PROCESS FOR PREPARING A STATISTICAL COPOLYMER BASED ON ACYCLIC DIENE MONOMERS AND CYCLIC DIENE MONOMERS, COPOLYMERS AND COMPOSITIONS CONTAINING SAME

• US 20200131292A1
• Filed: 06/28/2018
• Published: 04/30/2020
• Est. Priority Date: 06/30/2017
• Status: Active Grant

• Current Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Original Assignee: Compagnie Generale DES Etablissements Michelin SCA
• Inventors: MATMOUR, Rachid, NGO, Robert, SCHNELL, Benoit
• Granted Patent: US 11,180,596 B2
• Time in Patent Office: Days
• CPC Class Codes: B60C 1/00 Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition
• CPC Class Codes: C07C 11/107 with six carbon atoms
• CPC Class Codes: C07C 11/12 Alkadienes
• CPC Class Codes: C08F 2/26 anionic
• CPC Class Codes: C08F 232/06 having two or more carbon-to-carbon double bonds
• CPC Class Codes: C08F 236/045 conjugated hydrocarbons other than butadiene or isoprene
• CPC Class Codes: C08F 236/06 Butadiene
• CPC Class Codes: C08F 236/08 Isoprene
• CPC Class Codes: C08F 236/10 with vinyl-aromatic monomers
• CPC Class Codes: C08F 2800/10 as molar percentages
• CPC Class Codes: C08F 2800/20 as weight or mass percentages

Abstract

A process for preparing a random copolymer based on at least one acyclic diene monomers and on at least one cyclic diene monomer is provided. The process comprises a step of copolymerization, in the presence of a polar agent and an anionic initiator in a polymerization solvent, of at least one acyclic diene monomer and of at least one cyclic diene monomer of which one C═C double bond is endocyclic and conjugated to an exocyclic C═C double bond, at a polymerization temperature below 80° C. A molar ratio of the polar agent/function(s) of the anionic initiator capable of initiating anionic polymrization being greater than 0.1.

Copolymers based on at least one acyclic diene monomer and on at least one cyclic diene monomer and the compositions containing them are also provided.

Claims

1. A process for preparing a random copolymer based on at least one acyclic diene monomer and on at least one cyclic diene monomer, wherein the process comprises a step of copolymerization, in the presence of a polar agent and an anionic initiator in a polymerization solvent, of at least one acyclic diene monomer and of at least one cyclic diene monomer of which one C═

C double bond is endocyclic and conjugated to an exocyclic C═

C double bond, at a polymerization temperature below 80°

C., and a molar ratio of the polar agent/function(s) of the anionic initiator capable of initiating anionic polymerization being greater than 0.1.

2. A process according to claim 1, wherein the molar ratio is greater than or equal to 0.3.

3. A process according to claim 1, wherein the at least one acyclic diene monomer includes a conjugated diene monomer.

4. A process according to claim 1, wherein the at least one cyclic diene monomer includes a monomer corresponding to the following formula (I):

where n=0 or 1

5. A process according to claim 1, wherein a vinylaromatic compound having from 8 to 20 carbon atoms is also copolymerized.

6. A process according to claim 1, wherein the polar agent is a tetraalkyldiamine.

7. A process according to claim 1, wherein the anionic initiator contains an alkali metal.

8. A process according to claim 1, wherein the polymerization temperature varies from 45°

C. to 70°

C.

15. A copolymer capable of being obtained by the process defined according to claim 1.

9. A random copolymer comprising, randomly distributed within a main linear chain of the copolymer, unsaturated units derived from at least one acyclic diene monomer and cyclic units derived from at least one cyclic diene monomer of which one C═

C double bond is endocyclic and conjugated to an exocyclic C═

C double bond.

10. A copolymer according to claim 9, wherein the acyclic diene monomer is a conjugated diene monomer.

11. A copolymer according to claim 9, wherein the cyclic diene monomer is a monomer corresponding to the following formula (I):

12. A copolymer according to claim 9, wherein the copolymer also comprises units derived from a vinylaromatic compound having from 8 to 20 carbon atoms.

13. A copolymer according to claim 9, wherein the molar percentage of units derived from the cyclic diene monomer, relative to the total number of units, is at least 5%.

14. A copolymer according to claim 9, wherein the molar percentage of units derived from the cyclic diene monomer, relative to the total number of units, is less than 50%.

16. A copolymer according to claim 9, wherein said copolymer is an elastomer.

17. A composition comprising the copolymer defined according to claim 9.

18. A tire, of which one of its constituent elements comprises a composition according to claim 17.

19. A copolymer according to claim 10, wherein the acyclic diene monomer is 1,3-butadiene or isoprene.

20. A copolymer according to claim 11, wherein the cyclic diene monomer is 3-methylenecyclopentene.