Patent · US Expired

Polyaryl ether sulfone semipermeable membrane and process for producing same

US4286015A · kind A · utility

38Cited by
8References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 1, 1979
Grant dateAug 25, 1981
Priority date
Expiry dateMay 1, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31533
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A semipermeable membrane made of a polyaryl ether sulfone comprised of recurring units represented by the general formula (I): ##STR1## wherein X, X', X" and X"' are non-dissociative substituents, and l, m, n and o are integers of from 0 to 4. The membrane, which is composed of a single continuous polymer phase, has pores of a diameter increasing progressively and continuously from the surface layers to the center portion thereof. The membrane is prepared by the process wherein: PA1 the polyaryl ether sulfone is dissolved in a mixed solution to form a dope of the polyaryl ether sulfone; PA1 the polyaryl ether sulfone dope is extruded to form a fiber or film and, then; PA1 both sides of the fiber or film are contacted with a liquid miscible with the mixed solvent but incapable of dissolving the polyaryl ether sulfone to remove substantially all the mixed solvent from the fiber or film.

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