HIGHER PARAFFIN HYDROCARBONS
TABLE VII. SUMMARY OF PROPERTIES RATEDFOR TYPEOF IMPROVED WOOD^ Impregnsted Property Process Simplicity and uniformity of production 3 Ease of compression 2 Dimensional stability Water 1 Heat I&paot strength 3 Tensile and compressive strength 2 moduli of rupture and of elasticit; in bending Bhearing stress parallel t o grain Perpendicular to laminations 2 Parallel t o laminations 1 Machinability, glueability, paintability 3 Surface appearance 1
FilmBonding Process 1 3
GlueSpreading Process
3
2
1 1
2 36
1 1 1 3
3 1 2 2
2
1b 2
Correlation of Physical Proneerties
a 1 = best: 2 = intermediate. 3 = poorest. b If a less alkaline resin were usLd t h e ease of com ression might have been somewhat less, b u t the, comqressive’strength, mod& of rupture in,bending, a n d modulus of elasticity might have been appreciably higher &s is indicated by d a t a from other sources.
ALFRED W. FRANCIS Socony-Vacuum Oil Company, Inc., Paulsboro, N. J.
differences in physical properties of high-density wood are influenced more by the type of resin and the method than by the particular resin in a group, provided the resin has been properly formulated. An extensive bibliography is available on many of the properties discussed (7, 8, 9, 12). The processes of applying resin to wood have been studied by several of the companies manufacturing resins and to some extent by the Forest Products Laboratory (6, 14). The conditions of bonding time and temperature are important, and should be considered in respect to their influence on final properties, Table VI1 indicates that the choice of material will depend entirely upon its intended use. If high water resistance is required, material 1 is preferable. If lox cost or high strength is desired, 2 or 3 will be preferred. The advantages that appear to be present with the film bonding process are due to its lower resin content. Inherently wood is an exceedingly strong material so that the more we can let the wood character predominate, the more woodlike and the less resinlike will be the finished article. Which process is used depends on the many factors of strength requirement, surface appearance, cost, simplicity of manufacture, and others. The fields of application for material of this type include airplane and ship propellers, bearing plates, jigs, rollers, gears, gun stocks, sporting goods, table tops, heavy-duty flooring, etc.
The observed densities and refractive indices of paraffin hydrocarbons above C11 are correlated. Eighty-three of the hydrocarbons fall into five classes according to structure. Their properties are calculated by functions of the form, A - ( B / n ) , where n is the number of carbon atoms. The same properties of the other forty-seven observed paraffins are calculated by adding increments depending upon the mode of building their structures from those of lower known paraffins. About 10% of the experimental values are so discordant with the calculations as to suggest inaccuracies in the observations. The average discrepancy for the others is +0.0009. The thirty-two observed normal boiling points of branched-chain paraffins above C1, are correlated by similar methods but show poorer agreement, perhaps because of casual observations or inadequate stem corrections. The average discrepancy is +6.4’ C.
T
WO previous papers (8, 9) presented calculations of the physical properties of all paraffin hydrocarbons up to undecanes, which practically covers the gasoline range. Experimental data (6, 6, 7 , 27) are now available for a considerable number of higher paraffins. Kurts and Lipkin ( 2 1 ) made calculations for “average paraffins” in this range, on the basis of molecular volumes, but did not consider individual isomers in det’ail. This paper extends the met,hods used previously (8, 9) to all those paraffin isomers above undecanes whose observed densities, refractive indices, or normal boiling points have been recorded in the literature. This furnishes a possible means of appraising the accuracy of the observations. Values showing substantial discrepancies (more than 0.0050 in density, 0.0030 in index, or 6 ” c. in boiling point) are marked in the tables with question marks. Most of the observations selected are those listed in the two compilations ( 6 , 7) or averages when two or more are given. Original references were examined in most cases, but are shown in the tables only if they are omitted from both compilations because of too recent publication or, in a few cases, because of slight inaccuracies in the quoted data. Some of the paraffins have melting points above 20’ C. so that their densities and refractive indices as liquids can be observed only at higher temperatures. The observation a t the temperature nearest to 20” C., especially by the same observer, is generally selected as being less likely to contain an error due t o temperature. Temperature corrections are applied to the observations according to equations from the former paper (8):
LITERATURE CITED
(1) A r m y Air F o r c e , Specification 15,065, Mat6riel C e n t e r , W r i g h t Field, D a y t o n , 1942.
(2) Anonymous, Plastics ( L o n d o n ) , 1, 166-8 (1937). (3) B e r n h a r d , R. K., P e r r y , T. D . , a n d Stern, E. G., Mech. Eng., 62, 189-95 (1940).
(4) Brnjaikoff, B. J., Ind. Chemist, 6, 502 (1930). ( 5 ) C a m p r e d o n , J., Gdnie civil, 98, 426 (1931). (6) Casselman, R., meeting of Am. SOC.of Mech. Engrs., April, 1943. (7) Delmonte, J., Machine Design, 14, 53-57 (1942). (8) Finlayson, M . , Trans. Am. SOC.M e c h . Engrs., 6 5 , 193-9 (1943). (9) Jervis, A. E. L., Plastics ( L o n d o n ) , 7 , 122-7 (1943). (10) M e r r i t t , R . W,, and W h i t e , A. A , ISD.E N Q .CHEM., 3 5 , 297-301 (1943). (11) P e r r y , T. D . , “ M o d e r n P l y w o o d ” , p p , 195-213, New York, P i t m a n P u b . C o r p . , 1942. (12) Shishkov, V. P., J . A p p l i e d Chem. (U.S.S.R.), 8 , 1043 (1935). (13) Slaght, E. J., Miller, N., a n d Bailey, S. D., “ H i g h D e n s i t y Wood”, P a r t s I to V I I , u n p u b . repts. of Resinous P r o d u c t s a n d Chemical Co., 1941-43. (14) S t a m m , A. J., a n d Seborg, R. M., Trans. Am. Inst. Chem. Engm., 37, 385-98 (1941). (15) S t a m m , A. J., a n d Seborg, R. M . , IND. ENG.CHEM.,28, 1164-9 (1936). (16) S t a m m , A . J., a n d Seborg, R. M., “ T h e Compression of Wood”, mimeograph, Forest P r o d u c t s L a b . , 1941.
dd4/dt = 0.0319(1.13 - d;’) d n ~ l d t = 0.0011(1.13 - d:’)
PRESENTED before t h e Division of Paint, Varnish, and Plastics Chemistly a t CHEMICAL SOCIDTY, Pittsburgh, Pa. the 106th Meeting of t h e AMERICAN
256
INDUSTRIAL AND ENGINEERING CHEMISTRY
March, 1944
257
Footnotes to Table I .
