2 10.5 10.5 10.9 12.0 11.2 10.5 10.5 11.2
300 300 300 290 300 340 320 290 270 305
600%
21.1 21.1 21.1 20.4 21.1 23.9 22.5 20.4 19.0 21.4
(Continued on next page)
Lbs./in.l Kg./cm.P 700 49.2 700 49.2 670 47.1 620 43.6 670 47.1 750 52.7 710 49.9 640 45.0 600 42.2 675 47.5 710 49.9 620 43.6 540 38.0 490 34.4 590 41.5 680 650 630 620 645 750 700 630 690 670
47.8 45.7 44.3 43.6 45.3 52.7 49.2 44.3 41.5 47.1
Lbs./in.a KgJcrn.2 1700 119.6 1720 120.9 1650 116.0 1480 104.0 1640 115.3 1780 125.1 1730 121.6 1590 111.8 1520 106.9 1655 116.3 1790 126.8 1540 108.3 1310 92.1 1270 89.3 1480 104.0 ~~
1530 1470 1470 1450 1480 1650 1570 1400 1350 1490
107.6 103.3 103.3 101.9 104.0 116.0 110.4 98.4 94.9 104.7
Lbs./in.a Kg./crn.l 3280 230.6 3300 232.0 3190 224.3 2960 208.1 3180 223.6 3350 235.5 3280 230.6 3100 217.9 2920 205.3 3160 222.1 3410 239.7 3110 218.6 2680 188.4 2670 187.7 2970 208.8 2960 2890 2880 2830 2890 3150 3020 2800 2660 2910
208.1 203.2 202.5 198.9 203.2 221.4 212.3 196.8 187.0 204.6
November,
I-VDUSTRIAL A N D ENGINEERING CHEJIISTRY
1928
11, Effect of Temperature:
Table XVIII-Part
Average of Three Cures-(Continued) TENSILE A T ELONGATION OF:
FORYULA TEMP. HUMIDITY F I N A L TENSILE 300% 0
c.
2
35
3
15
% 10 40 70 100
Av.
Lbs /in.? Kg./cm.? 3790 266.4 3690 259.4 3630 255.2 3550 249.6 3665 257.6 3460 3380 3580 3550 3490 3530 3530 3670 3720 3610 3420 3500 3570 3640 3540
10 40 70 100
Av. 25
10 40 70 100
Av. 35
10
1271
243 2 237.6 251.7 249.6 245.3 248.2 248 2 258.0 261.5 253.8 240.4 246.1 251.0 255.9 248.9
600 %
500%
400%
167 167 150 130 150
11.7 11.7 10.5 9.1 10.5
320 310 290 260 295
22.5 21.8 20.4 18.3 20.7
90 90 100 100 95 80 80 100 110 90 80 80 110 120 100
6.3 6.3 7.0 7.0 6.7 5.6 5.6 7.0 7.7 6.3 5.6 5.6 7.7 8.4 7.0
180 180 180 200 185 170 170 190 230 190 170 170 190 220 190
12.7 12.7 12.7 14.1 13.0 12.0 12.0 13.4 16.2 13.4 12.0 12.0 13.4 15.5 13.4
Lbs./in.2 KgJcm.1 720 50 6 690 48.5 620 43.6 560 39.4 650 45.7 340 340 350 380 350 350 350 370 430 375 330 330 370 440 370
1600 1570 1410 1270 1460
112.5 110.4 99.1 89.3 102.6
730 740 780 870 780 740 750 810 940 810 720 760 850 950 820
23.9 23.9 24 6 26.7 24.6 24.6 24.6 26.0 30.2 26.3 23.2 23.2 26.0 30.9 26.0
700%
LbsJin.2 Kg./cm.t 3100 217.9 3030 213.0 2760 194.0 2530 177.9 2855 200.7
51 3 52.0 54.8 61 2 54.8 52.0 52.7 56 9 66 1 56.9 50.6 53.4 59.8 66.8 57.6
1510 1560 1660 1790 1630 1580 1610 1720 1950 1715 1550 1610 1760 2000 1730
106.2 109.7 116.7 125.8 114.6 111.1 113.2 120.9 137.1 120.6 109.0 113.2 123.7 140.6 121.6
* Table XIX-Part FOBMULA
HU-
TEMP.MIDITY
OC.
