Asahi Kasei Kogyo Kabushiki Kaisha

Toshioki Hane

Kyoji Kimoto

Hirotsugu Miyauchi

Jukichi Ohmura

Mikio Ebisawa

Itaru Watanabe

Sakae Tsushima

Yasumichi Yamakoshi

Mitsunobu Fukumoto

Maomi Seko

Shigeki Katayama

Hisao Koike

Naomi Seko

The present invention relates to an expanded product comprising a thermoplastic fluroine type resin which does not have a cross-linking structure and has an expansion ratio of between 4-fold and 30-fold and a closed cell percentage of 40% or more. The expanded product contains at least one interface comprising layers having different cell densities and has a distribution index (Sc) and a coefficient of variation (Cv) of the maximum diameter of an open cell present at an optional cross section of each layer of 0&lt;Sc.ltoreq.6 and 0&lt;Cv.ltoreq.1, respectively, which are represented by the following equations:

Expanded fluorine type resin products and a preparation process thereof

There is disclosed a fiber of a fluorocarbon polymer having pendant ion exchange groups, the fiber having a tensile strength at break as high as at least 1.0 g/denier. The fiber can be produced by subjecting to hydrolysis or chemical modification treatment a filament of a fluorocarbon polymer having ion exchange precursor groups in melt-fabricatable form to convert the ion exchange precursor groups to ion exchange groups in melt-nonfabricatable form and subjecting the resultant heat-infusible filament to drawing.

Fiber of a fluorocarbon polymer and a process for producing the same

A cation exchange membrane of a fluorocarbon polymer containing pendant carboxylic acid and/or carboxylate groups, preferably having, at a predetermined ratio, pendant carboxylic acid and/or carboxylate groups and pendant sulfonic acid and/or sulfonate groups uniformly distributed therein, is produced by contacting with a reducing agent a fluorocarbon polymer containing pendant groups of the formula:

Cation exchange membrane of a fluorocarbon polymer and a process for

A novel fluorinated copolymer is prepared by copolymerization of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1 and l is an integer of 3 to 5, which is prepared from starting materials which are also novel. Said copolymer is useful for preparation of a fluorinated cation exchange membrane having carboxylic acid groups and/or sulfonic acid groups which can be used advantageously in electrolysis of an aqueous alkali metal halide solution with improved electrolysis performance.

Fluorosulfonylperfluoroalkyl compounds

A novel fluorinated cation exchange membrane containing carboxylic acid groups and sulfonic acid groups, both in the form of a specific pendant structure, the carboxylic acid groups being at least 20% on one surface of the membrane and gradually decreasing toward the innerside of the membrane, which membrane is useful in electrolysis of an aqueous alkali metal halide solution with advantageously stable performance for a long term under more severe operational conditions than those conventionally used. The membrane can be prepared from a novel copolymer of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1, l is an integer of 3 to 5, Z is --S-- or --SO.sub.2 -- and R is C.sub.1 -C.sub.10 alkyl, an aryl, C.sub.1 -C.sub.10 perfluoroalkyl.

Intermediates for fluorinated cation exchange membrane

A novel fluorinated cation exchange membrane containing carboxylic acid groups and sulfonic acid groups, both in the form of a specific pendant structure, the carboxylic acid groups being at least 20% on one surface of the membrane and gradually decreasing toward the innerside of the membrane, which membrane is useful in electrolysis of an aqueous alkali metal halide solution with advantageously stable performance for a long term under more severe operational conditions than those conventionally used. The membrane can be prepared from a novel copolymer of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1, l is an integer of 3 to 5, Z is --S-- or --SO.sub.2 -- and R is C.sub.1 -C.sub.10 alkyl, an aryl, Cl or C.sub.1 -C.sub.10 perfluoroalkyl. Acyl fluorides, which are the precursors of the fluorinated olefin ethers, are also disclosed.

Fluorinated ether acyl fluorides having alkylthio or alkylsulfone groups

Perfluoro vinyl ethers

A novel fluorinated copolymer is prepared by copolymerization of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1 and l is an integer of 3 to 5, which is prepared from starting materials, which are also novel. Said copolymer is useful for preparation of a fluorinated cation exchange membrane having carboxylic acid groups and/or sulfonic acid groups which can be used advantageously in electrolysis of an aqueous alkali metal halide solution with improved electrolysis performance.

Perfluorinated fluorosulfonylalkyleneoxy-2-propanoyl fluoride and

A novel fluorinated cation exchange membrane containing carboxylic acid groups and sulfonic acid groups, both in the form of a specific pendant structure, the carboxylic acid groups being at least 20% on one surface of the membrane and gradually decreasing toward the innerside of the membrane, which membrane is useful in electrolysis of an aqueous alkali metal halide solution with advantageously stable performance for a long term under more severe operational conditions than those conventionally used. The membrane can be prepared from a novel copolymer of a fluorinated olefin with a novel sulfur containing fluorinated vinylether of the formula: ##STR1## wherein k is 0 or 1, l is an integer of 3 to 5, Z is --S-- or --SO.sub.2 -- and R is C.sub.1 -C.sub.10 alkyl, an aryl, Cl or C.sub.1 -C.sub.10 perfluoroalkyl.

Fluorinated vinyl ether compounds and process for producing the same

A fluorinated cation exchange membrane characterized by the gradual decrease in proportion of the density of carboxylic acid and/or carboxylate groups relative to the total density of carboxylic acid and/or carboxylate groups and sulfonic acid and/or sulfonate groups from one surface of the membrane to the other surface or an internal plane therewithin. The cation exchange membrane of the present invention can be prepared by treating one surface of a membrane comprising a fluorocarbon polymer containing pendant groups of the formula:

Fluorinated cation exchange membrane and process for preparing the same

Fluorinated cation exchange membrane

Novel fluorinated cation exchange membrane and process for producing the

A novel fluorinated copolymer is prepared by copolymerization of a fluorinated olefin with a novel sulfur containing fluorinated vinyl ether of the formula: ##STR1## wherein k is 0 or 1 and l is an integer of 3 to 5, which is prepared from starting materials which are also novel. Said copolymer is useful for preparation of a fluorinated cation exchange membrane having carboxylic acid groups and/or sulfonic acid groups which can be used advantageously in electrolysis of an aqueous alkali metal halide solution with improved electrolysis performance.

Novel fluorinated copolymer with tridihydro fluorosulfonyl fluoride

An electrolytic cell having anode and cathode chambers separated by a cation exchange membrane comprising a fluorocarbon polymer containing pendant carboxylic acid or salt groups of the formula ##STR1## wherein R is a group containing perfluoroalkyl or perfluoroalkoxy having 1 to 5 carbon atoms and M is hydrogen, an alkali or alkaline earth metal or ammonium as a surface stratum on the cathode side of the membrane. The fluorocarbon polymer may also contain sulfonic acid groups of the formula ##STR2##

Electrolysis of aqueous alkali metal halide solution

Cation exchange membrane comprising a fluorocarbon polymer characterized by the presence of pendant carboxylic acid groups of the formula -- OCF.sub.2 COOH -- and derivatives thereof.

Growing community of inventors

Kanagawa, Japan

Toshioki Hane