INDUSTRIAL AND ENGINEERING CHEMISTRY
2742
TABLEVI.
GR-S
Compound Ethylene glycol Ethylene glycol Formarnide Acetic acid" Pyridine= Anhydrous ammoniaa
OTHER
~ O L Y M E R I Z A T I O h ' IS
MEDIA
Time, Hours 432 44 168 25 112
15
Temperature,
c.
hHYDROLTS
Monomer Conversion
Catalyst
Xone 10 25 None h-one None
K&Os h1.IDh-b AIBNC AIBNC AIBNO hlDNb
45 64 45 45 45 - 18
TABLE VII. VCLCA~IZATE PROPERTIES OF GR-S PREPARED IN TYATER-DILUEST MIXTURES
Diluent Reaction time, hours Hydrocarbon conversion, %
h-one 15 76
Ultimate tensile, lb./sq. i n 25 min. 50 min. 90 min. Average Elongation, 70 25 min. 50 min. 90 min. Resilience, % Room temp. 2120 F.
Ethylene Glycol 20 78
Glycerol 18 74
Methanol 30 76
59 74
io 72
60 67
68 79
370 820 1110
480 960 1300
400 850 1170
400 870 1270
1870 3140 3150 2720
1720 2660 2850 2410
1870 2760 3210 2570
1660 3040 3260 2660
805
650 580 500
765 645 585
715 645 555
43 48
43 46
44 47
700 573 43 47
A number of other organic compounds which were found to be insoluble in butadiene were tried in nonaqueous systems. Results are summarized in Table VI. POLYMER PROPERTIES POLYJIERS BREP4RED 4T 45' c. I n order to determine whether the presence of diluents in the aqueous phase affects the physical properties of the polymer, GR-S was prepared a t 45' C. to 75% conversion and 50 Mooney viscosity using 54 parts of methanol, ethylene glycol, or glycerol in the water phase. These polymers mere then compounded in a tread stock recipe and cured. Physical test data on these vulcanizates showed no unusual propertief (Table VII). A number of polymers prepared in 100% glycerol to varying Mooney viecosities mere also compounded and cured in a tread stock recipe. Table 1'111 shows that the stocks prepared in glycerol exhibited abnormally high qtiffening in compounding and also cured coneideralilv more rapidly than the standard GR-S
TABLE VIII.
vVLC.4SIZATE
PROPERTIES O F GR-S PREPARED IX
100% GLYCEROL hfooney viscosity Uncompounded Compounded Modulus, 300%. lb./sq. in.: cured at 292O F. 4 5 min. 90 min. Ultimate tensile, lh./sq. in. 45 min. 90 min. Averaee
a
Standard GR-S.
Control&
Polymers Prepared in Glycerol
49 65
43 86
690 1170
1790 2030
2450 2400 2425
2040 2150 2090
690 513
340
41 43
37
320 45
62 100
..
..
79 120
..
..
1930 2130 1990 2150 1960 zjzo
86 127 2310
..
Vol. 45, No. 12
TABLEIX. VULCAXIZATE PROPERTIES OF GR-S PREPARED AT - 18' C. WITH hnr\ro;vra ASTIFREEZE Antifreeze MBTSa Mooney viscosity Uncompounded Compounded Modulus, 300%. Ib./ sq. in cured a t 2920 F. 30 min. 60 min. 90 min. Ultimate tensile, lb./sq. in. 30 min. 60 min. 90 min. Average Elongation, % ' 30 min. 60 min. rnin. 90 min. Aged tensile, aged 72 hours; 212O F. 30 min. 60 min. 90 min. Averaxe Elongation, % 30 min. 60 min. 90 min.
Methanol 1 75
Ammonia L75
Ammonia 1.0
A.mmonia 1.0
57
..
60
63 94
94 114
430 1120 1590
1260 1720 2050
400 1150 1400
830 1300 1600
3230 3970 3630 3610
3220 3610 3210 3050
2840 4060 3880 3590
3970
550 500 420
930
2430 2310 2500 2410
2450 2280 2790 2510
3200 2750 2960 2910
310 280 300
180 210 290
.
a
900 R ln 610 _.. 510
3fi80
3730 3760 720 5.50 520
700 590
2790 2830 3000
2870 3 00 310 330
Rleroaptobenzothiazoledisulfide.
control. Tensile strengths were somewhat lower than the control a t all levels of viscosity. POLYMERS PREPARED AT -18' c. Polymer was prepared at -18' C. for physical testing with both methanol and ammonia as antifreeze. Preliminary tests of the material prepared in the presence of ammonia gave overcured stocks, but by adiusting the accelerator level cure rates equivalent to the polymer prepared in methanol were obtained. Table I X summarizes the phvsical test data. -4s would be expected. the tensile strength of the low temperature polymers are considerably higher than those prppared a t 45' C. There appears to be no essential difference between the polymers prepared with methanol and with ammonia when allowance is made for the differences in cure rate. ACKNOWLEDGMENT
The work discussed herein was performed as a part of t h r research project sponsored by the Reconstruction Finanre Corp., Office of Synthetic Rubber, in connection with the Government Synthetic Rubber Program. LITERATURE CITED (1) B r o w n , R. W., p r i v a t e communication (Oct. 3, 1950). (2) C a r r , E. L., a n d J o h n s o n , P. H., IND.EXG. CHEY.. 41, 1588 (1949). (3) General T i r e & R u b b e r Po., p r i v a t e communication t o Office of S y n t h e t i c R u b b e r , Reconstruction Finance Corp. (4) I l o w l a n d , L. H.. a n d Reynolds, J. d.,pi,ivate communication ( M a y 20, 1948). ( 5 ) Kolthoff, I. AI., a n d D a l e , W.J.,J . Polymer SCL., 3 , 400 (1948) (6) St. J o h n , W.AI.. e t a l . , Ibid., 7 , 159 (1951). (7) T r o y a n , J. E., Rubbei A g e , 63, 585 (1948). (8) United S t a t e s R u b b e r Co., p r i v a t e communication to Office of S y n t h e t i c R u b b e r , Reconstruction F i n a n c e Corp. (9) W h i t b y , G. S.,Wellman, N., F l o u t s , V. W., a n d S t e p h e n s , H. I,., IND. EXG.CHEM.,42, 448 (1950). RECRIvED for review March 2 5 , 19.53.
-iCc~r"rED,Jiily 6 , 1953.
2310 1900 2100
290 285
290 275
300 260
41 52
40 51
41 50
Diazo-Initiated Polymers-Correction I n the article on '.Diazo-Initiated Polymers" [Willis, J. If., Alliger, Glen, Johnson, B. I,, and Otto, TV. M., 1x11 ENG.CHCV, 45, 1316 (195311 the patent cited in referenre (4)should h a w been 2,376,963.
