Patent · US Expired

Asymmetrical membrane of polyester-amide and process for preparing it

US4879036A · kind A · utility

2Cited by
3References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 9, 1987
Grant dateNov 7, 1989
Priority date
Expiry dateJun 9, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D71/56
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An asymmetrical membrane for use in dialysis and ultra-filtration is prepared using a polyester-amide (TATE).sub.n, wherein T represents a radical of terephthalic acid, A represents a radical of hexamethylenediamine, and E represents a radical of hexanediol, in a solvent of formic acid or in a solvent comprising a solution of lithium chloride in dimethylformamide or dimethylacetamide. The polyester-amide (TATE).sub.n is formed into a thin layer and placed into an aqueous coagulation bath to coagulate the resulting membrane. The membrane has a thickness of from 15 to 190 .mu.m, a water permeability of from about 3 up to about 9 liters/m.sup.2 /hour for a .DELTA.P of 300 mm.sub.HG and is permeable for substances having a molecular weight of up to about 17,000.

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