September 1950
INDUSTRIAL AND ENGINEERING CHEMISTRY
a d v i t y when blended in mineral oil; phosphites are superior to phosphates, and long chain aliphatic esters are superior to aryl esters. B. The addition of fatty acids esters, or sulfur improves the extreme pressure properties of bfends of both phosphites and phosphates. C. Chlorinated phosphorus esters, thiophosphites, and thiophosphates are useful extreme pressure additives. D. Phosphorus esters effect lubrication of steel by reacting chemical1 to form phosphide films which are smooth1 worn aray. dters containing chlorine form chloride-phos hi& films, but those containin sulfur form a sulfide-phosphide E. I n eneral t t e extreme remure activity shown by phoshites an{phos$ates is of ayower order than that shown by hogen-su ur a itives but is of the same order as the lead soapsulfur type additive.
fik.
ACKNOWLEDGMENT
The author wishes to express his thanks to Albright and Wilson, Ltd,, for gifts of chemicals and to Shell Refining and Marketing Company, Ltd., for the use of facilities to carry out tests on the four-ball machine,
1847
LITERATURE CITED (1) Beeck, O., Givens, J. W., and Smith, A. E., Proc. Roy. Soc. (London),A177, 90 (1940). (2) Beeck, O., Givens, J. W., and Williams, E. C., Ibzd., A177, 10a (1940). (3) Bowden, F. P., and Tabor, D., Ann. Repla. on Progrees Cham. (Chem. Soc. London), 42,20 (1945). (4) Davey, W., END. ENQ.CEEM.,42, 1837 (1950). (6) Davey, W., J.Inst. Petroleum, 31,73 (1945). (6) I W . , 32, 575 (1946). (7) Ibid., 33, 574 (1947). (8) "Organic Syntheses," Collective Vol. 11, p. 109, New York. John W h y & Sons, 1943. (9) Ibid., p. 598. (LO) Prutton, C. F., Turnbull, D., and Dlouhy, G., J . Inat. Petroleum. 32, 90 (1946). (11) Thorp, R. E., and Larren, R. G., IND. E m . CHEY.,41, 958 (1949). (12) Tingle, E. D., J. Inat. Petroleum, 34, 743 (1948). (13) West, H. L..Zbid., 34,774 (1948). RH~CEIVED November 23, 1949.
Amine Activation of 41' F. Butadiene-Styrene Copolymerization ROMAN SPOLSKY AND H. LEVERNE WILLIAMS Polymer Corporation Limited, Sarnia, Ontario, Canada
The use of polyamines with or without heavy metal salts or digested dextrose as activator for the polymerization of butadiene and styrene in emulsion at 41' F. has been investigated. The purified metal complexes with (ethylenedinitri1o)tetraacetic acid were not superior to the impure materials. A number of polyamines were found to be suitable activators in the absence of ferrous sulfate but were generally better when some ferrous iron was present. However, the effectiveness of the polyamines dropped rapidly in the absence of sugar. By adjustment of the concentrations a suitable recipe was developed using tetraethylenepentamine as sole activator. Its effectiveness was enhanced by sugar but diminished by ferrous iron under these experimental conditions. No suitable sugar-free recipe activated with (ethylenedinitri1o)tetraacetic acid alone was evolved in contrast with the results obtained at lower polymerizationtemperatures.