TABLE I. DBNSITIESAND REFRACTIVE INDICES PARAFFIN
HYDROCARBONSt
- 1.17/n*
--
d i 0 = 0.8468 -CalculateddO : t 0.7298 20 0.7404 20 0.7493 20 0.7568 20
Obsvd. d', dk 0.7298 0.7300 0.7404 0.7403 0.7493 0.7488 0.7568 0.7568
15
16 17
0.7632 0.7688 0.7737 0.7780
20 20 20 22
0.7632 0.7688 0.7737 0.7767
18 19 20 21
0.7818 0.7852 0.7883 0.7911
28 32 36.4 40.4
22 23 24 25
OF
naDo = 1.4736
t Standard deviations
NORMAL
rpfraPt,ive -for . .. __- -- ._. - index._.
Calculated-
a
b
Obsvd.
dD
dD
t
1.4116 1.4172 1.4219 1.4259
20 20 20 20
1.4116 1.4172 1.4219 1.4259
1.4119 1.4173 1.4216 1.4266 (18)
0.7636 0.7689 0.7734 0.7767
1.4293 1.4323 1.4348 1.4371
20 22 20 25
1.4293 1.4315 1.4348 1.4352
1.4296 (14) 1.4318(8) 1.4345 1.4356(18)
0.7765 0.7767 0.7773 0.7777 0.7777 0.7778 0.7780 0.7782
1.4392 1.4410 1.4426 1.4441
28 36 46.8 45
1.4361 1.4349 1.4325 1.4348
1.4363 1.4340 1.4325 1.4352 (10)
0.7936 0.7959 0.7981 0.8000
44.4 0.7780 0.7797 0.7778 47.4 0.7785 51.1 0,7785 0.7786 53.9 (10) 0.7787 0 7785
1.4454 1.4466 1.4477 1 4488
46.7 49 65 65
1.4355 1.43614 1.4353" 1.4360 1.4313 1.4303 1.4325 1.4320
26 27 28 29 30 31 32 33
0.8018 0.8035 0.8050 0.8065 0.8078 0.8091 0.8102 0.8113
60.0 (18) 59.4(IO) 61.6 63.8 65.5(10) 68.4 69.8(10) 71.8
0.7780 0.7789 0.7792 0.7797 0.7797 0.7799 0.7798 0.7801
1.4498 1.4506 1.4515 1.4522 1.4529 1.4536 1.4542 1.4548
65 65 65 70 70 70 84
60
1.4354 1.4357 (18) 1.4345 1.4345 1.4354 1.4354 1.4362 1.4364 1.4352 1.4352(19) 1.4360 1.4356 1.4366 1:4324 1.4364 1.4323
34 35 36 37
0.8124 0.8134 0.8143 0.8152
0.7804 0.7806 0.7809 0.7813 0.7807 0.7819 0.7674 0.7682
1.4554 1.4559 1.4564 1.4568
84 84 77 84
1.4331 1.4336 1.4366 1.4346
14
38 39 40 41 42 43 50
0.8160 0.8168 0.8175 0.8183 0.8189 0.8196 0.8234 6 2 b 0.8279
73 74 76 100 100 84 84 84 84 84 93 115 4
(10)
0.7769 0.7791 0.7793 0.7796 0.7799 0.7796 0.7800 0.7800
0.7683 0.7787 0.7795 0.7804 0.7811 0.7819 0.7809 0 7732
0.7688 1.4573 90 0.7771 1.4577 84 0.7785 1.4581 84 84 0.7784 1.4585 0.7803 1.4588 84 0.7810 84 0.79407 1.4592 1.4612 93 0.74657 1 4 6 3 6 120
carbon atoms. Assuming n~ is 0.0020 higher than nna. The original article [Schenck and Kintzinger, Reo. trav. c h i n . . 42, 763 (1923)l and both compilations (6, 7) call this paraffin CsoHizz; but i t must be CszHizs since i t is made from myricyl iodide, and Gascsrd's proof [Corn t. Tend., 170,s 86 (1920)] t h a t the myripyl radical contains 31 cargon atoms is generally accepted. The density determination a t 115.4O C. is extremely low. but those a t higher temperature show an expansion coefficient mdch lower than for any hydrocarbon (dd/dt = 0.00035 compared with a minimum of 0.00057) so ;hat a t the highest temperature, 190.6' C., the observation is near that calculated. This behavior auggesta the presence and gradual elimination of air bubbles.
- 0.62/n*
ng0
n* 10 11 12 13
servations of Cosby, Sutherland, and Whitmore (6) who furnish nwrly half ofthematerial for Table 11. ETHYLPARAFFINS.Similarly, equations are derived and presented in Table I11 for ethyl derivatives, EtCHR2. As for the CHRs class the position of the ethyl group in the molecule is assumed to have no effect upon the properties. This assumption is probably not quite accurate but is supported by previous calculations (9). I n this case there are no reliable data to test the effect. The equations differ from those of Table I1 by a constant increment because the only difference in building up the molecule would be the omission of mode 2. The ratios for that mode are only slightly less than unity. The concordance of this and later tables is inferior to that of Tables I and I1 because the molecular structures are more diversified and the data are obtained from only one investigation in most cases. 2,2'-DIMETHYL PARAFFINS. Table IV presents observations on the 2,2'-dimethyl paraffins, and includes five paraffins with additional isolated methyl groups (no two branches on adjacent carbon atoms). Their properties are corrected simply by the addition of 0.0012 in density
1.4329 1.4334 1.4359 1.4345
1.4331 1.4326 1.4357 1.4358 1.4361 1.4363 1.4365 1.4366 1.4569 1.4373 1.4366 1.4304
1.4375 1.4378 ....