%
15
10 40 70 100
4
Av. 25
10 40 70 100
Av. 35
10 40 70 100
Av.
11, Effect of Temperature:
Average of Three Cures
TENSILE AT ELONGATION OF: FINALTENSILE
I
200%
I
400%
300%
LbsJin.2
Lbs./in.Z Kg./cm.: 4260 299.5 4210 296.0 4240 298.1 4250 298.8 4265 299.8 4250 298.8 4230 297.4 4260 299.5 4160 292.4 4225 297.0 4220 296.7 4240 298.1 4230 297.4 4110 288.9 4200 295.3
670 670 610 610 640
47.1 47.1 42.9 42.9 45.0 44.3 44.3 43.6 43.6 43.9 45.7 45.7 45.0 45.0 45.3
1200 1230 1160 1160 1190 1190 1190 1180 1180 1185 1200 1200 1160 1160 1180
84.4 86.5 81.5 81.5 83.7 83.7 83.7 83.0 83.0 83.3 84.4 84.4 81.5 81.5 83.0
1970 1960 1900 1900 1930 1930 1930 1920 1920 1925 1940 1940 1910 1900 1920
Kg./cm.z 138.5 137.8 133.6 133.6 135.7 135.7 135.7 135.0 136.0 135.3 136.4 136.4 134.3 133.6 13ii.O
490 520 510 550 520 480 520 570 610 545 460 530 590 730 580
34.4 36.6 35.9 38.7 36.6 33.7 36.6 40.1 42.9 38.3 32.3 37.3 41.5 51.3 40.8
970 1030 1010 1090 1025 940 1030 1120 1180 1070 950 1080 1160 1370 1140
68.2 72.4 71.0 76.6 72.1 66.1 72.4 78.7 83.0 75.2 66.8 75.9 81.5 96.3 80.1
1670 1740 1760 1780 1740 1700 1750 1870 1950 1820 1640 1790 1930 2210 1890
117.4 122.3 123.7 125.1 122.3 119.5 123.0 131.5 137.1 127.9 115.3 125.8 135.7 155.4 132.9
500%
1 LbsJin.2 2920 2890 2840
Kg./cm.a 205.3 203.2 199.7
2560 2680 2690
180.0 188.4 189.1
2630 2740 2900 2990 2815 2550 2750 2970 3290 2890
184.9 192.6 203.9 210.2 197.9 179.3 193.3 208.8 231.3 203.2
I
I
600%
Lbs./in.2 3870 3850 3820 3800 3830 3890 3870 3850 3840 3860 3870 3900 3800 3760 3832
Kg./cm.? 272.1 270.7 268.5 267.1 269.2 273.5 272.1 270.7 270.0 271.4 272.1 274.2 267.1 264.3 269.4
~
5
15
10 40 70 100
Av. 25
10 40 70 100
Av. 35
10 40 70 100
Av.