T
H E essential change in the polymerization recipes required for the production of cold rubber was the replacenient of the potassium persulfate initiator used in the production of GR-S by a more complicated redox initiatory system. The new systems are usually composed of cumene hydroperoxide (CHP), ferrous pyrophosphate, and often digested dextrose. Many variations of this initiatory system have been studied. Although improved hydroperoxides are a suitable means of advancing cold rubber technology there has also been some interest in new activators for the decomposition of hydroperoxides (7, 8). The earlier paper in this series (7) described the use, in conjunction with alkali and dextrose, of a number of heavy nietals complexed with various chelating agents. In the course of this work it wee observed that the chelating agent (ethylenedinitri1o)tetraacetic acid was an activator. in the absence of heavy metal ion. Horner (6, 8 ) subsequently reported that
tertiary amines such as dimethylaniline activated the bulk polymerization of styrene using benzoyl peroxide, and that primary and secondary amines were inhibitors of such polymerization. W'hitby (IS) showed that in the emulsion polymerization of styrene and of styrene and butadiene a t 10" C. polyalkylene polyamines were highly effective activators of polymerization without heavy metal salts or sugar. The data below extend the polyamine activation to a commercially used 41' F. recipe and clarify some of the interrelationships between the heavy metal, polyamine, and sugar. EXPERIMENTAL
The techniques were essentially the same as those in the earlier report (7). The recipe used approximates type X-478. I n general the aotive ingredients were as follows: Butadiene Styrene Water MTM-4 Dresinate 214 Daxsd 11 KCl
Parts 72 28 180
0.24
4.7 0.1 0.6 0.09
0.1
1 .o
0.10
0.028
The only change was to replace the ferrous complex by the appropriate experimental activator. Other changes will be noted below. Materials, from the sources indicated, were used am received but concentrations refer to pure active ingredients. The effect of metal salts in the presence of Kalex K [%yoaqueous solution of potassium (ethylenedinitri1o)tetraacetate from Hart Products Company of Canada Limited] on the p o l y m e h tion rate was reported earlier (7). Since the preparation of the complexes by mixing Kalex K and metal salt solutions waB not uniform it was felt that the use of pure complexes would give more reliable results. One-half millimole of metal complexes
1848
I N D U S T R I A L A N D E N GI I N E E R I N G C H E M I S T R Y
AS ACTIVATORS IN SUGAR RECIPE TABLEI. METALCOMPLEXES AT 41 F.
Activator Metal complex' Fe disodium Cu disodium Re' disodium Sn + disodium Zn disodium M l g r + disodium B s + dilithium Pb + + dilithirini Co + + dilithium Ca + dilithium Co disodium Cd + disodium No metal Fe disodi,um C u + + disodium Cd disodium Co + disodium Fe + + disodium + + +
+
+
+
+
+
+ +
+
+
+ +
+ + +
Part 0.20 0.20
0.17 0.23 0.20
0.18 0.22 0.25 0.18 0.17 0.15 0.14
0:io 0.20 0.14 0.18
0.20
Sequestrene AA, part 0.13 0.13 0.18 0.17 0.17 0.17 0.15
0.15 0.15 0.16 0.15 0.21 0.30 0.26 0.26 0.43 0.30 Versene Fe-3
%. %S!EX+Z Conversion/ 17 hr. 45.0 25.4 23.1 18.3 16.8
17.8 12.9 12.1 7.3 4.3 2.9 1.4 18.2 44.0 87.8 17.4 9.5 38.8
19 hr. 49.4 22.4 26.3 ,22.0 28.6 19.6 l7,5 16.5 5.4 15.8 2.9 1.9 12.8 46.7 34.9 23.8 10.3 43.9
Hr.
1.65-2 . G O
1,50-1.23 1.35-1.38 1.08-1.16 0.90-1.50 1.05-1.03 0 76-0.92 0.71-0.87
0,43-0.28 0,25-0.83 0.17-0.15 0.08-0.10 1.07-0.67 2.60--2,45 2,22-1 .R4 1.02-1.25 0.56-0.54 2.28-2.31
0,08" Versenste fromi Bersw orth Chemical Co.
