Patent · US Expired

Semipermeable composite membranes

US5049282A · kind A · utility

48Cited by
1References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 11, 1990
Grant dateSep 17, 1991
Priority date
Expiry dateApr 11, 2010

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D2323/30
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Semipermeable composite membranes composed of a porous substrate and at least two layers of film-forming polymers coated thereon are provided, which comprise a first layer of monomeric or polymeric diazonium salts, which have been reacted with themselves and with an at least difunctional compound, and a second layer, which is chemically bonded to the first one, of a cross-linked, ionically charged hydrophilic polymer. The membranes show good mechanical, physical and chemical stabilities and are useful in reverse osmosis and ultrafiltration processes, particularly for desalting solutions of low molecular weight organic compounds.

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