-
4350 4380 4370 4480 4395 4350 4460 4520 4570 4475 4350 4450 4580 4640 4505
305.8 307.9 307.2 314.9 309.0 305.8 313.5 317.8 321.3 314.6 305.8 312.8 322.0 326.2 316.7
Table XX-Part 11, Effect of Humidity: 12-Day Exposure. of Three Cures a n d Three Temperatures FORMULA HUMIDITY FINALTENSILES 70
1
t
3
4
5
10 40 70 100 10 40 70 100 10 40 70 100 10 40 70 100 10 40 70 100
LbsJin.2 3653 3779 3619 3486 3703 3632 3536 3465 3434 3381 3481 3554 4263 4227 4200 4120 4340 4532 4640 4652
Kg./cm.l 256.8 265.7 254.4 245.1 260.3 255.3 248.6 243.6 241.4 237.7 244.7 249.8 299.7 297.2 295.3 289.6 305.1 318.6 326.2 327.0
'
251.0 260.1 260.8 268.8 260.1 258.0 264.3 279.8 285.4 272.1 251.0 265.0 284.0 305.8 276.3
Average
MODULI LbsJin.2 732 697 624 551 711 666 604 550 368 382 447 476 1913 1900 1878 1889 1674 1837 2036 2270
3570 3700 3710 3823 3700 3670 3760 3980 4060 3870 3570 3770 4040 4350 3930
Kg./cm.2 51.5 49.0 43.9 38.7 50.0 46.8 42.5 38.7 25.9 26.9 31.4 33.5 134.5 133.6 132.0 132.8
Table XXI-Part 11, Effect of Temperature: 12-Day Exposure, Average of Three Cures a n d Four Humidities FORMULA TEXP
c. 1
2 3 4 3
15 25 35 15 25 35 16 25 35 15 25 35 15 25 35
FINALTENSILE Lbs./in.z 3757 3694 3451 3660 3610 3455 3545 3465 3380 4305 4190 4110 4550 4590 4510
Kg./cm.2 264.1 259.7 242.6 257.3 253.8 242.9 249.2 243.6 237.6 302.6 294.6 288.9 319.9 322.7 317.1
.
MODULI
677 679 57 1 640 660 610 410 420 420 1940 1905 1840 1910 1995 1955
47.6 47.7 40.1 45.0 45.7 42.9 28.8 29.5 29.5 136.4 133.9 129.4 134.3 140.2 137.4
1272
INDUSTRIAL AND ENGINEERING CHEMISTRY
Table XXII-Effect BEFOREVULCANIZATIOX
6 24 24 24'/2 24 24 25 24 24 26 24 24 30 24 48 48 48 481/2 48 48 49 48 48 50 48 48 54 48 6 24 24 24'/2 24 24 25 24 24 26 24 24 30 24 48 48 48 481/2 48 48 49 48 48 50 48 48 54 48 5
a
6 24 24 24Vr 24 24 25 24 24 26 24 24 30 24 48 48 48 48'/t 48 48 49 48 48 50 46 48 54 $8
Hours
82" F.
% 0.061 0.120
1/2
1
1
2
2
6
0,120 6
0.310 0.150
'/2 '/2
1
1
2 6
2 6
0.130 0.120 0.170 0.360 0 048 0 074
'/2 '/2
1
1
2
2
6
0.028 6
0.110 0.075
'/2
1 2 6
1/2
1 2 0 056
6
0.120
0 032 0.068 :/a
1 2
'/2
1 9
6
0.055 6
0.141 0.094
1/2
1 2
'/a
1 0.082 2
0.150 0.068
6
0.187
6
TENSILE AT ELONGATION OF:
FINALTENSIL
Hour
1/2
of Humidity
BEFORE
ExExExposure posiire posurr 55% n t 10% a t 100% a 8 2 ° F . 82'F. 82OF.
Hours
Vol. 20, No. 11
mperatiire changed during cure.
Hours
500% Modulu
600% Modulu!