per 100 grams of monomers was dissolved in the alkaline solution (potassium hydroxide) of Sequestrene AA [100% (ethylenedinitri1o)tetraacetic acid from Alrose Chemical Company]. The total concentration of potassium (ethylenedinitri1o)tetraacetate was 0.45 part per 100 parts of monomers as in previous tests. The pH was adjusted to approximately 10 and the activator stored under nitrogen until used. The data are shown in Table I. The order in which various metals are effective in increasing the conversion was, with few exceptions, similar to that found earlier with Kalex-metal salt activators (7). Iron complexes are best in both series. The commercial ferrous complex activator yields results more like ferric-Kalex K than ferrousKalex K. The red-brown color of commercial complex suggests that the iron is present in the ferric rather than ferrous state. Some activating effect appears with cupric or beryllium disodium complexes. Mixed sequestering agents, ferrous disodium complex and Versene Fe-3, do not result in an increased conversion. An increase in the amount of sequestering agent does increase the conversion when the less effective metals are used. A similar study was undertaken by substitution of amines and polyamines for the metal complex and (ethylenedinitri1o)tetraacetic acid. The results are in Table 11. Aliphatic amines with one or two carbon atoms do not form suitable activators for polymerization. The higher homologs are better. Primary, secondary, and tertiary amines with hydroxy or carboxy groups attached also have no activating power. The activating properties of a compound are increased greatly by the presence of another amino group. Further increase of the number of amino groups in the compounds makes them more applicable for activation polymerization. Whitby (1%) attributes this ability to activate to the presence of primary and secondary amines. This assumption is not supported by the present authors' data; rather, the effectiveness is nearly proportional to the amine content of the polyethylene polyamine. This would indicate that primary and secondary amines are equivalent in respect to their activating properties. Propylenediamine is equivalent to ethylenediamine. Substitution of one amino group by hydroxyl in diethylenetriamine decreases its activating power slightly. Polyamines with acetic acid or aalicylaldehyde groups attached to the nitrogen atom usually show greater activating effect, except (diethylenetriamine)tetraacetic acid. Compounds with a two-carbon bridge between two amino groups seem to be most suitable for amine activation. Compounds with two amino groups joined by a carbonyl or a thiocarbonyl group are poor activators. Aromatic amines seem to be less active. Aniline does not activate, p-toluidine only slightly, whereas para derivatives of aniline, pphenylenediamines, di- and triphenylamines, and diazo-
Vol. 42, No. 9
aminobenzene retard the polymerization reaction. p-Hydroxyphenylglycine is a mild activator. The alicyclic secondary amine, thialdine, and the tertiary amine, phenylmorpholine. do not show any activating effect. Heterocyclic tertiary amines make surprisingly good activators. Even pyridine with one nitrogen atom results in 17,9% conversion in 17 hours. Compounds with two nitrogens in the ring structure such as bipyridine and phenanthroline are more effective. The influence of varying the concentration of polyamine in the homologous series of polyethylene polyamines is shown in Table 111. In general the degree of conversion increases with increasing concentration of polyamine with either CHP or diisopropylbenzene monohydroperoxide (DIBHP). Of interest, too, is the influence of emulsifier type (Table IV) and of pH (Table V). While fatty acid soap appears to yield faster rates, the optimal pH (pH 10) of the Dresinate soap is lower than that observed by Whitby (1%)for fatty acid soap. Typical timeconversion curves are in Table VI. The conversion with the polyamine is very similar to that observed with ferrous ophenanthroline but more linear with time.
TABLE11. AMINE ACTIVATIONIh'
SUG.4R
RECIPEAT 41" F. % Conversion
Amine o-Phenant hroline Tetraethylenepentamine Cyclohexane-o-diarninotet raac e tic acid 2 P'-Aipyridine Disaljcylalethylenediamine Veraene Fe-3 (powder) Triethylenetetramine Diethylenetriamine (2-Aminoet hy1amino)ethanol (Ethylenedinitrilo) tetraacetic acid Versene Fe-3 34% solution
Part Source' 0.179 G.F. Smith 0.189
Eastman
0 . 3 5 8 Alrose 0 . 1 5 6 0.F. Smith
17 hr. 45.2
19 hr. 20 hr. 47.3
..
35.4
..
..
27.9 25.4
33.9 27.6
..
Du Pont Bersworth Eastman Eastman
21.2 21.1 20.8 20.1
2i:2
0.104
C&CCo.
19.7
20.5
0.380
Hart Prod.
19.6
28.8
..
0.170 0.079 0.074 0.060
Bersworth Nichols c &CCo. Eastman
18.8 17.9 17.2 14.5
19.9
..
..
1 .
48.0
..
0.266 0.170 0.146 0.103
..
ZFG.
25.5
..
..
.. I
3i:5 30.6
.
..