....
DENSITY AND REFRACTIVE INDEX
The densities and refractive indices of the normal paraffins are .correlated in Table I by equations which are simpler than those used previously (8)because the members up t o nonanes are omitted. Since most of the higher normal paraffins are solids, the temperature corrections are applied upward to the temperatures of observation. I n the other tables it is more convenient to reduce all observations to 20" C. The average discrepancy in Table I is *0.0004 in density (omitting the last two observations) and *0.0003 in refractive index. CHRa PARAFFINS. Twenty-seven of the observed paraffins belong to the class CH%, where the R's (not necessarily the same) are normal alkyl groups longer than ethyl. Their properties could be calculated by adding increments for each additional carbon atom, as in the preceding paper (9). But since these paraffins are all linear (mode 1) homologs of 4-n-propylheptane, i t is preferable to take advantage of this uniformity and derive simple equations for their properties from the observed data! as presented in Table 11. The equations imply a ratio of 0.95 for mode 1 when applied todhree alkyl groups, as compared with unity for normal paraffins. The equations neglect the difference between isomers of this class, which is slight, as illustrated by the six hexacosanes. However, an isomer with the branch near the end of a long chain seems to have properties slightly higher than the others. The three hydrocarbons with serious discreuancies (indicated by question marks) all have short branches attached to the middle of a long chain. If the other method of calculation mentioned above were used in these cases, the calculated values would be increased; this increase, however, would be only about 0.0015 in density and 0.0008 in index, not nearly enough to agree with the observations' The average discrepancies and standard tions for the other members are each only 0.0001 greater than in Table I. The good agreement is due in part to the excellent ob-'
for this table: 0.0006 f o r density, 0.0004
* Where n is the number of
TABLE11. DENSITIESAND REFRACTIVE INDICES OF CHRd
PARAFFINS?
-
d:'
Paraffin
ty
~:;:~;;;g~h;f~;~ 12 5-n-Propylnonane l3 4-n-Propy1decane
i15: ~:;:~;~;$;;$~;ane 5-n'Ptopyldodecane
l5 6~n-Propy1dodecane
18 22 24 25
8-n-Propyl~entadecane(18) 4-n-Propylnonadecane 5-n-Butyleicosane 9-n-0cty1heptadecane
g;
$!;:$e:Ji+;:Eane 28 7-n-Hexyldocosane 28 g-n-Octylelcosane
i:31
~~;:~~;;~';~~ane 11-n-Decylheneicosane 32 ll-n-Decyidocosane
$2
:
,
'
:
~
~
=
- 0% 58
Obsvd. 0,7364 0.7465Q 0.7550b 0.7610b
Calcd. 1.41.43 1.4196 1.4240 1.4277
Obsvd. 1.4150 1.4200a 1.4233b 1.4273,
0.7618 0.7679 0.7732 0.7732 0.7855 0.7968 0,8009 0 8028
0.7624b 0.7666 0.7746 0.7720b 0.7911? 0.7968 0.8012 0 8017
1.4277 1.4309 1.4336 1.4366 1 4401 1 4459 1.4481 1.4491
1.4267b 1.4309 1 4333 1.4327b 1 44441 1 4463b 1.4472C 1 4487
0.8057 0.8040 0.8045 0.8041 0.8045 0.8046 0.8045 0 8038 0.8045 0.8040 0.8076 0.8078 0.8076 0.8074 0.8076 0.8076b 0.8102 0.8112 0.8114 0.8115 0.8125 Q.8127
1.4500 1.4500 1.4500 1 4500 1.4500 1.4500 1.4516 1 4516 14516 1.4530 1.4536 1.4542
1 4503 1.4499 1 4498 1.4500 1.4497 1.4497 1 4517 1 4515 1.45026 1.4537 1,4540 14543
::$~ ~
38 18-n-Propylpentatriacontane 0.8180 47 16*n-Pentadecy1dotriaoontane 0.8236
t Standard deviatlons
1.4723
Calcd. 0,7362 0 7463 0.7547 0.7618
8045 g: ~;+~$$C$W;;;;;00.8045 26 9-n-Butyldocosane 26 ll-n-Butyldocosane
,go
- '$
0.8472
for this table:
~o 8270?b , !1.2~Ek;4570 ~1 4608?b ~ &
~
~
'. '.
~
~
4600
~
~
4603b
0.0007 for denslty, 0.0005 for re-
f r a ~ ~ ~ $previously $ ~ (9). b Corrected t o 209 c. This observed refractive index is not gwen in either compllatlon (6, 7), nor in any avallable abstract, but is deduced readily from the observed M Y ,112.92 (Landa, Eech, and Slfva, Chem. Zentr., i933,11, 1332).
~
~
INDUSTRIAL AND ENGINEERING CHEMISTRY
258
Vol. 36, No. 3 ~~
TABLE IV.
DENSITIESAND REFRACTIVE INDICES OF 2,2'-DIMETHYL
-1.24
-
PARAFFINS
di0 0.8468 -
n;O
1.4731 Calcd.
- O.65
Paraffin Calcd. Obsvd. 2,6-Dimethylheptane 0.7090 0.7089 1.4009 2,7-Dimethyloctane 0.7228 0.7226 1.4081 2,Q-Dimethyldecane 0.7435 0 . 7 4 9 v 1.4189 2 10-Dimeth lundecane 0,7515 0.7633? 1.4231 2:5.9-Trimedyldecane 1.423Rb 0.7526b 0.7688? 2,ll-Dimethyldodecane 0.7582 0.76917 1.4267 2,6,11-Trimethyldodecane 0.7653b . . . . 1,43026 2,6.11 15-Tetramethylhexadec;ne (crocetane) 0.7872b 0.7885; 1.44146 22 2.19-Dimethyleicosane 0.7904 0.7950 1.4436 30 2,6,10,15,19,23-Hexamethyltetracosane (squalane) 0.8103b 0.8098 1.4630b 40 2,6,10,14,19,23,27,3l-Octameth yldotriaoontane 0.8230b 0.8228C 1,45921, a Calculated previously (6,7 ) . b Increment added for each additional methyl group. C Corrected to ZOO C. n
9 10 12 13 13 14 15 20
.85
TABLE V. DENSITIES AND
0
REFR.4CTIVE PARIFFIX3
n20
D
-
t2
Figure 1.
