Asahi Glass Company, Limited

Nec Corporation

Sasakura Engineering Co., Ltd.

Hiroshi Funaki

Masayuki Saito

Hiroki Kamiya

Yasuhiko Matsuoka

Ryuji Seki

Makoto Honda

Takehiro Kose

Mitsuru Seki

Junpei Nomura

Kunio Watanabe

Kazuya Oharu

Shinya Higuchi

Jun Hoshikawa

Keigo Matsuura

Shoji Furuta

Koichi Yanase

Yasushi Nishimura

Kunihiko Terase

Jumpei Nomura

Takao Hirono

Tomoko Sato

Hachirou Hirano

Hiroo Mori

Shiro Ohno

Toshikazu Yoneda

Yoshimasa Kai

Masao Uehara

Kenichiro Nagatomo

Ng Soon Yeng

Satoru Hirano

To provide a fluorinated elastomer composition which can improve, in production of a fluorinated foamed rubber by foaming and crosslinking a fluorinated elastomer using an organic peroxide as a crosslinking agent, the foamed state and physical properties of the fluorinated foamed rubber. A fluorinated elastomer composition which comprises 100 parts by mass of a fluorinated elastomer, from 0.1 to 20 parts by mass of a blowing agent and from 0.05 to 10 parts by mass of a crosslinking agent comprising a peroxide compound, and which contains no crosslinking aid or contains a crosslinking aid comprising a compound having at least two carbon-carbon double bond-containing groups in the same molecule, in a content of at most 0.3 part by mass, is foamed and crosslinked to produce a fluorinated foamed rubber.

Fluorinated elastomer composition and fluorinated foamed rubber

A fluorinated elastic copolymer which has iodine atoms, bromine atoms, or both iodine and bromine atoms, at its molecular terminals and which includes repeating units (a) based on tetrafluoroethylene, repeating units (b) based on a fluorinated monomer having one polymerizable unsaturated bond (provided that tetrafluoroethylene is excluded), and repeating units (c) based on a fluorinated monomer having at least two polymerizable unsaturated bonds, wherein the ratio (molar ratio) of the repeating units (a) to the repeating units (b) is (a)/(b)=40/60 to 90/10, and the proportion of the repeating units (c) based on the total amount of the repeating units (a) and the repeating units (b) is from 0.01 to 1 mol %.

Fluorinated elastic copolymer and process for its production, and crosslinked rubber article

To provide a fluorinated elastic copolymer having high crosslinkability, having high flowability and excellent in the compression set and the resistance to bases, and its production process. A process for producing a fluorinated elastic copolymer, which comprises copolymerizing (a) tetrafluoroethylene and (b) propylene and as the case requires, (c) a perfluoro(alkyl vinyl ether) in the presence of an iodine compound represented by the formula RI(wherein R is a hydrocarbon group or perfluoroalkyl group having at least 3 carbon atoms) at a temperature of from 0&#xb0; C. to 50&#xb0; C., and a fluorinated elastic copolymer obtained by the production process.

Fluorinated elastic copolymer and production process

The present invention provides a fluorinated polymer excellent in the crosslinking reactivity, crosslinked rubber physical properties and chemical resistance, and its crosslinked rubber. A fluorinated polymer comprising repeating units (a) based on at least one monomer selected from the group consisting of ethylenic unsaturated compounds each having a hydroxyphenyl group, repeating units (b) based on at least one fluoromonomer selected from the group consisting of tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride, 3,3,3-trifluoropropene, 1,3,3,3-tetrafluoropropene, 1,1,2-trifluoroethylene, vinyl fluoride, 1,2-difluoroethylene and CF&#x2550;CF&#x2014;O&#x2014;R(wherein Ris a Csaturated perfluoroalkyl group or a perfluoro(alkoxyalkyl) group) and, if necessary, repeating units (c) based on at least one hydrocarbon monomer selected from the group consisting of ethylene, propylene and CH&#x2550;CH&#x2014;O&#x2014;R.

Fluorinated polymer

An elastic fluorocopolymer comprises repeating units (l) based on a fluoromonomer such as tetrafluoroethylene, hexafluoropropylene, vinylidene fluoride or CF&#x2550;CF&#x2014;O&#x2014;R(wherein Ris a Csaturated perfluoroalkyl group or a perfluoro(alkoxyalkyl) group) and repeating units (m) based on the formula CRR&#x2550;CRCOOCH&#x2550;CH(wherein each of Rand Ris a hydrogen atom, a Calkyl group or a Calkoxyalkyl group containing an etheric oxygen atom, and Ris a hydrogen atom, a fluorine atom or a methyl group) in a molar ratio of (m)/((l)+(n))=0.0001 to 0.1. Further, an elastic fluorocopolymer composition comprises (A) the above elastic fluorocopolymer, (B) an unsaturated multifunctional compound and (C) a bivalent metal oxide and/or hydroxide. The elastic fluorocopolymer and the elastic fluorocopolymer composition are excellent in the crosslinkability and can provide a crosslinked rubber thereof excellent in crosslinked rubber properties.