Pvridinr .. .. .. 14.2 .. P;opylenediamine 17.3 ,. .. Ethylenediamine (Diethy1enetriamine)tetraacetic acid (3.71) 11.9 0.446 Alrose wm.) Dibexylamine 716 7.5 0.187 Sharples Disalicylalpropylenediamine 0.280 Du Pont 7.1 -Toluidine 0.107 B D H 6.7 exadeaylamine 6.5 0 . 2 5 2 Armour 6.0 0 . 1 6 2 Armour Depylamine 0 . 0 7 6 Eastman Thiourea 4.7 Octylamine ,. 0 . 1 3 3 Armoui 4.6 .. 0.129 Eastman Quinoline 4.3 p-Hydroxyphenylgly.. 4.1 .. cine 3.4 0.167 Eastman Versene Fe-3, concn. 3.0 .. solution 0.170 Bersworth 2.9 1.8 2.3 Hydroxylamine 0 . 0 7 0 Merck 3:7 2.2 Nitrilotriacetic acid 0.191 Eastman i:1 .. 2.1 Diazoaminobenzene 0.197 Eastman 1.8 1.8 Diethanolamine 0.105 BDH 1.8 Hexamine 0.140 B D H No amine 1.6 .. Diacetyl-p-phenylene1.8 1.6 diamine 0 . 1 9 2 Eastman 1.6 p-Nitroaniline 1.6 0 , 1 3 8 Eastman 2.8 Aniline 1.5 0.093 BDH 2:0 .. 1.5 Thialdine 0.163 C & C C o . 0.060 Eastman 1.6 .. Urea 1.5 1.1 .. Triethanolamine 1.5 0.149 BDH i:o .. Methylamine HC1 1.5 0.068 Eastman 3:2 1.4 .. Ethanolamine 0.061 B D H 0.2 .. Phenylmorpholine 1.1 0.163 C & C C o . .. 0:7 .. Benzidine 1.0 0.184 B D H .. .. p-Chloroaniline 0.8 1.4 0 . 1 2 8 Eastman (2-Hydroxypropylenediamin0)tetraacetic 0.8 0.322 Alrose 0.8 acid 1.3 .. Eth lamine HCI 0.7 0.082 Eastman b:6 .. D ipEenylamine 0.7 0.169 B D H 0:0 .. 0.4 Dimethylaniline 0.121 Eastman 0.7 .. Triethylamine 0.3 0.101 Eastman p-Dimethylaminobenzaldehyde 0 . 1 4 9 Eastman 0.2 0.5 Triphenylamine 0.245 Eastman 0.2 013 .. Diethylamine 0 , 0 7 3 Eastman 0.2 0.2 Tetramethyldiaminodiphenylmethane 0 . 2 5 4 Eastman 0.1 0.3 .. G . F. Smith G . Frederick Smith Chemical Co * C & C Co., Carbide & Carbon Chedcals Gorp.: BDH, British Drug Hzuses, Ltd. I .
.. ..
H
..
..
..
.
I
..
..
.. ..
..
..
..
Q
INDUSTRIAL AND ENG INEERING CHEMISTRY
September 1950
IN SUGAR TABLE111. EFFECTOF ACTIVATOR CONCEN~RATION RECIPEAT 41 ' F.
Diethylenetriamine, Part
-
Aotivator Composition. Part 0 . 1 5 CHP 0 . 1 0 CHP % Conversion in 17 Hr.
ii:o
12.7 11.0 16.4 18.9 17.7 18.9 21.7
.. ..
....
0.6 0.7 0.8 0.9 0.1 0.1
.. ..
31.1 29.8 32.0 31.5 0 . 2 CHP 14.5 0 . 1 2 DIBHP 15.8
0.15CHP 15.7 0 . 0 9 DIBHP 17.4
0.2 Diethylenetriamine and triethylenetetramine 0 . 1 each Triethylepetetramine 0.2 0.1
Tetraethylenepentamine 0.1 0.2 0.3 0.4 0.6 0.6 0.7 0.8 1.0 1.2
'
-
0.lOCHP 16.5
*. .... 0 . 0 5 C H P 17.8
0 . 0 6 DIBHP 0.03 D I B H P 16.5 16.0 0 . 1 CHP a4.i
25.8 26.3 17.9 0 . 3 CHP 17.5 30.6 38.8 44.1
0 . 2 CHP 17.5 32.2 36.2 41.6 45.7 47.6 51.7 54.6
6311 6014 65.5 68.9
0 . 1 CHP 22.5 35.7 39.3 42.8 45.0 45.7 46.6 46.5
0 . 1 DIBHP 22.2 29.3 34.9 34.5 43:O
..
1849
increases rapidly when the pentamine concentration is decreased from 0.25 to 0.15 part. Having thereby established the polyamine concentration suitable for a sugar-free recipe, the effects of catalyst concentration, soap type, and pH were checked and time-conversion curves determined. The data indicated a practical commercial recipe had been attained. In the series with varying amount of catalyst (Table IX) the conversion rises slowly with the increase of catalyst concentration up to 0.1 part, then rapidly between 0.1 to 0.2 part, and finally its rise is slowed again at catalyst concentrations higher than 0.2 part. When smaller amounts of pentamine are used (0.1 part) the conversion increases more rapidly and 60% conversion in 17 hours may be obtained with less peroxide. Diisopropylbenzene monohydroperoxide is less effective than CHP when used in amounts below 0.2 part, but considerably better at higher concentration. The polymerization reaction proceeds uniformly with a steady rate (2.7% conversion per hour) up to 60% conversion, then the rate slows down. Soap flakes (potash ORR soap) yields around 1.4 times faster reaction rate than Dresinate 214 (Table X). Potassium stearate is also better than Dresinate 214. Potassium oleate, which allowed a very good conversion in the sugar-pentamine recipe, seems to be a poor emulsifier in sugar-free formula. Dresinate 781 in the presence of 0.5 part trisodium phosphate instead of potassium chloride results in a lower conversion than does Dresinate 214. The same conversion may be obtained by the increase of pentamine to 0.2 part and CHP to 0.3part. The rate of polymerization is greatly affected by the pH of the emulsifier system (Table XI). The minimal rate is observed at pH 11.2 (around 2.2% conversion per hour). The rate increases when the pH is either increased to 12 or decreased to 10. A pH of 10 shows the highest rate (3.3% conversion per hour). The optimal pH values for emulsifiers other than Dresinate 214 have not been determined.