700?& Modulus
Lhr./ zn.2 780 750 740 700 7.50 790 760 700 770 770 750 730 750 700 740 760 790
Lbs./
cm. 54 8 54 8 52 0 49 2 52 7 55 5 53 4 53 4 54 1 54 1 52 7 52 7 52 7 49 2 52 0 53 4 55 5
1580 1560 1580 1630 1640 1640 1500 I590 1560 1600 1580 1480 1600 la00 1600
115.3 112.5 111.1 109,7 111.1 114.6 115.3 115.3 111.8 111.8 109 7 112.5 111.1 104.0 112.5 112.5 112.5
Absi/ rn. 3060 3000 3080 3010 3060 3100 3100 3100 3040 3040 2970 3000 3040 2880 2920 3140 3000
cm. 215 1 210 9 216 5 211 6 215 1 217 9 217 9 217 9 213 7 213 7 208 8 210 9 213 7 202 5 205 3 220 7 210 9
Lbs./ in.2 3990 3900 4000 3940 3'100 3730 3840 3840 4030 3880 3810 3930 3900 3880 3950 4010 3800
cm. 280 , 274 : 281 : 277 I 274 j 262 270 I 270 I 283 : 272 I 207 I 276 : 274 ' 272 277 , 281 < 267. I
3900 3800 3900 3900 3860 3950 3760 3900 3920 3880
274 Z 267 1 274 Z 274 Z 271 4 277 i 264 2 274 2 275 e 272. S
770 770 770 770 750 750 780 720 720 700
54.1 54.1 54.1 54.1 52 7 52.7 54.8 50.6 50.6 49.2
1580 1580 1580 1380 1550 1550 1640 1540 1570 1450
111.1 111.1 111.1 111.1 109.0 109.0 115.3 1n8.3 110.4 101.9
3000 3000 3000 3000 2990 2990 3020 29.50 3000 2830
210 210 210 210 210 210 212 207 210 198
72 72 72 72 72 72 72 72 72 72 72 72 72 72 24 72 72 72 72 72 72 72 72 72 72 72 72 72
3120 3090 3080 2700 2970 3100 3010 3080 2900 2780 3270 3180 3110 2980 2620 2680 3110 1950 !900 2760 3080 1190 KO 1200 ingo !880 !900
219 3 217 2 216 5 189 8 208 8 217 9 211 6 216 5 203 9 195 4 229 9 223 6 218 6 209 5 184 2 188 4 218 6 217 2 207 4 203 9 194 0 216 5 224 3 205 3 225 0 217.2 202.5 203.9
410 410 400 400 370 400 400 4no 380 340 420 400 400 400 400 380 420 400 400 360 360 370 370 400 400 350 3.50 390
28 8 28.8 28 1 28.1 26.0 28 1 28.1 28.1 26.7 23 9 29.5 28.1 28.1 28.1 28.1 26.7 29.5 28.1 28.1 25.3 25.3 24.0 26.0 28.1 28.1 24 6 24.6 27.4
810 790 760 760 700 800 8no 800 730 700 800 790 770 770 750 700 820 800
56.9 55.5 53.4 53.4 49.2 56.2 56.2 56.2 51.3 49.2 56.2 55.5 54 1 54.1 52.7 49.2 57.6 56.2 56.2
1630 1580 1500 1530 1420 1600 1570 1560 1480 1410 1650 1600 1490 1520 1480 1400 1640 1600 1600 1480 1400 1490 1510 1550 1620 1450 1440 1600
114.6 111 1 105 5 107.6 99 8 112 5 110.4 109 7 104.0 99.1 116 0 112.5 104.7 106.9 104.0 98.4 115.3 112.5 112.5 104.0 98.4 104.7 106.2 109.0 113.9 101.9 101.2 112.5
48 48 48 48 48 48 48 48 48 48 48 48 48 48 24 48 48 48 48 48 48 48 48 48 48 48 48 48
1360 1360 1370 1.770 1310. a10 320 400
306 5 306 5 307 2 307.2 303.0 303 n 3n3 7 309.3
400 320 450 230 370
309.3 303.7 312.8 297 4 307.2 317.8 317 8 319.9 314.9 312 1 312.8 313.5 314.2 309 3
48 48 48 48 48 48 48 48 48 48 48 48 48 = 48 24 48 48 48 48 48 48 48 48 48 48 48 48 48
3mo
520
*
520 550 480 410 450 460 470 400 310 480 450
K
