Composition based on natural rubber and a polyimine compound

Patent metadata

Field	Value
Publication number	US-9566828-B2
Application number	US-201013383179-A
Country	US
Kind code	B2
Filing date	Jul 8, 2010
Priority date	Jul 10, 2009
Publication date	Feb 14, 2017
Grant date	Feb 14, 2017

Abstract

Reinforced rubber composition based on, exhibiting a lesser hysteresis degradation over time, based on at least (a) an elastomeric matrix predominantly based on natural rubber, (b) a reinforcing filler and (c) a specific polyimine compound in a content of between 6 and 20 mmol per 100 g of elastomer. This rubber composition is intended, for example, for the manufacture of a semi-finished rubber product intended for the tyres of motor vehicles.

First claim

The invention claimed is:

1. A rubber composition based at least:
(a) on an elastomeric matrix comprising non-halogenated natural rubber, wherein the weight fraction of natural rubber in the elastomeric matrix is greater than or equal to 50% by weight of the total weight of the matrix,
(b) on a reinforcing filler, and
(c) on a polyimine compound, in a proportion ranging from 6 to 20 mmol per 100 g of elastomer, wherein the polyimine compound is selected from the group consisting of N,N′-bis(4-methylpentan -2-ylidene)hexane-1,6-diamine, N,N′-bis(2,6-dimethylheptan-4-ylidene)hexane-1,6-diamine, N,N′-bis(2,4-dimethylpentan-3-ylidene)hexane-1,6-diamine, N,N′-bis(4-methylpentan-2-ylidene)octane-1,8-diamine, N,N′-bis(2,6-dimethylheptan-4-ylidene)octane-1,8-diamine, N,N′-bis(2,4-dimethylpentan-3-ylidene)octane-1,8-diamine, N,N′-dicyclopentylidenehexane-1,6-diamine, N,N′-dicyclopentylideneoctane-1,8-diamine, N,N′-dicyclohexylidenehexane -1,6-diamine, N,N′-dicyclohexylideneoctane-1,8-diamine, N,N′-bis(4-methylpentan-2-ylidene)cyclohexane-1,4-diamine, N,N′-bis(4-methylpentan-2-ylidene)cyclohexane-1,2-diamine, N,N′-bis(2,6-dimethylheptan-4-ylidene)cyclohexane-1,4-diamine, N,N′-bis(2,6-dimethylheptan-4-ylidene)cyclohexane-1,2-diamine, N,N′-dicyclohexylidenecyclohexane-1,4-diamine, N,N′-dicyclohexylidenecyclohexane-1,2-diamine, N-(4-methylpentan-2-ylidene)-,N′,N′-bis((4-methylpentan-2-ylideneamino)ethyl)ethane-1,2-diamine and N-(2,6-dimethylheptan-4-ylidene)-N′,N′-bis(2-(2,6-dimethylheptan-4-ylideneamino) ethyl)ethane-1,2-diamine.

2. A rubber composition according to claim 1 , wherein the elastomeric matrix consists of 100% natural rubber.

3. A rubber composition according to claim 1 , wherein the reinforcing filler comprises an organic filler in a proportion of 100% by weight of the total weight of the filler.

4. A rubber composition according to claim 3 , wherein the organic filler is carbon black.

5. A rubber composition according to claim 1 , wherein the reinforcing filler comprises an inorganic filler and wherein it also comprises a coupling agent.

6. A rubber composition according to claim 5 , wherein the inorganic filler is a reinforcing silica.

7. A rubber composition according to claim 1 , wherein the reinforcing filler comprises a reinforcing inorganic filler in proportions ranging from 55% to 100% by weight of the total weight of the filler.

8. A rubber composition according to claim 1 , wherein the polyimine compound is present in a proportion ranging from 6 to 16 mmol per 100 g of elastomer.

9. A rubber composition according to claim 1 , wherein the polyimine compound is selected from the group consisting of N,N′-bis(4-methylpentan-2-ylidene)hexane-1,6-diamine; N,N′-bis(4-methylpentan-2-ylidene)cyclohexane-1,4-diamine; and N,N′-bis(4-methylpentan-2-ylidene)cyclohexane-1,2-diamine.

10. A rubber composition according to claim 1 , wherein the rubber composition includes a crosslinking system.

11. A process for the preparation of a reinforced rubber composition as described in claim 1 , comprising the following stages:
(i) carrying out, at a maximum temperature of between 130° C. and 200° C., a first step of thermomechanical working of at least the elastomeric matrix and the reinforcing filler of the rubber composition, with the exception of a crosslinking system, by incorporating, ingredients of the composition in the elastomeric matrix based on natural rubber, then
(ii) carrying out, at a temperature lower than said maximum temperature of said first step, a second step of mechanical working during which said crosslinking system is incorporated, wherein the addition of the polyimine compound is carried out during the abovementioned stage (ii).

12. A preparation process according to claim 11 , wherein the polyimine compound is added in a high content ranging from 6 to 20 mmol per 100 g of elastomer.

13. A preparation process according to claim 12 , wherein the polyimine compound is added in a proportion ranging from 6 to 16 mmol per 100 g of elastomer.

14. A process for improving, over time, the hysteresis properties of a tire, comprising the incorporation, during the manufacture of this tire, of a reinforced rubber composition prepared in accordance with claim 11 .

15. A tire semi-finished rubber product, comprising a crosslinkable or crosslinked rubber composition according to claim 1 .

16. A tire comprising a semi-finished product according to claim 15 .

Assignees

• Araujo Da Silva José Carlos
• Belz Justin
• Michelin Rech Tech
• Michelin & Cie

Inventors

• Araujo Da Silva José Carlos
• Belz Justin

Classifications

• C08L21/00

  Compositions of unspecified rubbers · CPC title

• C08K5/29

  Compounds containing {one or more} carbon-to-nitrogen double bonds · CPC title

• B60C1/0016 Primary

  Compositions of the tread · CPC title