'
The effect of the addition of ferrous sulfate may be quite marked (Table VII) in the sugar recipe. (Diethylenetriaminet tetraacetic acid and (cyclohexane-o-diamino)tetraacetic acid seem to be equivalent or a little better than (ethylenedinitri1o)tetraacetic acid for preparation of ferrous activators. They are aleo slightly better in iron free activation. @-Hydroxypropylene-1,3-diamino)tetraacetic acid activates very poorly in the absence of iron although better with iron; it is considerably less effective than (ethylenedinitri1o)tetraaceticacid. Of greatest interest is the effect of sugar concentration in the iron-free recipe (Table VIII). From 0.4 to 0.5 part sugar gives maximal conversion when the pentamine concentration is kept constant (1.0 part per 100 parts monomers) and the peroxide concentration is varied. This optimal conversion is about 1.4 to 1.5 times higher than the conversion in the presence of twice the amount of sugar. The conversion is lower for all sugar concentrations when smaller amounts of peroxide are used, but the curve, conversion versus sugar, does not change form. A conversion of 10% in 17 hours is not reached in charges with no sugar and 1.0 part pentamine. When the amount of pentamine is decreased (peroxide constant) the optimal sugar concentration shifts to the lower values. The optimal sugar amount for 1.0 part pentamine is 0.4 to 0.5 part; for 0.5 part pentarnine, 0.2 to 0.4 part; for 0.25 part pentamine, 0.15 to 0.2 part; for 0.15 part pentamine, 0.10 to 0.15 part; and for 0.1 part pentamine, about 0.05 part. In general, the optimal mole ratio, sugar to pentamine, is found to be close to 2 to 1. The conversion increases with the decrease of the pentamine concentration in absence of sugar. The Conversion is very low in the presence of more than 0.25 part pentarnine and it
TABLEIV. VARIATICYIN EMULSIFIERIN SUGAR RECIPE AT 41' F. (Activator composition: 0.3 part CHP, 1.0 part tetraethylenepentamine) 4 . 7 Parts Emulsifier/100 Parts Monomers % Conversion in 17 Hr. Dresinate 214 Hercules) pH 10.38) 49.0 38.5 Dresinpte 731 [Hercules) {pH 10.70) Potassium stearate (pH 10.50) 8 3 . 3 (prscoagulum) Potassium oleate (Beaoon) (PH 10.20) 77.9
TABLE V. EFFECTOF pH
IN
SUGARRECIPEAT 41' F.
(Activator composition: 0.3 part CHP. 1.0 part tetraethylenepentamine) Emulsifier pH % Conversion 10.25 51.6 11.22 46.3 11.60 88.8 11.97 30.6
TABLEVI. CONVERSION AS FUNCTION OF TIME IN SUGAR RECIPEAT 41 O F.
Reaotion Time, Hr. 1 2 4 6
8 9 10 12 14 16 16 18
Activator Composition, Part 0 . 1 4 FeS04.7HsO 0 . 3 CHP 0 . 2 o-Phenanthroline 1 . O Tetraethylenepentamine 0 . 1 0 CHP % . % % . % conversion conversion/hr. conversion conversion/hr. 0:0
14.8 20.0
4:5 3.7 3.34
32.4
3.6
41.3
3.44
52.2
3.48
57.9
3.22
8.3 13.8 23.8 29.2 31.5
8.3 6.8 5.9 4.9 3.9
36.9 41.8 44.6
3. 3.5 3.2
48.0 52.6
3.0 2.9
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
1850
VII.
