Rubber composition comprising a specific crumb rubber

Patent metadata

Field	Value
Publication number	US-11028254-B2
Application number	US-201716471610-A
Country	US
Kind code	B2
Filing date	Dec 19, 2017
Priority date	Dec 20, 2016
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

A rubber composition is based on at least an elastomer, a reinforcing filler and a crosslinking system and a crumb rubber, said crumb having an isoprene elastomer content of greater than 50 phr in the composition of the crumb and a chloroform extract with a weight-average molecular weight of less than 10 000 g/mol.

First claim

The invention claimed is:

1. A rubber composition based on at least an elastomer, a reinforcing filler, a crosslinking system, and a crumb rubber,
wherein the crumb rubber has an isoprene elastomer content of greater than 50 phr in the composition of the rubber crumb and a chloroform extract with a weight-average molecular weight of less than 10,000 g/mol.

2. The rubber composition according to claim 1 , wherein the crumb rubber has an isoprene elastomer content within a range extending from 60 to 100 phr.

3. The rubber composition according to claim 1 , wherein the isoprene elastomer in the crumb rubber is selected from the group consisting of synthetic polyisoprenes, natural rubbers and mixtures thereof.

4. The rubber composition according to claim 1 , wherein the isoprene elastomer in the crumb rubber is a natural rubber.

5. The rubber composition according to claim 1 , wherein the crumb rubber is present in a content ranging from 5% to 40% by weight.

6. The rubber composition according to claim 1 , wherein the crumb rubber is present in a content ranging from 5 to 100 phr.

7. The rubber composition according to claim 1 , wherein the crumb rubber has an acetone extract of between 3% and 30% by weight.

8. The rubber composition according to claim 1 , wherein the crumb rubber has a chloroform extract of between 5% and 85% by weight.

9. The rubber composition according to claim 1 , wherein the crumb rubber has not undergone any modification by a process selected from the group consisting of thermal, mechanical, biological, and chemical treatments and combinations thereof.

10. The rubber composition according to claim 9 , wherein the crumb rubber has an acetone extract of between 3% and 15% by weight.

11. The rubber composition according to claim 9 , wherein the crumb rubber has a chloroform extract of between 3% and 20% by weight.

12. The rubber composition according to claim 9 , wherein the crumb rubber has a ratio of a chloroform extract to an acetone extract, expressed as weight percentage, of less than 1.5.

13. The rubber composition according to claim 9 , wherein the crumb rubber has a chloroform extract with a weight-average molecular weight of less than 8000 g/mol.

14. The rubber composition according to claim 1 , wherein the crumb rubber has an average particle size D50 of between 10 and 400 μm.

15. The rubber composition according to claim 1 , wherein the crumb rubber has a carbon black weight fraction ranging from 20% to 40%.

16. The rubber composition according to claim 1 , wherein the elastomer predominantly comprises an elastomer selected from the group consisting of essentially unsaturated diene elastomers.

17. The rubber composition according to claim 16 , wherein the predominant elastomer is selected from the group consisting of polybutadienes, polyisoprenes, butadiene copolymers, isoprene copolymers and mixtures thereof.

18. The rubber composition according to claim 17 , wherein the predominant elastomer is selected from the group consisting of polybutadienes, polyisoprenes and mixtures thereof.

19. The rubber composition according to claim 1 , wherein the reinforcing filler is selected from the group consisting of silicas, carbon blacks, and mixtures thereof.

20. The rubber composition according to claim 1 , wherein a content of reinforcing filler is within a range extending from 5 to 200 phr.

21. The rubber composition according to claim 1 , wherein a predominant reinforcing filler is carbon black in a content within a range extending from 30 to 90 phr.

22. The rubber composition according to claim 1 , wherein a predominant reinforcing filler is silica in a content within a range extending from 30 to 90 phr.

23. A tire comprising the rubber composition according to claim 1 .

24. The tire according to claim 23 , wherein the rubber composition constitutes all or part of a tread of the tire.

Assignees

• Michelin & Cie

Inventors

• Thomasson Damien
• Cuscito Olivia

Classifications

• C08K5/47

  Thiazoles · CPC title

• C08K5/18

  with aromatically bound amino groups · CPC title

• C08K3/36

  Silica · CPC title

• C08L7/00 Primary

  Compositions of natural rubber · CPC title

• C08L19/003 Primary

  Precrosslinked rubber; Scrap rubber; Used vulcanised rubber · CPC title