Processability butyl rubber and process for production thereof
View Patent ↗A butyl polymer having improved processability is described, together with a process for production thereof. The butyl polymer derived from a reaction mixture which contains: (i) a monomer mixture comprising a C4 to C7 monoolefin monomer (preferably isobutylene) and a C4 to C14 multiolefin monomer (preferably isoprene); (ii) a multiolefin cross-linking agent (preferably divinyl benzene); and (iii) a chain transfer agent (preferably diisobutylene (2,2,4-trimethyl-1-pentene)). The subject butyl polymer has an improved balance of cold flow, filler dispersion, extrusion rate and die swell.
1. A butyl polymer having improved processability, prepared with a reaction mixture comprising:
(i) a monomer mixture comprising a C 4 to C 7 monoolefin monomer and a C 4 to C 14 multiolefin monomer or β-pinene;
(ii) a multiolefin cross-linking agent; and
(iii) a chain transfer agent.
2. The butyl polymer according to claim 1 , wherein the C 4 to C 7 monoolefin monomer is selected from the group comprising isobutylene, 2-methyl-1-butane, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene and mixtures thereof.
3. The butyl polymer according to claim 2 , wherein the C 4 to C 7 monoolefin monomer comprises isobutylene.
4. The butyl polymer according to claim 1 , wherein the C 4 to C 14 multiolefin monomer is selected from the group comprising isoprene, butadiene, 2-methyl-butadiene, 2,4-dimethylbutadiene, piperyline, 3-methyl-1,3-pentadiene, 2,4-hexadiene, 2-neopentylbutadiene, 2-methyl-1,5-hexadiene, 2,5-dimethyl-2,4-hexadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,6-heptadiene, cyclopentadiene, methylcyclopentadiene, cyclohexadiene, 1-vinyl-cyclo-hexadiene and mixtures thereof.
5. The butyl polymer according to claim 4 , wherein the C 4 to C 14 multiolefin monomer comprises isoprene.
6. The butyl polymer according to claim 1 , wherein the monomer mixture comprises from about 80% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1.0% to about 20% by weight C 4 to C 14 multiolefin monomer or β-pinene.
7. The butyl polymer according to claim 6 , wherein the monomer mixture comprises from about 85% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1.0% to about 15% by weight C 4 to C 14 multiolefin monomer or β-pinene.
8. The butyl polymer according to claim 7 , wherein the monomer mixture comprises from about 95% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1% to about 5.0% by weight C 4 to C 14 multiolefin monomer or β-pinene.
9. The butyl polymer according to claim 1 , wherein the multiolefin crosslinking agent comprises a diolefinic hydrocarbon compound.
10. The butyl polymer according to claim 9 , wherein the multiolefin crosslinking agent is selected from the group comprising divinylbenzene, diisopropenylbenzene, divinyltoluene, divinylxylene and a C 1 to C 20 alkyl-substituted derivatives thereof.
11. The butyl polymer according to claim 10 , wherein the multiolefin crosslinking agent comprises divinylbenzene.
12. The butyl polymer according to claim 1 , wherein the multiolefin crosslinking agent is present in the reaction mixture in an amount in the range of from about 0.01% to about 3.0% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
13. The butyl polymer according to claim 12 , wherein the multiolefin crosslinking agent as present in the reaction mixture in an amount in the range of from about 0.05% to about 1.0% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
14. The butyl polymer according to claim 13 , wherein the multiolefin crosslinking agent as present in the reaction mixture in an amount in the range of from about 0.1% to about 0.4% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
15. The butyl polymer according to claim 1 , wherein the chain transfer agent is selected from the group comprising piperylene, 1-methylcycloheptene, 1-methylcyclo-pentene, 2-ethyl-1-hexene, 2,4,4-trimethyl-1-pentene, indene and mixtures thereof.
16. The butyl polymer according to claim 15 , wherein the chain transfer agent comprises 2,4,4-trimethyl-1-pentene.
17. The butyl polymer according to claim 1 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about 0.01% to about 2.0% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
18. The butyl polymer according to claim 17 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about0.01% to about 1.4% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
19. The butyl polymer according to claim 18 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about 0.05% to about 0.5% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
20. The butyl polymer according to claim 1 , wherein the polymer comprises a halogenated butyl polymer.
21. The butyl polymer according to claim 20 , wherein the polymer is brominated.
22. The butyl polymer according to claim 20 , wherein the polymer is chlorinated.
23. The butyl polymer according to claim 20 , wherein the amount of halogen is in the range of from about 0.1 to about 8% by weight of the polymer.
