Patent ID: 6534593
Filing Date: 2003-03-18
Classification: C08F,C08L,C09D,C09J

Abstract:
A mixture of poly(aromatic vinyl)/polyisoprene block copolymers comprising 1 to 34% by weight of a diblock polymer represented by the following General Formula 1 and referred to as component (a), 34 to 99% by weight of a four-branch polymer represented by the following General Formula 2 and referred to as component (b), and 0 to 50% by weight of at least one branched polymer selected from the group consisting of a two-branch polymer represented by the following General Formula 3 and a three-branch polymer represented by the following General Formula 4, and preferred to as component (c), wherein the poly(aromatic vinyl)/polyisoprene block copolymer composed of component (a), component (b) and component (c) and contained in the poly(aromatic vinyl)/polyisoprene block copolymer composition has a weight-average molecular weight (Mw) of 260,000 to 500,000, and the poly(aromatic vinyl)/polyisoprene block copolymer composed of component (a), component (b) and component (c) and contained in the poly(aromatic vinyl)/polyisoprene block copolymer composition has a poly(aromatic vinyl) block content of 5 to 24% by weight:A1-B1â€ƒâ€ƒGeneral Formula 1: wherein A1 is a poly(aromatic vinyl) block having a weight-average molecular weight (Mw) of 9,000 to 20,000, and B1 is a polyisoprene block;(A2-B2)4X2â€ƒâ€ƒGeneral Formula 2: wherein A2 is a poly(aromatic vinyl) block having a weight-average molecular weight (Mw) of 9,000 to 20,000, B2 is a polyisoprene block, and X2 is a residue of a coupling agent having a functionality of 4 or higher;(A3-B3)2X3â€ƒâ€ƒGeneral Formula 3: wherein A3 is a poly(aromatic vinyl) block, B3 is a polyisoprene block, and X3 is a residue of a coupling agent having a functionality of 2 or higher;(A4-B4)3X4â€ƒâ€ƒGeneral Formula 4: wherein A4 is a poly(aromatic vinyl) block, B4 is a polyisoprene block, and X4 is a residue of a coupling agent having a functionality of 3 or higher, with the proviso that the amount of the two-branch polymer is not greater than 10% by weight.