16
20C A R B OIN A T O M28S
32
36
40
Degree of Correlation of Observations with Density Equations
and 0.0004 in refractive index for each additional methyl group to the values calculated by the equation. These increments are derived later. Three of the density values and two for refractive index in Table IV are very discordant. R2CHCHRs PARAFFINS. Paraffins with two adjacent branches (except dimethyl derivatives) are given in Table V. Calculations for these hydrocarbons by the method of the second paper (9) would give somewhat higher values for the properties. It seems probable that modes 3c, 4b,and 6b should be subdivided, and that the subdivisions pertinent to this class should have lower ratios. But the empirical method of Table V covers these paraffins more simply and satisfactorily'.
T A B L11 ~1. DENSITIES AiVD REFR.4GTIVE I N D I C E S MONOETHYL PARAFFINS di0 .go
-
0.8493 n
9 9
10 11 11 11 12 12 13 16 20 26
33 37 a
l.42+1? 1.43001C 1.4277: 1,4306 1.441ZC 1,443as0 1,4535 1.458%
'
Calcd. 1.4193 1.4280 1.4342 1.4366 1.4424 1.4424 1.4513
-
-
- '2 Obsvd. 1.4200 1.4279 1.4342" 1.4353a 1.4397 1.4421 1.4517
I D E NS ITY
.82
1.4713
Paraffin Calcd. Obsvd. 3,4-Diethylhexane 0.7484 0.7514 4,5-Diethyloctane 0.7647 0.7632 4 5-Di-n-prop loctane 0.7765 0.7769" 6:Methyl-7-etXyldodecane 0.7812 0.7782" 7,s-Diethyltetradecane 0.7920 0.7871 18 5,6-Di-n-butyldecane 0.7920 0.7911 26 Il-(3-Pentyl-)heneicosane 0.8087 0.8092 32 7,12-Dimethyl-9,1O-di-n-hexyloctadecane 0.8182b 0.8182 a Correctpd t o 20" C. b Increment added for two additional methyl groups. n
.
IKDICES O F RzCHCHRz
dzo = 0.8464 0.98
10 12 14 15 18
ObFd. 1.4008 1.4082
Paraffin 3-Ethylheptane 4-Eth lhe tane 3- andl4-Z%hyloctanes 3-Ethylnonane 4-Ethylnonane 5-Ethylnonane 3-Ethyldeoane 1 7 ) 5-Ethyldecane (80) 4-Ethylundecane 3-Ethyltetradecane 3-Ethyloctadecane 3-Ethyltetracosane (18) 16-Ethylhentriacontane 18-Ethylpentatriacontane Calculated previously (9).
- 1.11
1.4734
Calcd. Obsvd. Calcd. 0.7260 0.7266 1.4090 0.7260 0.7258" 1.4090 0.7383 0.7380a 1.4154 0.7484 0.7484" 1.4207 0.7484 0.7470 1.4207 0.7484 0.7507b 1.4207 0.7568 0.75198 1.4251 0.7568 0.7560 1.4251 0.7639 0.7628 1.4288 0.7799 0.77916 1.4371 0.7938 0.7941 1.4444 0.8066 0.80696 1.4511 0.8157 1.4558 0.82291b 0,.8193 0.820b 1.4577 b Corrected to 20' C.
OF
- oG Obsvd. 1.4090 1.4092" 1.4154" 1.4205a 1.4203" 1.4207b 1.4228b 1.4251 1.4270 1.43706 1.4445b 1.4507b 1.45937'~ 1.45876
1.45596
1.46071
Combining the equations of Tables I to V for density with those for refractive index, respectively, gives as a mean the following general equation for "refractivity intercept" (I@, which is not quite independent of the number of carbon atoms: nI,O
- 0.5 dZo =
1.049 - (0.03/n)
With accurate observations this equation seems to hold within 0.0015 for practically all paraffins. CORRELATION
The degree of correlation of the observations with the equations for density in Tables I to V is illustrated in Figure l. The ordinates are obtained by adding the reciprocal of the number of carbon atoms to the density (corrected to 20" (2.). The purpose of this is to flatten out the curves so as to permit a much larger scale than would be possible if density alone were plotted. This allows more separation of the curves, although it also exaggerates the discrepancies. The curves are plots of the equations in the tables. That for the RzCHCHRt series slopes slightly domward merely because the second constant of its equation is slightly less than unity. The highly cbrved line for the 2,2'-dimethyl series is preferred to a straight horizontal line, which might include three discrepant values (for CIS,CM,and C22) because the observations on the nonane and decane are much more reliable than those mentioned. The slight discrepancy in density for the normal paraffins CI0 to Cns(all observed in the same investigation) is probably not due 1 The calculated properties shown in the previous paper (9)for hydrocarbons of this class, numbers 34, 56, 59,97, 101, 103, 123 (and perhaps 121). and the corresponding undecanes should be revised by the following decremente: C8 co ClO C11 Density, 2 4 6 8 x 10-1 Refractive index 1 2 3 4 x 10-1
Probably the computed boiling points also for these paraffins should be decreased by an equivalent correction (8)-namely, (n 7)" C.
-
INDUSTRIAL AND ENGINEERING CHEMISTRY
March, 1944
to the equation or to the temperature correction, because the three preceding values are a trifle high. Nor is it due to impurities in the samples, because the observations on refractive index on the same samples are also slightly high. It is probably due t o inaccurate temperature or other factor in the density determinations. Refractive index could be plotted similarly, but the relations of curves and extent of discrepancies are substantially the same as for density, as shown in the tables.
