Patent · US Expired

Cyclic polyester oligomer and method for their preparation

US4829144A · kind A · utility

37Cited by
1References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 1, 1988
Grant dateMay 9, 1989
Priority date
Expiry dateFeb 1, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G63/19
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Cyclic polyester and especially polyarylate oligomers, typically having degrees of polymerization from 2 to about 7, are prepared by reacting a bisphenol such as bisphenol A or 6,6'-dihydroxy-3,3,3',3'-tetramethylspiro-(bis)indane with a dicarboxylic acid chloride such as isophthaloyl or terephthaloyl chloride in the presence of a catalyst, under conditions of low concentration. The cyclic oligomers may be polymerized to linear polyesters by contact with a transesterification catalyst at a temperature in the range of about 200.degree.-300.degree. C.

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