Patent · US Expired

Process for preparing a microporous membrane and such a membrane

US5076925A · kind A · utility

100Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 1990
Grant dateDec 31, 1991
Priority date
Expiry dateApr 17, 2010

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D2325/36
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention relates to a process for preparing a microporous membrane, starting from a mixture of at least a hydrophobic polymer and a hydrophilic polymer, by dissolving these polymers first in a suitable solvent or mixture of solvents and subsequently by coagulating in a coagulation bath. According to the invention a more or less hydrophilic membrane is prepared by removing the membrane so obtained from the coagulation bath and subsequently by leaching at least a part of the hydrophilic polymer from the matrix, alternatively followed by hydrophobization. Said leaching of the hydrophilic polymer occurs by treatment of the membrane with an oxidizing/hydrolizing agent. The invention furthermore comprises microporous membranes, flat or tubular or in the form of hollow fibers, having a good chemical resistance and good mechanical strength.

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