259
same manner as for similar hydrocarbons in Tables IV and V.) The increments for mode 3c are those for Clr to CISin Table I, multiplied by 1.94, the ratio for mode 3c at (318. Those for modes 2, 1, and 4a are derived similarly, the last being employed four times:
c-c-c-c-c-c-c-c-c-c-c-c I I I C C4a
I
C0a
I
I
G o
PROPERTIES O F HIGHER PARAFFINS
x
The properties of dodecanes are compared in Table VI. The calculated values (except those from preceding tables) are averages of the ones obtained by former methods frdn all of their precursor undecanes as given in Table V I of the previous paper (9). The different modes are listed in each case. In forming the molecules of still higher paraffins, mode 6a (introducing an isolated methyl group in any position except the penultimate one) is used most commonly. For one paraffin it applies eight times in the same molecule. A correlation of fiftyfive of its applications indicates a mean increment of 0.0012 in density and 0.0004 in refractive index as compared with the corresponding (longer) isomer without the methyl group. These increments are independent of molecular weight. The increments for the other modes are calculated from the ratios to the increments of mode 1 as found in Table I. Mode 4a (introducing a methyl group into a penultimate position) has ratios falling rapidly with increasing carbon content, and it is only 0.53 at Cll. Results are fairly consistent if it is assumed that this ratio decreases one tenth of its value for each additional carbon atom. This gives the sequence CIS0.48, CIS0.35, C ~0.21, O CBO 0.07. It practically vanishes at high carbon content, so that a high "isoparaffin" has almost the same density and index as the normal one with one less carbon atom. The ratio for mode 2 (lengthening an ethyl group) is assumed to drop 0.02 for each additional carbon atom, giving 0.83 for CIZ, etc. The other modes employed in Table VI1 also are assigned ratios which are linear extrapolations of those used previously (9) : Ratio (0.9) n - 6 2 0.90 O.OO5n Constant inorements 0.0012 and 3c' 0.0004 (see text adove) 1.15 0.05n -0.05 0.20n 8db 8a d Substituting ethyl fon methyl in MeCHRz. 6 Substituting ethyl for methyl in MeCR:. c Introducing a second methyl grou into a penultimate position. d Substituting methyl for H in CHfEa.
Mode
1
Ratio 1.00 1.07 0.02n 0.86 0.06n
-
+ +
Mode 4a Sac 6a
-
n
Mode
Ratio
4a4
0.17
Density
Refractive Index
0 0017
0.0009
0.7976 Observed 0.8006
1.4463 1.4463
The calculated value for refractive index agrees precisely with the observation, a coincidence. The discrepancy for the density is moderate. The refractivity intercept, 1.0460, from the observations is lower than would be expected, 1.0477, for a tetracosane; therefore the calculated properties (which give a refractivity intercept 1.0475) are mutually more consistent than those observed. Most of the observations in Tables I11 to VI1 are checked by the calculations within 0.0020 and therefore are probably reliable, at least to that extent. If within that limit, the observations are preferred to the calculated values since the precision of calculation is not better than this. The other observations may be open to some doubt. However, when there is a high concentration of branches, as in the pentamethylheptanes and hexamethylhexane (Table VI), the calculations may be less accurate because of less typical application of the modes. Most of the discrepant observations seem to be high, suggesting the possible presence of olefins or oxygen compounds in the samples,
+
[TIES AND
REFRACTIVE INDICES OF DODECANES
Q
These ratios are multiplied by the appropriate increments in calculated values in Table I to get actual increments. The other modes of the former paper (9) are not required. The p r o p erties of the paraffins above dodecanes are calculated only by what seems the simplest method; which is shown in Table VI1 by the succession of modes listed. A subscript means that the same mode is used the number of times indicated. The precursor (given in parentheses) was either listed previously (9),or its properties were calculated by an equation of Tables 11,111,or V. When no precursor is given, the parent normal paraffin is understood. The method of calculation is illustrated with 2,ll-dimethyl5,8-diisoamyldodecane, selected because five different modes are employed. These modes are given as subscripts to the carbon atoms thus introduced. The properties of the precursor, %butyldodecane, are calculated from the equations of Table 11. The increments for mode 6a are subdivided because thosesssigned to that mode are in addition to those for the extra carbon atom according to Table 11, from which the properties of the precursor were derived. (In other words, the properties of 5-methyl-8-nbutyldodecane result from adding 0.0012 and 0.0004, respectively, to those calculated by the equations of Table I1 for Cn, in the
-
___
Isomer n-Dodeoane 3-%fethy~undecane 4-Met hylundecane 3-Ethyldeaane ( 1 7 ) 5-Ethyldecane 2 5-Dimethyldecane 2:B-Dimethyldecane 2 9-Dimethyldecane 3:3-Dimethyldecane
(4)
5-n-Propylnonane 2,2,4-Trimethylnonane 2-Methyl-5-n-propyloctane 3 6-Diethyloctane 4:5-Diethyloctane 2,3,6,7-Tetramethyloctane 3,3,6.6-Tetramethyloctane 2,6-Dimethyl-4-npropylheptane 2,6-Dimethyl-3-isopropylheptane 2,2,4,4,6-Pentamethylheptane 2,2,4,6,6-Penta2,2,3,4,5,5-&examethylhe tane (3)
Modes Table I 1,3a,6a 1 2 6a T(adleII1 Table111 1,4a,6a 9 1,4a,6;,9 TableIV
-d '-: Calcd. 0.7494 0.7504 0.7502 0.7568 0.7568 0 7449 0:7456 0,7435
1,3b,7a Table I1
0.7553 0.7542 0.7547 0.7550
Obsvd. 0.7487 0.7527a 0.7514 0,7519O 0.7560 0.7427a 0.75731a 0.74916
0.7466
-so-
Calcd. 1.4219 1.4225 1.4222 1.4251 1.4251 1.4194 1.4199 1.4189
Obsvd. 1.4216 1.4237'" 1.4231 1.422W 1.4251
1.4247 1.4240
1.4225 1.4333a
l.4243?"
....
