FIELD: chemical industry.
SUBSTANCE: invention relates to a modified conjugated diene based polymer as well as a rubber composition for tire or rubber products. The modified polymer based on a conjugated diene contains a functional group derived from the modified monomer of the formula
where R2 represents an alkenyl group from 2 to 10 carbon atoms, and contains a functional group derived from the modifier based on aminoalkoxysilane at least one end. The aminoalkoxysilane-based modifier is a compound of the formula
wherein Ra1 and Ra4 are each independently a single bond or an alkylene group having 1 to 10 carbon atoms, Ra2 and Ra3 are each an independent alkyl group having 1 to 10 carbon atoms, Ra5 is an alkyl a group having 1 to 10 carbon atoms, or an alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms, n1 is an integer from 1 to 3, and n2 is an integer from 0 to 2; or compound formula
wherein A1 and A2 are each an independent alkylene group having 1 to 20 carbon atoms, Rb1-Rb4 are each an independent alkyl group having 1 to 20 carbon atoms, and L1-L4 are each an independent alkylsilyl group substituted with an alkyl group having 1 to 10 carbon atoms. The modified conjugated diene polymer has a unimodal molecular weight distribution curve and a molecular weight distribution of 1.0 or more to less than 1.7.
EFFECT: resulting polymer has a narrow and unimodal molecular weight distribution and exhibits excellent tensile properties and viscoelastic properties, while also having excellent processability.
13 cl, 4 dwg, 3 tbl, 3 ex
