Elastomeric propylene-ethylene-diene terpolymer compositions

Patent metadata

Field	Value
Publication number	US-11053381-B2
Application number	US-201816499684-A
Country	US
Kind code	B2
Filing date	Feb 6, 2018
Priority date	Apr 14, 2017
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

In some embodiments, the present disclosure provides a composition comprising from 5 phr to 30 phr of a PEDM terpolymer having 1 to 10 wt % diene, 13 to 40 wt % ethylene, and 15 to 85 wt % propylene, based on the weight of the PEDM terpolymer. The composition further comprises from 70 phr to 95 phr of an ethylene-based copolymer comprising an ethylene content different than the first polymer, a C 3 to C 12 α-olefin, and, optionally, one or more dienes.

First claim

We claim:

1. A composition comprising:
from 5 to 30 parts by weight per hundred parts by weight rubber (phr) of a propylene-α-olefin-diene (PEDM) terpolymer comprising 1 to 10 wt % diene, 13 to 40 wt % α-olefin, and 15 to 85 wt % propylene, said wt % based on the weight of the PEDM terpolymer; and
from 70 to 95 phr of an ethylene-based copolymer comprising ethylene, one or more C 3 to C 12 α-olefins, and, optionally, one or more dienes; wherein the amount of ethylene content of the ethylene-based copolymer (in wt % on the basis of total weight of the ethylene-based copolymer) is different from the amount of α-olefin content of the PEDM terpolymer (in wt % on the basis of total weight of the PEDM terpolymer).

2. The composition of claim 1 , wherein the PEDM is formed by polymerizing propylene, one or more α-olefins, and one or more dienes in the presence of a bridged fluorenyl-cyclopentadienyl group 4 catalyst that has been activated by an activator;
wherein the catalyst is represented by Formula (I):

wherein J is a divalent bridging group;
M is a group 4 transition metal;
each X is independently a univalent anionic ligand, or two Xs are joined together to form a metallocycle ring with M, or two Xs are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand;
each R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10 is independently hydrogen, C 1 to C 50 substituted or unsubstituted alkyl, provided that any one or more of the pairs R 1 and R 2 , R 3 and R 4 , R 5 and R 6 , R 6 and R 7 , R 8 and R 9 , and R 9 and R 10 , may optionally be bonded together to form a saturated or partially saturated cyclic or fused ring structure; and
the activator is a non-coordinating anion activator.

3. The composition of claim 2 , wherein the bridged fluorenyl-cyclopentadienyl group 4 catalyst is 1,1′-bis(4-triethylsilylphenyl)methylene(cyclopentadienyl)(2,7-di-tertiary-butyl-fluoren-9-yl)hafnium dimethyl.

4. The composition of claim 2 , wherein the activator is N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate.

5. The composition of claim 1 , wherein the PEDM terpolymer has a H f less than 1 J/g.

6. The composition of claim 1 , wherein the PEDM terpolymer has a crystallinity of from 0.1% to 5%, as determined by differential scanning calorimetry.

7. The composition of claim 1 , wherein the PEDM terpolymer has atactic propylene sequences.

8. The composition of claim 1 , wherein the PEDM terpolymer has an α-olefin that is ethylene and an ethylene content from 30 wt % to 40 wt %.

9. The composition of claim 1 , wherein the diene of the PEDM terpolymer is one or more of 5-ethylidene-2-norbornene, dicyclopentadiene, 5-vinyl-2-norbornene, 1,4-hexadiene, alkyldicyclopentadiene, 1,4-pentadiene, 1,5-hexadiene, 1,4-heptadiene, 2-methyl-1,5-hexadiene, cyclooctadiene, 1,4-octadiene, 1,7-octadiene, 5-n-propylidene-2-norbornene, 5-(2-methyl-2-butenyl)-2-norborene, and norbornadiene.

10. The composition of claim 9 , wherein the diene of the PEDM terpolymer is 5-ethylidene-2-norbornene.

11. The composition of claim 1 , wherein the PEDM terpolymer has a diene content from 2 wt % to 4 wt %.

12. The composition of claim 1 , wherein the ethylene-based copolymer comprises 40 to 95 wt % ethylene, 0 to 10 wt % of one or more dienes, and a C 3 to C 12 α-olefin, said wt % s based on the total weight of the ethylene-based copolymer.

13. The composition of claim 1 , wherein the C 3 to C 12 α-olefin of the ethylene-based copolymer is propylene or 1-butene.

14. The composition of claim 1 , wherein the C 3 to C 12 α-olefin of the ethylene-based copolymer is propylene.

15. An at least partially cross-linked elastomeric composition that is the reaction product of:
a composition according to claim 1 ;
one or more vulcanization activators; and
one or more vulcanizing agents.

16. The composition of claim 15 , further comprising one or more additives comprising at least one of carbon black and/or process oil.

17. The composition of claim 16 , wherein the composition comprises from 1 phr to 150 phr of a paraffinic process oil, the paraffinic process oil having a viscosity at 40° C. within the range from 80 to 600 CSt.

18. The composition of claim 16 , further comprising a mineral filler.

19. The composition of claim 15 , wherein the composition has a tack of about 4,000 Pa or greater and a green strength 25% modulus of about 1.7 MPa or greater.

20. The composition of claim 15 , wherein the composition has a tensile strength at break of 21.4 MPa or greater.

21. The composition of claim 15 , wherein the composition has a tack of at least about 3.4 kPa.

22. The composition of claim 21 , wherein the composition has a tack of at least about 5.5 kPa.

23. A transmission belt, comprising:
a composition according to claim 1 .

24. The transmission belt of claim 23 , further comprising at least one of a filler, a plasticizer, or a stabilizer.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Dharmarajan Narayanaswami
• Walker Ron
• Loyd Scott H

Classifications

• C08F2420/10

  Heteroatom-substituted bridge, i.e. Cp or analog where the bridge linking the two Cps or analogs is substituted by at least one group that contains a heteroatom · CPC title

• C08F210/16

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• F16G1/06

  made of rubber (F16G1/28 takes precedence {; consisting of several parts F16G1/22}; making thereof B29D29/00 ) · CPC title

• F16G5/10

  with metal reinforcement · CPC title

• F16G1/10

  with textile reinforcement · CPC title