1.4189 1.4198
1,5a,6a
0.7449
2,4a,9 3c 9 Tible V
0 7497
0.7495" 0.7640 0.7675 0,7647 0.7632
1.4221 1.4225" 1.4290 1.4316 1.4280 1.4279
4h, 6 b , 9
0.7638 0.7628'"
1.4287
3b, 7a
0.7622
....
1.4278 1.423? 1.4192 1.4182
1.4273O
2, 4a
0 7453
0.7443
4a, 4h, 9
0 7635
0.7654
4a, 5c, 7c
0,7683 0,7638
1,4257
i ,4277
5% 6a
0.7398 0.74777
1.4165
1.4187a
1 ,4365
1.4402?"
methylhexane (1) 5h, 6e 4 Corrected to Z O O C. b Calculated previously (6, 7).
0 7790
0.7925V
1.4283 1.432?
INDUSTRIAL AND ENGINEERING CHEMISTRY
260
Vol. 36, No. 3
BOlLLVG POINTS
TABLE VII.
DENSITIESA N D REFRACTIVE INDICBS OF HIGHERPARAFFINS
n Parafin Nodes 6a 13 5-hlethyldodecane 13 2,5-Dimethylundecane (f 7 ) 6a,4a 14 3-Methyltridecane (15) 6a 14 2,7-Dimethyl-4-isobutyloctane (4-n-propyloctane) a 4as 14 2,7-Dimethyl-4,5-diethyloctane (4 5-diethyloctane) 4a2 16 2,6,iO-Trimethyldodecane or f arnesane 6as,4a 15 4-Methyl-6-n-propylundecane (n-propylundecane) 6a 16 6 9-Dimethyltetradecane 6a2 16 7:8-Dimethyltetradecane (4,5-dimethylnonane) IS 16 5,7-Diethyldodecane (ethyldodecane) 6a,3c 16 4,7-Di-n-propyldecane (n-propyldecane) 6a, 3c, 2 17 5,5-Di-n-butylnonane 8a,3d,2,1 (n-butylnonane) 18 2-Methylheptadecane 4a 18 3,12-Diethyltetradecane (13) 6a, 3 c (ethyltetradecane) 20 2-Methylnonadecane 4a 20 2 6-Dimethyloctadecane 6a, 4a 20 2~6,10,14-Tetrarnethylhexadecane or phytane 6es, 4a 20 5,7,9-Triethyltetradecane (ethyltetraclecane) 6a2, 3c2 21 2-Methyl-4-isobutylhexadecane (n-prop ylhexadecane) 4az 22 2,9-Dimethyl-5,6-diisoamyldecane (16) (5,6-di-n-butyldecane) 4a4 24 2-Methyltricosane 4a 24 4,8,13,17-Tetramethyleicosane or bixane 6a4 24 2,11-Dimethyl-5,8-diisoamyldodecane (n-butyldodecane) 6a, 3c, 2, 1, 4a4 26 13-Methylpentacosane 6a 26 11-Neopentylheneicosane (n-prop ylheneicosane) 4a,5a 26 5,14-Di-n-butyloctadecane (n-butyloctadecane) 6a, 3c, 2, 1 26 3-Ethyl-5-(2-ethylbutyl)octadecane (n-butyloctadecane) 6az, 3c9 26 6,11-Di-n-amylhexadecane (n-amylhexadecane) 6 a , 3c, 2, 1s 31 2,6 12 16-Tetramethyl-9-(2 6-di~(n-octylheptadecane) e ~ h y l o c t yheptadecan: l) 6a3, 4a3 32 16-Methylhentriacontane 6a 46 4,8,13,17,22,26,31,35-Octamethyloctatriacontane or dibixane 6as 48 7,lB-Dimethyl 9,11,12,14-tetran-hexyldocosane (11,l2-dihexyldocosane) 6a4,3c2,21,
-,d20Calcd. Obsvd. 0.7580 0.7576 0,7537 0.7680 0.7644
0.7657
0.7563 0.7704
0.7767?
--?I
_...
y--.
1.4249 1.425Ob 1.4310 1.4328
0.7874
0,7921
1.4411 1.4430
0.7854
0.7858
1.4396 1.4369
0,7827 0.7841
1.4385 1.4368
0,7980 0.7790 0.7926 0.7860 0.7871
1.4470 1.4376 1.4438 1.4414 1.4418
0.7700?b 0.7806b 0.7924 0.7864b
,
1.43601b 1.4378b 1.443Ob 1.4416b 1.44186
.
0.7895 0.7901a 0,8032 0.7988
1.4425 ... 1.4489 1.44411
0.7900
1.4424 1.4419a
0.7945 0.7984 0.7962 0.7978b
1.4436 1.4467
1.4442 1.4462* 1 ,4502
0,8030 0.8054
1,4493
0,7976 0.80066
1,4463 1.4463
0.8030
0.8031b
I
Calcd. Obsvd. 1.4263 1.4244 1.4240 1.4242 1.4297 1.4307
0,7676 0.7716b 1.4312 1.4323b ,7744 ,7724b 1, 4340 .4326 0.7761 0,7787 1.4356 1.4348
1.4502
1.44886
0.8025 0,8029 0.8081 0.8075
1.4490 1.4517
1.4491 1.4508
0.8121 0.8109
1.4539
1.4521
0,8081 0.8068
1.4517
1.4502
0.8115
1.4529 1.4516b
0.8114
o.siii?b
1.4546
0.8310
0.8292b
1.4633 1.4630b
i . 4 m ? b
Normal ‘boiling points for straight-chain paraffins are correlated in Table V of a former paper (8) Observed normal boiling points (above 720 mm.) are given in the literature for only thirty-two branched-chain paraffins above undecanes. These are listed in Table VI11 and compared with the calculations by methods similar to those used in Tables V I and VII. The observations are corrected to 760 mm., when necessary, by the equation dtb/dp
=
0.05’ C./mm.
