Patent ID: 7960481

Claim:
A second-order modified, hydrogenated copolymer obtained: by reacting a first-order modified, hydrogenated copolymer with a second-order modifier, said first-order modified, hydrogenated copolymer comprising a hydrogenated copolymer and a functional group-containing first-order modifier group bonded to said hydrogenated copolymer, said second-order modifier having a functional group which is reactive to said functional group of said first-order modifier group of said first-order modified, hydrogenated copolymer, said hydrogenated copolymer being obtained by hydrogenating an unhydrogenated copolymer comprising conjugated diene monomer units and vinyl aromatic monomer units, said hydrogenated copolymer comprising: at least one polymer block selected from the group consisting of a polymer block (A) of vinyl aromatic monomer units, and a hydrogenated polymer block (C) which is obtained by hydrogenating an unhydrogenated polymer block of conjugated diene monomer units, said unhydrogenated polymer block of conjugated diene monomer units having a vinyl bond content of less than 30%, and at least one hydrogenated copolymer block (B) which is obtained by hydrogenating an unhydrogenated random copolymer block comprised of conjugated diene monomer units and vinyl aromatic monomer units, said unhydrogenated random copolymer block having a vinyl bond content of 60% or less as measured with respect to the conjugated diene monomer units in said unhydrogenated random copolymer block, wherein, when said hydrogenated copolymer contains no hydrogenated polymer block (C), said hydrogenated copolymer contains at least two polymer blocks (A), said hydrogenated copolymer having the following characteristics (1) to (6): (1) said hydrogenated copolymer has a content of said vinyl aromatic monomer units of from more than 40% by weight to less than 95% by weight, based on the weight of said hydrogenated copolymer, (2) said hydrogenated copolymer has a content of said polymer block (A) of 0 to 60% by weight, based on the weight of said hydrogenated copolymer, (3) said hydrogenated copolymer has a weight average molecular weight of from 30,000 to 1,000,000, (4) said hydrogenated copolymer has a hydrogenation ratio of 75% or more, as measured with respect to the double bonds in said conjugated diene monomer units, (5) at least one peak of loss tangent (tan δ) is observed at −10 to 80° C. in a dynamic viscoelastic spectrum obtained with respect to said hydrogenated copolymer, and (6) when said hydrogenated copolymer contains no hydrogenated polymer block (C), substantially no crystallization peak ascribed to said at least one hydrogenated copolymer block (B) is observed at −20 to 80° C. in a differential scanning calorimetry (DSC) chart obtained with respect to said hydrogenated copolymer.