E.i. Dupont De Nemours and Company

Donaldson Comapny, Inc.

James T Keating

Stephen A Perusich

Peter Popper

Thomas C Bissot

James M Batman

Everett Ira Baucom

Jeffrey E Spethmann

A composite membrane including an ion exchange polymer and a support of expanded polytetrafluoroethylene polymer having a porous microstructure of polymeric fibrils, said expanded polytetrafluoroethylene polymer being at least about 85% crystalline.

Composite membrane with highly crystalline porous support

The operation of electrolytic cells employing ion exchange membranes is improved by addition to the catholyte of a fluorinated ionomer resin resulting in a long-term reduction in the operating voltage of the electrolytic cell.

Electrolysis method using polymer additive for membrane cell operation

An ion exchange membrane reinforced with leno weave yarn system having sacrificial fibers paired with resistant fibers in the warp of the fabric, and an electrolysis process using the membrane are disclosed.

Membrane reinforced with modified leno weave fabric

An ion exchange membrane reinforced with a multiaxial, preferably triaxial, yarn system and an electrolysis process using the membrane in its highly-fluorinated cation exchange form.

Multiaxially reinforced membrane

A coated cation exchanged fabric having as its base a fluorinated cation exchange resin, oriented at least 1x, in alkali metal salt form and as its coating an unoriented or oriented melt-fabricable precursor of the same salt-form fluorinated cation exchange resin. The invention also includes various processes for making the coated fabric.

Coated cation exchange fabric and process

A fluorinated cation exchange membrane made using reinforcement of oriented, hydrolyzed fabric of a cation exchange copolymer, the fabric having a coating of a melt-processible precursor or derivative of a fluorinated cation exchange resin on at least one surface or throughout.

Cation exchange membrane and use

A sheath/core yarn having as its core a fluorinated cation exchange resin, oriented at least 1x, in alkali metal salt form and as its sheath an unoriented or oriented melt-fabricable precursor or derivative of the same salt-form fluorinated cation exchange resin. The invention also includes various processes for making the sheath/core yarn.

Coated cation exchange yarn and process

A fluorinated cation exchange membrane comprising one or more layers of an ion-conductive film and where one or more layers has adhered therein a fabric reinforcement made from fully ion conductive yarn that is oriented and then at least partially hydrolyzed, the film and the yarns being made of melt-fabricable fluorinated cation exchange resin precursors having a mole ratio of non-functional to functional monomer of 2.8-11.8:1, the mole ratio in the film adjacent to the fabric being different from that of the fabric by no more than three units, where the membrane is employed in the process of electrolyzing alkali metal halides.

Cation exchange reinforced membrane and process for using

A presoaked perhalogenated polymer cation exchange membrane containing at least one type of acid groups, carboxyl or sulfonyl, is bonded to other articles such as edge-reinforcing tape, gasket, electrolytic cell frame, etc., by means of a pressure-sensitive adhesive material from the group of butyl rubber, styrene-butadiene rubber, and polyacrylate rubber. Presoaking of the membranes is done either in water or in an aqueous alkaline solution.

Growing community of inventors

Wilmington, DE, United States of America

James T Keating