Rubber Composition Comprising a Thiazole
A rubber composition for the manufacture of tires, based on one or more diene elastomers, on one or more reinforcing fillers and on a vulcanization system, the vulcanization system comprising one or more thiazole compounds of formula:
1 . Rubber composition for the manufacture of tires, based on one or more diene elastomers, on one or more reinforcing fillers and on a vulcanization system, characterized in that the said vulcanization system comprises one or more thiazole compounds of formula:
where
R1 and R2 independently represent H or a C 1 -C 25 -hydro-carbon group chosen from linear, branched or cyclic alkyl groups and aryl groups, optionally interrupted by one or more heteroatoms, it being possible for R1 and R2 to together form a non-aromatic ring,
R3 represents:
a linear or branched C1-C25 alkyl group which is optionally interrupted by one or more heteroatoms and which is optionally substituted by one or more cyclic C3-C10 alkyl or C6-C12 aryl groups, or
a cyclic C3-C10 alkyl group which is optionally interrupted by one or more heteroatoms and which is optionally substituted by one or more linear, branched or cyclic C1-C25 alkyl or C6-C12 aryl groups which are optionally interrupted by one or more heteroatoms.
2 . The composition according to claim 1 , wherein R1 and R2 independently represent H or a methyl group.
3 . The composition according to claim 2 , wherein R1 and R2 each represent H.
4 . The composition according to claim 2 , wherein R1 and R2 each represent a methyl group.
5 . The composition according to claim 1 , wherein R3 represents a cyclohexyl group or a tert-butyl group.
6 . The composition according to claim 1 , wherein the thiazole compound or compounds are chosen from the compounds of formula (I) in which R3 represents a cyclohexyl and:
R1 and R2 represent a methyl group, or
R1 and R2 represent H, or
R1 represents a methyl group and R2 represents H, or
R1 represents H and R2 represents a methyl group.
7 . The composition according to claim 1 , wherein the thiazole compound or compounds represent from 0.1 to 10 phr (parts by weight per hundred of diene elastomer).
8 . The composition according to claim 1 , wherein the diene elastomer or elastomers are chosen from the group consisting of polybutadienes, natural rubber, synthetic polyisoprenes, butadiene copolymers, isoprene copolymers and the mixtures of these elastomers.
9 . The composition according to claim 8 , wherein the diene elastomer is natural rubber or a blend of natural rubber with a polybutadiene or a butadiene/stirene copolymer.
10 . The composition according to claim 1 , wherein the reinforcing filler or fillers are chosen from silica, carbon black and their mixtures.
11 . The composition according to claim 1 , wherein the reinforcing filler or fillers are present at a level of between 20 and 200 phr.
12 . Process for preparing a rubber composition for the manufacture of tires as defined in claim 1 , comprising the steps of:
incorporating the reinforcing filler or fillers in the diene elastomer or elastomers, during a first “non-productive” stage, everything being kneaded thermomechanically, in one or more goes, until a maximum temperature of between 130° C. and 200° C. is reached,
cooling the combined mixture to a temperature of less than 100° C.,
subsequently incorporating, during a second “productive” stage, the vulcanization system and then
kneading everything up to a maximum temperature of less than 120° C.
13 . Use of a composition according to claim 1 in the manufacture of a finished article or a semi-finished product intended for a motor vehicle ground-contact system.
14 . Finished article or semi-finished product intended for a motor vehicle ground-contact system, comprising a composition according to claim 1 .
15 . Tire, comprising a rubber composition as defined in claim 1 .
16 . Use as vulcanization accelerator, in a composition based on one or more diene elastomers, on one or more reinforcing fillers and on a vulcanization system, of one or more thiazole compounds of formula (I) as defined in claim 1 .
17 . The composition according to claim 1 , wherein the thiazole compound or compounds represent from 0.5 to 7 phr (parts by weight per hundred of diene elastomer).
18 . The composition according to claim 1 , wherein the thiazole compound or compounds represent from 0.5 to 5 phr (parts by weight per hundred of diene elastomer).
19 . The composition according to claim 1 , wherein the reinforcing filler or fillers are present at a level of between 30 and 150 phr.