Patent · US Expired

Closed cell polyimides

US4319000A · kind A · utility

29Cited by
7References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 30, 1981
Grant dateMar 9, 1982
Priority date—
Expiry dateMar 30, 2001

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2379/08
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Closed cell polyimide foams. Methods of making such foams from precursors derived from a benzophenonetetracarboxylic acid diester and a mixture of diamines in which the precursor is molded to shape and cured, hydrated, and heated until a porous, closed cell structure develops.

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