Tfle agreement in Table VI11 is relatively poor. Only fourteen boiling points check within 5’ C., although this is comparable .to an error of 0.0100 in density (8). I n some cases the discrepancy may be due to mere casual observation of the boiling point or neglect of stem correction, since observations are usually lower than calculations. Although the latter are extrapolations, it seems unlikely that they are much less accurate than those for the other properties. The normal boiling points of several other higher branched-chain paraffins could be estimated from those observed at 15 mm. or other pressures. But they are not included in Table VI11 because the additional error introduced by this procedure and the uncertainty of the pressure at the surface of the boiling liquid make the results no more concordant vith the calculations. Although melting points are recorded for many of these higher paraffins, it does not yet seem possible t o make a general correlation for branchedchain isomers for that property. LITERATURE CITED
(1) Backer, H. J., Rec. trav. chim., 58, 660 (1939). 0,8343 0.8875’lb 1.4639 .. . (2) Badin, E. J., J . A m . Chem. SOC.,65, 1812 (1943). 1s a Xames in parentheses are precursors for the calculations. (3) Bartlett, P. D., Fraser, G. L., and Woodward, Corrected t o 20° C. R. B., Ibid., 63, 497 (1941). (4) Campbell, K. N., and Eby, L. T., Ibid.,62, 1800 (1940). TABLEVIII. BOILINGPOINTS OF HIGHER BRANCHED-CHMN ( 5 ) Cosby, J. N., and Sutherland, L. H., Refiner Natural GasoP~RAFFINS line Mjr., 20, 471 (1941); Whitmore, F. C., and co-workers, Boiling Point, a C. J . Am. Chem. Soc., 64, 1360, 1801 (1942). n Paraffin Calculated Observed ( 6 ) Doas, M. P., “Physical Constants of Principal Hydrocarbons”, 208.8 209.8 4th ed., New York, Texas Go., 1943. 12 4-hlethylundecane 12 3-Ethyldecane (16) 209 I 1 202? (7) Egloff, Gustav, “Physical Constants of Hydrocarbons”, Vol. 12 2 6-Dimethyldecane 200.9 195 I, A. C. S. Monograph 78, New York, Reinhold Pub. Co., 12 ~ L - ~ r o p y l n o n a n e 206.6 204 1939. 12 2 2 4-Trimethylnonane 190.5 191.6 (8) Francis, A. W., IND. ENG.CHEM.,33, 554 (1941). 12 Z~~~ethyl-5-k-propylootane 199.0 189? 201.1 203 (9) Ibid., 35,442 (1943). 12 3 6-Diethyloctane 12 4:5-Diethylootane 200.7 192-4? (10) Krafft, F., Ber., 40, 4783 (1907). (11) Kurtz, S. S., and Lipkin, ?VI. R., J . Am. Chem. Soc., 63, 2158 12 2,2,7,7-Tetramethyloctane 179.9 185-90? 12 2 4 5 7-Tetramethyloctane 191.5 208-lo? (1941); IND. ENG.CHEM.,33, 779 (1941). 12 2:6IIjimetl~yl-4-n-propylheptane 191.1 184? (12) Kurtz, S.S., and Ward, A. L., J . FranklinInst., 222,563 (1936). 12 2,6-Dimethyl-3-isopropylheptane 194.6 186-81 (13) Landa, S., and Habada, M.,Collection Czechoslov. Chem. Com12 2,2,4,4,6-Pentamethylheptane 184.5 184.0 mun., 8 , 473 (1936). 171.8 177.1 12 2 2 4 6 6-Pentamethylheptane 12 2:2:3:4:5,5-Hexamethylhexane (I) 189.6 191-2 (14) Maman, A., P u b . sci. tech. minist6re air (France), 66, 32 (1935). 13 5-Methyldodeoane 228.0 227 (15) Petrov, A. D., and Chel’tsova, M.A., Bull. acad. sei. U.R.S.S.. 224.4 228.0 1940, 267. 13 4-Ethylundecane 215 220.1 13 2,s-Dimethylundecane (16 ) (16) Petrov, A. D., and Kaplan, E. P., J . Gen. Chem. (U.S.S.R.), 12, 218.3 219.8 13 2,10-Dimethylundecane 99 (1942). 220.8 225.8 13 4-n-Propyldecane (17) Petrov, A. D., Pavlov, A. M., and Makarov, Y . A,, Ibid., 208 212.8 13 2,5,9-Trimethyldecane 11. 1104 (1941). 2181 225,8 13 o-n-Butylnonane 230.9? (18) Schiessler, R. JV., and co-workers, Petroleum Refiner, 22, 392 244.0 14 4-n-Propylundecane 225? 2 3 4 , j 4,5-Di-n-propyloctane 14 (1943). 223 7 215-71 (19) Schmidi, A. W., Schoeller, V., and Eberlein, K., Ber., 74B, 1313 14 2,7-Dimethyl-4,5-diethyloctane 15 5-n-Propyldodecane 261.3 262.71 (1941). 261.3 244? 15 6-n-Propyldodecane (20) Ziegler, K., Grimm, H., and Willer, R., Ann., 542, 94 (1939). 262.7 243? 15 6-Methyl-7-ethyldodecane 15
16 18 20
4-bI~thyl-6-n-propylundecane
7 8-1)imethyltetradecane 2LMethylheptadecane . 3-E1hyloctsdecane
’
.
253,8
___
278.9 21 1 340.3
237? 270?
---
211
341
PRESBNTBDbefore the Division of Organic Chemistry a t the 106th Meeting of the AMERICAN CHDMICAL SOCIDTY, Pittsburgh, Pa.
B COMPLEX VITAMINS In Sugar Cane and Sugar Cane Juice
N T H E United States the two most inexpensive sources of energy-producing foods are cereal products and cane sugar (6). In recent years workers have repeatedly demonstrated that important B complex vitamins, which are found in unprocessed cereal products, are greatly reduced in quantity during processing (1, 3, 4, 8, 1S, 18). The essential facts were recognized many years ago by those who advocated the advantages of whole-wheat flour (9, 10). Investigators have clearly demonstrated that refined sugar is devoid of thiamine (6, 7, 11, 13, 19) and presumably of other vitamins. The present investigation of the water-soluble B complex vitamins of sugar cane and sugar cane juice was undertaken to discover to what extent the processes of sugar refining create this nutritional disparity by removing or destroying certain vitamins naturally associated with sugar in the cane.