24. The butyl polymer according to claim 23 , wherein the amount of halogen is in the range of from about 0.5 to about 4% by weight of the polymer.
25. The butyl polymer according to claim 24 , wherein the amount of halogen is in the range of from about 1.5 to about 3% by weight of the polymer.
26. A process for preparing a butyl polymer having improved processability, comprising the step of continuing a reaction mixture comprising:
(i) a monomer mixture comprising a C 4 to C 7 monoolefin monomer and a C 4 to C 14 multiolefin monomer or β-pinene;
(ii) a multiolefin cross-linking agent;
(iii) a chain transfer agent; and
(iv) a catalyst system.
27. The process according to claim 26 , wherein the C 4 to C 7 monoolefin monomer is selected from group comprising isobutylene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, 4-methyl-1-pentene, and mixtures thereof.
28. The process according to claim 26 , wherein the C 4 to C 7 monoolefin monomer comprises isobutylene.
29. The process according to claim 26 , wherein the C 4 to C 14 multiolefin monomer is selected from the group comprising isoprene, butadiene, 2-methylbutadiene, 2,4-dimethylbutadiene, piperyline, 3-methyl-1,3-pentadiene, 2,4-hexadiene, 2-neopentylbutadiene, 2-methyl-1,5-hexadiene, 2,5-dimethyl-2,4-hexadiene, 2-methyl-1,4-pentadiene, 2-methyl-1,6-heptadiene, cyclopentadiene, methylcyclopentadiene, cyclohexadiene, 1-vinyl-cyclo-hexadiene and mixtures thereof.
30. The process according to claim 29 , wherein the C 4 to C 14 multiolefin monomer comprises isoprene.
31. The butyl polymer according to claim 26 , wherein the monomer mixture comprises from about 80% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1.0% to about 20% by weight C 4 to C 14 multiolefin monomer or β-pinene.
32. The butyl polymer according to claim 31 , wherein the monomer mixture comprises from about 85% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1.0% to about 15% by weight C 4 to C 14 multiolefin monomer or β-pinene.
33. The butyl polymer according to claim 32 , wherein the monomer mixture comprises from about 95% to about 99% by weight C 4 to C 7 monoolefin monomer and from about 1% to about 5.0% by weight C 4 to C 14 multiolefin monomer or β-pinene.
34. The process according to claim 26 , wherein the multiolefin crosslinking agent comprises a diolefinic hydrocarbon compound.
35. The process according to claim 34 , wherein the multiolefin crosslinking agent is selected from the group comprising divinylbenzene, diisopropenylbenzene, divinyltoluene, divinylxylene and a C 1 to C 20 alkyl-substituted derivatives thereof.
36. The process according to claim 35 , wherein the multiolefin crosslinking agent comprises divinyl-benzene.
37. The process according to claim 26 , wherein the multiolefin crosslinking agent is present in the reaction mixture in an amount in the range of from about 0.01% to about 3.0% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
38. The process according to claim 37 , wherein the multiolefin crosslinking agent is present in the reaction mixture in an amount in the range of from about 0.05% to about 1.0% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
39. The process according to claim 38 , wherein the multiolefin crosslinking agent is present in the reaction mixture in an amount in the range of from about 0.1% to about 0.4% by weight based on the amount of the C 4 to C 7 monoolefin monomer in the monomer mixture.
40. The butyl polymer according to claim 26 , wherein the chain transfer agent is selected from the group comprising piperylene, 1-methylcycloheptene, 1-methylcyclopentene, 2-ethyl-1-hexene, 2,4,4-trimethyl-1-pentene, indene and mixtures thereof.
41. The process according to claim 40 , wherein the chain transfer agent comprises 2,4,4trimethyl-1-pentene.
42. The process according to claim 26 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about 0.01% to about 2.0% by weight based on the amount of th C 4 to C 7 monoolefin monomer in the monomer mixture.
43. The process according to claim 42 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about 0.05% to about 1.4% by weight based on the amount of th C 4 to C 7 monoolefin monomer in the monomer mixture.
44. The process according to claim 43 , wherein the chain transfer agent is present in the reaction mixture in an amount in the range of from about 0.1% to about 0.5% by weight based on the amount of th C 4 to C 7 monoolefin monomer in the monomer mixture.