T.4BLE
EFFECTO F IRON SALT(FeS04.7H20) ACTIV.4TION I N SUGAR RECIPEAT 41 ' F. Po!yamine,
E t h 4enediamine (Ethylenedinitri1o)tetraacetic acid (Cyclohexane o diamino)tetraacetio acid VerseneFe-3(powder) Diethy1enetriamine)tetraacetic acid (2-Hydroxypropylenediamino) tetraaceti(. acid
-
-
Part 0.060
ON AMINE
% Converaion in 17 Hr. (19 Hr.) with No iron 0,028 part 0.14 part 14.5 (17.3) 43.3 (43.0) 44.7 (46.3)
0.380
19.6(28.8)
55.8(61.7)
53.8(61.7)
0.358 0.170
27.9 33.9) 21.1 121.2)
44.3 (47.7) 42.4(45.5)
57.5 (61.8) 47.7(51.2)
0.445 20.2 (13.7)
55.1 ( 5 5 . 1 )
57.3 (57.5)
0.8 (0.8)
38.9(38.9)
37.3(37.3)
0.322
Vol. 42. No. 9
The time-conversion data in Table XI1 indicate a reasonably linear rate. The recipe is comparatively insensitive to oxygen (Table XIII). The indicated volumes of air or oxygen were injected into the 8ounce polymerization bottles containing a charge of about 150 grams. Pentamine activation appears to be suitable for use on a larger scale. The preparation of the activator is simple and iron salts are absent. The recipe with pentamine activator seems to give reproducible results. The following recipe is suggested by the above work. Parts Butadiene Styrene
72
Wbkr
TARIX \7111. EFFECT O F l>IGEBTEI) AT
Dextrose, Parts 0.00
0.05 0.10
F.
Activator Composition, Part Tetraethylenepentainine 1.0 1.0 1.0 0 . 5 0.25 0.15 0 . 1 CHP 0.3 0.2 0.1 0.2 0.2 0.2 0.2 Conversion in 17 Hr-.-7.3 8.1 4.4"12.9 31.8 60.7 57.5 . . . . . . . . 54.3 61.0 70.2 58.8 64.7 55.9 63.5 64.9 I j 5 . 8 68:O 63:5 38:O 79:2 64.1 62.1 4 8 . 7 . . . . . . . . 47.0 5 i : 4 43.4 30:5 7310 76:O 59:8 7 i : 7 47.3 40.4 .. 42.5 . . . . 7$:9 7011 57:6 4913 . . . . . . 60.8 56.3 43.7 45.5 . . . . . . 54.2 46.6 43.5 43.3 . . . . . . 51.6 48.0 44.2 43.0 . . . . . . 50.9 46.1 43.7 4 3 . 0
. . . . . . . .
0.15
0.20 0.25 0.30 0.40
0.50
0.60 0.80 1.00 1.20
. . . . . .
1.40
T.4RLK
41'
1)EXTKUSE I N SUG.4R
Ix.
RECIPE -
0.1 Diethylenetriamine O.1CHP 4.2
..
*. 2:s
.. ..
4.5 1214 14.8 16.8 19.4 19.8
E F F E C T OF CAT.%LYST CONCENTR.4TION O N S I W . i R -
FREERECIPEA Y 41 F.
0.025 0.04 0.05 0.075 0.10 0.12 0.15
0.20 0.25 0.30
TABLE s.
Activator Composition, Part 0.15 Pentainine __ 0.10 Pentamine CHP DIBHP Conversion in 17 Hr. 10.8 .. .. .. 11.4 14:s 15:2 17:4 18.7 19.8 20.2 29:4 26.6 25.1 24:s 32.3 4i:i 50:5 39:8 56.9 .. 61.9 63.9 .. 60.2 75.6 .. .. 64.9 79,l
--
EFFECT OF
EMULSIFIERS I V SUCtAR-FREE RECIWAT 41" F. 96
plI 11.19 11.20
K-soap flakes (Swift) Potassium atearate Potassium oleate RR478 (Beacon Co.) 11.14 Dresinate 731 10.4 (NarPOd instead of KCI) ~ 1 0 . 4 (Na8PO4 inatead of KCI) 10.4 (NarPOd instead of KCI) 10.4 bresinate 214 10.4
TABLE S I . KFFEUT OF pH
Pentarnine 0.1 0.1
CHP 0.2 0.2
Conversion in 17 Hr. 77.6 61.8
0.1 0.1 0.1; 0.2 0.2 0.1
0.2 0.2 0.2 0.2 0.3 0.2
19.2 29.3 31.6 25.9 50.0 56.0
IN
SVOAR-FRW RECIPEAT 4 1 " F. % Conversion
Emulsifier pH
I n 17 hr. 56.4 52.0
41 . a 48.6 36.0 49.1
32.0
MtM-4
Pentarnine CHP
I n 19 hr. 65.1 56.8 47.7 55.2 36.3 53.5 39.3
0.1
0.2
This recipe gives 60% conversion in 17 to 18 hours. When higher rates are desired, Dresinate 214 may be replaced all or in part by soap flakes (potash ORR soap), DIBHP catalyst may be used, or the temperature may be increased slightly. An attempt was made to use (ethy1enedinitrilo)tetraacetic acid without sugar. The results show that Kalex-ferrous complex is poor in the sugar-free recipes at 41 O F. Variation of the ferrous sulfate and (ethylenedinitri1o)tetraacetate over wide ranges, changes in pH of the activator, or addition of potassium hypophosphite or sodium thiosulfate was without effect. In subsequent work two formulas were used with no essential difference in the results obtained. Butadiene Styrene
Water
~
Catalyat, Part
Dresinate 214 Daxsd 11 KCl KOH
Dresinate 214 KO H KC1 Daxad 11 MTM C H P (100'7) Fe80r.7Hd Kalex K or Kalex Na
Recipe I 72 28
180 4.7 0.095 0.5 0.1 0.24 0.1 0.14 0.45 0.4
Recipe I1
72
28 200
6.0
0.1 0.5
0.24 0.2 0.2 0.45
....
