Patent · US Expired

Reinforced ion exchange membrane and a process for producing the same

US4913817A · kind A · utility

9Cited by
0References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1988
Grant dateApr 3, 1990
Priority date
Expiry dateJun 17, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08J2381/08
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An ion exchange membrane reinforced by a woven reinforcing fabric is provided in which the difference between the thickness of the membrane at the crossover points where the warp and weft strands of the fabric cross each other and that at the window portions defined by the crossed warp and weft strands is not greater than 35 .mu.m. This membrane may be produced for example, by heating an assembly comprising at least two fluorinated polymer films each having pendant sulfonyl groups and/or carboxyl groups in a melt-fabricable form, and a woven reinforcing fabric sandwiched between the polymer films, and a support sheet laminated to the outermost polymer film, while applying a negative pressure to one side of the assembly that is remote from the support film, followed by converting the sulfonyl and/or carboxyl groups of the polymer films to sulfonate and/or carboxylate groups. This reinforced ion exchange membrane has flat film surfaces, thereby eliminating the danger of gas bubbles during chloralkali electrolysis which enables the cell voltage to be low, so that electric power consumption can be reduced.

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