Patent · US Expired

Process for producing microporous powders and membranes

US4968733A · kind A · utility

179Cited by
1References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 1, 1989
Grant dateNov 6, 1990
Priority date
Expiry dateSep 1, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S424/07
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process produces microporous powders or shaped articles, in particular membranes in the form of flat films, tubular films or hollow fibers, which may be used for controlled release of an active compound, for dialysis, gas separation, ultrafiltration or microfiltration, from polyvinylidene fluoride and/or polyphenylene sulfide and/or polysulfone and/or polyacrylonitrile and/or ethylene/vinyl alcohol copolymer and/or ethylene/chlorotrifluoroethylene copolymer and/or polyethersulfone and/or polyether-imide and/or polymethyl methacrylate and/or polycarbonate and/or cellulose triacetate. The process utilizes phase separation by means of thermally induced triggering or triggering induced by a non-solvent of a solution of the polymer in a mixture containing .epsilon.-caprolactam as the essential dissolving constituent. The solution may be formed before the phase separation is triggered.

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