The conversion waa increased by using fatty acid soap of D r e e inate 5-147 but the conversion did not go beyond 20% in 17 hours. The addition of methanol was without influence nor did a change to dodecyl mercaptan modifier help. Variation of the emulsifier pH from 10 to 12 was without effect. Increment CHP charge ttrid the use of potassium chloride, potassium sulfate, or sodium phosphate were ineffective. Reproducibility was very poor; the conversion varied from two to 14y0 in 17 hours for the witme charge formula. Blends of Kalex K and pyrophosphate, 50 to 50, in the ferrous activator give a rate of reaction of 4.6% conversion per hour while Kalex-ferrous activator gives only 0.8'% conversion per hour (Table XIV). Sugtr seems to play an important part in protecting the ferrous-Kales complex from fnst oxidation. The complex is not atable against autoxidation and oxidation by per compounds. The ycllow-brown color of the oxidized ferrous-Kalex complex may be easily detected in the sugar-free mixture after reaction. The rate of polymerization seems to decrease after a few houra but the addition of more activator maintains the initial rate of reaction for a longer time. Molecular oxygen inhibits the reaction in a way similar to peroxide (oxidizes-Le., deactivates the activator). There is some indication (Table XV) that the optimal conversion may be obtained a t lower sugar concentration, when Kales is decreased from 0.4 to O.'l part. Further decrease in Kalex to 0.05 part reduces the conversion to one third. Practically no conversion is shown in the absence of sugar. Higher
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
September 19%
1851
DISCUSSION
TABLE XII. TIME-CONVERSION CURVE FOR SUGAR-FREE RECIPEAT 41' F. (Aotivator composition: 0.1 part pentamine, 0.2 part CHP) % Conversion % Conversion/Hr. Hours 42666 2 3:8b,4.23 4 3.4 6 3.72 7 3.33 8 3.58 10 2.93 11 2.96,3.39 14 2.86 17 3.14 18 2.82 20 2.85 22 2.75 26
The activation of the decomposition of CHP can be accomplished in many ways. It would appear that the nature of the solvent is a factor ( 1 ), hence the presence of styrene in the locus of the initial step may be of assistance. Then too, the reaction between CHP and ferrous iron in emulsion copolymerisation appears to take place in the aqueous phase since the kinetics of the reaction in this phase (3)is more in agreement with current concepts of initiation (4, 9-1 I) than are the reactions in the oil phase
($1.
