Patent · US Expired

Low and medium flux membranes

US5693694A · kind A · utility

2Cited by
24References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 20, 1996
Grant dateDec 2, 1997
Priority date
Expiry dateMar 20, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G2340/00
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A casting solution for preparing a low to medium flux membrane. The casting solution contains 19-25% by weight polysulfone, polyethersulfone, or polyarylsulfone; 14-32% by weight a hydrophilic compatible polymer; 0.1-6% by weight an isocyanate capped polyethylene glycol urethane polymer; and 37-67% by weight an aprotic and water miscible solvent; in which the polysulfone, polyethersulfone, or polyarylsulfone has a M.W. of 10,000-100,000 daltons, the isocyanate capped polymer contains 2-5 --N.dbd.C.dbd.O groups per molecule and has a M.W. of 500-5,000 daltons, and the compatible polymer contains 2-5 --CH.sub.2 OH groups per molecule and has a M.W. of 200-1,000 daltons. Also disclosed are a method of spinning this casting solution to form a hollow fiber and the hollow fiber thus obtained.

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