Patent · US Expired

Process for producing aromatic polyimide composite separating membrane

US4440643A · kind A · utility

53Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 11, 1982
Grant dateApr 3, 1984
Priority date
Expiry dateJun 11, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31721
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An aromatic polyimide composite membrane having an excellent gas-separating property is produced by a process comprising the steps of: coating at least one surface of a substrate consisting of an aromatic polyimide porous membrane with a solution of 0.05% to 10% by weight of an aromatic polyamic acid in a polar organic solvent, which is not capable of dissolving the polyimide porous membrane, at a temperature not exceeding 140.degree. C.; after a during drying the resultant thin coating layer of the polyamic acid solution, heating the resultant polyamic acid layer at a temperature of 150.degree. C. or more so as to convert the polyamic acid layer to the corresponding polyimide layer.

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