Thus, an activation system is suggested to be composed of a heavy metal complex stable at the reaction pH and optionally a compound acting as an antioxidant. This latter compound can be either an amine or a sugar such as digested dextrose, invert TABLE XIII. EFFECT OF OXYGENIN SUGAR-FREE RECIPE AT sugar, ascorbic acid, etc. Certain amines appear to have the cor41' F. rect balance of reducing and antioxidant activity to be suitable % Conversion in 17 Hr. activators alone. However, these may be enhanced by increasing No air or 0 1 the concentration of the amine and adding additional mild anti3 ao. of air 6 ao. air oxidant or oxidation promoter as required to balance these effects. 9 ao. air Their effectiveness may be enhanced also through increasing 3 ao. 01 6 aa. 01 their activity by formation of the ferrous chelate complex in a manner similar to that observed in biological systems. TABLEXIV. EFFECTOF BLENDSWITH PYROPHOSPHATE IN Some of the low results %reundoubtedly due to too rapid deSUOAB-FREE RECIPEAT 41 O F. composition of the peroxide so that ineffective combinations at % Conversion 41 O F. may become quite suitable for lower temperature polyKalex K Fe80k.7H;O KtPzOr CHP in 17 HI. merization. 0.3 0.25 0.1 88.5 0.. ?2 5 0.45
0.3 0.3
0.126
0.1 0.1
78.6 la. 7
ACKNOWLEDGMENT
sugar amounts seem to have 110 influence on the conversion. In the presence of iron salts the conversion increases with the increase of sugar amount. The poor conversians in the first two aeries of Table XV are probably due to the high alkalinity of 12.0). Dresinate 214 (pH
-
TAB= XV. EFFECT OF SUGARCONCENTRATION AT 41' F.
Sugar Parts/& Parts Monomers 0.0 0.2 0.4 0.6 0.8 1.0 1.2
Aativator composition, Part Kalex 0.4 0.4 0.4 0.2 0.1 0.1 0.06 CHP 0 . 2 0 . 1 0.1 0.1 0.1 0.1 0.1 Fe804.7HaO 0.028 % ' Conversion in 17 Hr.0.1 0.2 0.2 2.0 0.1 4.9 i:s 1.4 1.9 6.8 26.0 34.0 4.1 6 . 6 8 . 3 14.6 2.3 0.2 1 . 6 0 . 3 1 2 . 1 12.7 1 8 . 7 3 9 . 8 6.1 42.8 6.2 1 . 6 0.6 1 1 . 0 1 3 . 6 16.7 2 . 6 1 . 1 1 3 . 7 9 . 9 1 4 . 3 45.4 6.9 1 . 1 0 . 7 18 3 8 . 6 16.4 47.7 6.8
-
..
0.06 0.1
Fe8Oa.* 7510 0.028
-4.0
25.2 31.4 36.6 89.7 45.0 44.3
On the basis of these tests the authors conclude that a sugarfree recipe for &lex activation has not been developed under the conditions used here. In the absence of sugar the addition of ferrous salts to polyamine activators may have an adverse effect (Table XVI).
TABLE XVI. EFFECTOF FERROUS IRON IN SUGAR-FREE POLYAMINE RECIPEAT 41 ' F. % Conversion FeS04.7Ht0 Added 0.14 0.028 0 ,026 part Na Kalex 0.028 0.028 0.0028 0.00028 0.000028
+
0.OOOOOO
6 hr.
13 hr.
i:2 26.0 36.3 a3.2
23:o 45.5 51.3 49.2
.... ..
.. .. ..
17 hr. 1.2 6.1 6.8 3.7 27.1 46.9 57.7 60.7
19 hr. 0.9 7.6 7.1
.... .. ....
20hr.
.. ..
.. 32:O 62.8 72.8 72.5
The authors thank Polymer Corporation Limited for permirsion to present this paper. The assistance of G. Vincent ie gratefully acknowledged. LITERATURE CITED
Fordham, J. W. L., and Williame, H. Leverne, Can. J . Rcr , 27-B,943 (1949). Fordham. J. W. L., and Williams, H. Leverne, Ibid., in press Fordham, J. W. L., and Williams, H. Leverne, J . Am. C'hem. Soc., in press. Haward, R. N., J . Polymer Sci., 4,273 (1949). Horner, L., KUnSl8tOfle ver. Kunststo,f-Tech. u. Anvend., 39, 292 (1949).
Horner, L., and Schwenk, E., Angew. Chem., 61, 311 (1949). Mitchell, J. M., Spolsky, R., and Williams, H. Leverne, IND. ENG.CHEM.,41. 1692 (1949). Smith, H. S., Warner, H. C., Madigan, J. C., and Howland, L. H., Ibid., 41, 1684 (1949). Smith, W. V., J, Am. Chem. SOC.,70, 3695 (1948). Ibid., 71,4077 (1949). Smith, W. V., and Ewart, R. H., J . Chem. Phya., 16,592 (1946 . Whitby, G . S., Wellman, N., Floutz, V. W., and Stephem, H. L., IND.ENG.CHRM.,42,445, 452 (1950). RDCEIVED Maroh 10,1950. Presented before the Division of Organio ChernSOCIETY, Philadeiistry at the 117th Meeting of the AAIlPBICAN CHEMICAL phis, Pa.
