Patent · US Expired

Block copolymer composition, process for producing the same, and pressure-sensitive adhesive composition

US6534593B1 · kind B1 · utility

15Cited by
6References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 1, 2001
Grant dateMar 18, 2003
Priority date
Expiry dateFeb 1, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08L2666/24
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

The present invention provides a composition which comprises a radial poly(aromatic vinyl)/polyisoprene block copolymer as a major component and which can be used as a more excellent pressure-sensitive ingredient. This composition is obtained by reacting a diblock polymer with a coupling agent having a functionality of 4 or higher in the presence of a coupling accelerator, and it contains (a) 1 to 34% by weight of a diblock polymer, (b) 34 to 99% by weight of a four-branch polymer, and (c) 0 to 50% by weight of a two-branch polymer and/or a three-branch polymer. The poly(aromatic vinyl)/polyisoprene block copolymer contained in the composition has a weight-average molecular weight (Mw) of 260,000 to 500,000, and the poly(aromatic vinyl)/polyisoprene block copolymer has a poly(aromatic vinyl) block content of 5 to 24% by weight.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.