I
William I?.Jackson1 and Thomas J. Macek MERCK
waxing. All samples were stored under refrigeration until assayed. In Cuba a total of thirty-six different samples of juice were similarly collected from an equal number of different varieties of cane. I n addition, representative pieces of whole sugar cane were collected from thirty-nine different varieties. All juices and canes were preserved as described. I n both Louisiana and Cuba the samples were collected from plantations in different parts of the state and island, respectively, and thus are representative of several types of soils. The age of the cane varied from 3 months to 2 years, and both plant and ratoon type were sampled. For the most part the Louisianan and Cuban canes were 9 and 11 months old, respectively. On arrival at the laboratory the preserved juices were immediately assayed for sucrose, thiamine, riboflavin, niacin, pantothenic acid, and biotin. The pieces of whole cane were freed of their wax coating, and a portion of each piece was pulped with the aid of a mechanical saw, a knife, and finally a laboratorytype meat grinder. A weighed quantity of the fresh pulp was pressed on a Carver laboratory press, and the juice was col-
EXAMINATION OF SUGAR CANES AND JUICES
The samples of cane juices and canes used in the present investigation were collected in Louisiana and Cuba. I n Louisiana ten samples of juices were taken from three varieties of caneLe., Canal Point 28-19, Coimbatori 281, and Coimbatori 290; two additional samples were obtained from mixed canes direct from the crusher. The canes were freshly cut in the field, and the juices were immediately expressed in a laboratory crusher or in factory crushers. The juices were preserved by the addition of 2 0 3 0 % alcohol. Samples of whole sugar cane, consisting of two or three segments from both the top and bottom of several canes, were also taken directly from the field and preserved by
TABLEI. SUCROSE AND VITAMIN CONTENTS EXPRESSED FROM SUGAR CANE Variety of Cane C.P. 28-19 c o . 281 co. 290 Mixed Mixed Minimum Average Maximum Badilla Baragu& Canalpoint Coimbatori Cristalina Fajardo Mayaguez MediaLuna Palma POJ SantaCruz Minimum Average Maximum a Samples.
1
izh ... lb 35
2b 2) 2a lb
6b 20 1b
158 lb
... 36a , . ,
Louisianan Cane Juiaes 18.24 0.062 0.039 14.83 0.099 0.052 15.38 0.084 0.055 13.85 0.049 0,049 11.41 0.136 0.071 11.41 0.049 0,038 14.76 o . m o 0.053 18.24 0.136 0.077 Cuban Cane Juices 20.19 0.179 0.112 18.66 0.229 0.070 16.41 0.259 0.070 16.66 0.197 0.110 16.80 0.095 0.075 16.61 0.255 0.140 19.69 0.141 0.086 17.23 0.180 0 081 19.67 0.103 0.059 17.27 0.186 0.082 19 41 0.133 0.062 10.25 0.086 0.051 17.87 0.179 0.083 23.04 0.359 0.174
2.84 2.71 3.76 5.41 5.80 2.53 3.70 5 80 1.65 1.76 2.28 3.04 2.53 1.27 1.20 1.38 1.60 1.53 1.60
0.76 1.69 3.34
0.721 0.829 0.703 0,861 1.063 0.657 0.834 1.063
Present address, Wyeth Incorporated, Philadelphia, Pa.
TABLE 11. SUCROSE AND VITAMIN CONTENTS OF WHOLE SUGARCANES
O F JUrCES
Vitamins, Micrograms/Gram of Juice No. of Samples ' ThiPantoor Sucrose, amine Ribo- thenio Species HC1 flavin acid Niacin Biotin
Za 6= Za 1" la
k COMPANY, INC., RAHWAY, N. J .
Variety of Cane
0.034 0.034 0.025 0.022 0.028 0.022 0.031 0.038
C.P. 28-19 c o . 281 c o . 290 Minimum Average Maximum
Badilla BaraguB Canal Point Coimbatori Cristalina Fajardo Mayaguez Media Luna Palma POJ Santa Crus Uba
0.975 0,030 0.814 0.033 0.768 0.038 0.797 0.042 0.538 0.020 0.914 0.041 0.813 0,027 0.956 0.028 0.697 0,025 0.720 0.029 0.718 0.027 0.530 0.016 0.765 0.030 1.06 0.045
Minimum Average Maximum
Vitamins, Micrograms/Gram of Cane ThiPantoNo. ,of Sucrose, amine Ribo- thenic Species % HC1 flavin acid Niacin Biotin
.. .. .. .. .. .. 1
3 2 2 2 1
6 2 3 15 1 1
..
39
..
Louisianan Whole Canes 11.66 0.328 0.203 11.08 0.499 0.250 11.84 0.332 0.202 0.245 0.149 .. 0.398 0.222 0.576 0.261
0.040 0.042 0.027
1.93 3.36 4.27
1.38 1.60 0.988 0.851 1.31 1.62
Cuban Whole Canes 14.50 0.300 0.230 11.21 0.428 0.309 12.82 0.415 0.169 12.98 0.623 0.237 12.48 0.565 0.189 11.81 0.475 0.185 13.89 0.342 0.227 10.23 0.375 0.301 15.22 0.348 0.216 10.92 0.451 0.245 15.10 0.334 0.396 12.44 0.194 0.212
1.68 1.27 2.16 2.33 1.51 0.950 1.39 2.00 1.30 1.12 1.41 2.13
1.95 1.75 1.74 1.31 1.12 1.80 1.79 2.04 1.67 1.38 1.51 1.68
0.073 0.037 0.071 0.054 0.027 0.071 0.054 0.065 0.046 0.047 0.044 0.044
5.30 12.24 18.95
0.543 1.41 3.47
0.888 1.56 3.03
0.009 0.050 0.106
... . . ..
0.194 0.129 0.420 0.241 0.793 0.396
3.61 2.81 3.78
0.023 0.036 0.048
b Species. d
261
