Patent ID: 8030406
Filing Date: 2011-10-04
Classification: B60C,C08C,C08L,Y10T

Abstract:
1. A rubber composition comprising 2 to 60 parts by mass of a low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) based on 100 parts by mass of a rubber component (A) composed of at least one of natural rubber and synthetic diene-based rubbers, wherein the low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) has an aromatic vinyl compound content of 5 to 80% by mass, a vinyl bond content in a conjugated diene compound portion of 5 to 80% by mass, a weight average molecular weight as measured through a gel permeation chromatography and converted to polystyrene of 5,000 to 500,000 and at least one functional group, the low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) is formed through a modification with a tin-containing compound, a silicon-containing compound or a nitrogen-containing compound, the functional group of the low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) is a tin-containing functional group, a silicon-containing functional group or a nitrogen-containing functional group, in which the nitrogen-containing functional group is at least one selected from the group consisting of a substituted or unsubstituted amino group, imino group, imidazole group, nitrile group and pyridyl group, the low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) has a weight average molecular weight as measured through a gel permeation chromatography before introduced with the functional group and converted to polystyrene of 50,000 to 150,000, and the conjugated diene compound in the low-molecular weight aromatic vinyl compound-conjugated diene compound copolymer (B) is 1,3-butadiene or isoprene.