Elastic fluorocopolymer, its composition and crosslinked rubber

The current invention relates to a fluorinated elastomer latex containing an aqueous medium, a fluorinated elastomer dispersed in the aqueous medium in an amount of from 10 to 60 mass % and a fluorinated emulsifier represented by the formula (1): CFO(CFCFO)CFCOOA (wherein A is a hydrogen atom, an alkali metal or NH, and m is an integer of from 1 to 3), which employs no perfluorooctanoate emulsifier and which is excellent in dispersion stability of the fluorinated elastomer.

Fluorinated elastomer latex, its production method, fluorinated elastomer and fluororubber molded product

A simple and efficient method for regenerating a basic anion-exchange resin, whereby at the time of removing a fluorinated emulsifier from a basic anion-exchange resin having the fluorinated emulsifier adsorbed thereon, it is unnecessary to provide a safety device/recovery technique necessary for handling an organic solvent by the use of a combustible organic solvent represented by an alcohol, and a burden imposed by e.g. treatment against COD load, is eliminated. A basic anion-exchange resin having a fluorinated emulsifier adsorbed thereon is contacted with an aqueous alkaline solution having a temperature of from 60 to 105&#xb0; C. to elute the fluorinated emulsifier thereby to regenerate the basic anion-exchange resin.

Method for regenerating basic anion-exchange resin

A process for producing an elastic fluorocopolymer, by emulsion-polymerizing at least one fluoromonomer (a), a vinyl ester monomer (b) represented by the formula CRR&#x2550;CRCOOCH&#x2550;CHoptionally, at least one hydrocarbon monomer (c) selected from the group consisting of ethylene, propylene and a vinyl ether, in an aqueous medium to produce an elastic fluorocopolymer latex, adjusting the pH of the elastic fluorocopolymer latex to from 1 to 9, and coagulating the elastic fluorocopolymer latex to isolate an elastic fluorocopolymer.

Process for producing elastic fluorocopolymer and crosslinked fluororubber

A perfluoroelastomer composition comprises a perfluoroelastomer (e.g., tetrafluoroethylene/perfluoro(methyl vinyl ether) copolymer), an organic peroxide (e.g., 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and a scorch retarder (e.g., o-phenylphenol), and the perfluoroelastomer composition is excellent in processability and unlikely to scorch. Furthermore, a perfluoro rubber molded article obtained by thermal crosslinking of the perfluoroelastomer composition is excellent in rubber physical properties such as tensile strength and elongation at break and in a compression set property.

Perfluoroelastomer composition and perfluoro rubber molded article

A fluorecopolymer which comprises repeating units (a) based on tetrafluoroethylene, repeating units (b) based on perfluoro(methyl vinyl ether) and repeating units (c) based on perfluoro(propyl vinyl ether) in a molar ratio of (a)/(b)/(c) of 40-70/3-57/3-57. The fluorocopolymer is a perfluoroelastomer which is excellent in low temperature characteristics, heat resistance and chemical resistance.

Fluorocopolymer

An aqueous solution containing a fluorine-containing emulsifier in a low concentration of at least 1 ppm by mass and at most 1% by mass (e.g., coagulation waste water after an emulsion polymerization of a fluoropolymer and/or an aqueous solution obtained by washing with an aqueous solution a waste gas from a drying process and/or a heat treating process of the fluoropolymer) is subjected to vacuum concentration under a pressure of at most 100 kPa and a temperature of the aqueous solution of at most 100&#xb0; C. by means of a heating tube surface evaporation type concentrator equipped with a heat pump or the like, and the fluorine-containing emulsifier is recovered from a highly concentrated aqueous solution containing the fluorine-containing emulsifier in a higher concentration of at least 5% by mass. According to the present method, the fluorine-containing emulsifier can be recovered with a high yield from a low-concentration liquid such as coagulation waste water of a fluoropolymer.

Method for recovering fluorine-containing emulsifier

Water repellent and oil resistant composition

A water dispersion type water and oil repellent composition containing a copolymer (A) which is a copolymer containing polymerized units based on a polymerizable monomer having a polyfluoroalkyl group and polymerized units based on stearyl (meth)acrylate, and which is produced by using a material having a purity of stearyl (meth)acrylate higher than 91 mass %, wherein the ratio of particles having an average particle diameter of from 30 to 150 nm is at least 80% of the total number of particles of the copolymer (A) in a dispersion medium.

Water dispersion type water and oil repellent composition and object treated with the same

A water dispersion type water and oil repellent composition which undergoes little change in viscosity even if freezing/thawing cycles are repeated and which is excellent in storage stability. The dispersion is capable of imparting excellent water and oil resistance to paper. A water dispersion type water and oil repellant composition contains a compound which is mixable with water and has a flash point of from 50 to 150&deg; C. A polyfluoroalkyl group-containing phosphate may be incorporated into the mixture.

Water-and-oil repellant composition of aqueous dispersion type

A process for producing zinc oxide-containing spherical silica, which comprises emulsifying, in an organic solvent containing a surfactant, a dispersion having zinc oxide with a particle size of from 0.005 to 0.5 .mu.m dispersed in an aqueous alkali metal silicate solution in an amount of from 10 to 70 wt % based on the total amount of zinc oxide and SiO.sub.2 in the aqueous alkali metal silicate solution, followed by gelation of the resulting emulsion with carbon dioxide gas.

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Ichihara, Japan

Hiroshi Funaki