Patent · US Expired

Procedure for manufacturing transparent, impact-resistant styrene resin

US5234998A · kind A · utility

1Cited by
4References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 29, 1991
Grant dateAug 10, 1993
Priority date
Expiry dateApr 29, 2011

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F297/04
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

A process for manufacturing block copolymers comprising anionically polymerizing a vinyl aromatic hydrocarbon mononer in solution in an aromatic hydrocarbon solvent capable of giving a homogeneous medium until attaining a homogeneous medium with a viscosity greater than 300 Pa.s at 20.degree. C. for a concentration of polymer in the aromatic hydrocarbon solvent between 60 and 90% by weight and then, after introduction of a conjugated diene, carrying out a copolymerization until a homogeneous medium is attained have a viscosity greater than 300 Pa.s at 90.degree. C. for a concentration of copolymer in the aromatic hydrocarbon solvent between 70 and 90% by weight, without the viscosity exceeding 3,000 Pa.s in either of the two polymerization steps.

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