Nippon Mektron Limited

Unimatec Co., Ltd

Nippon Medtron, Limited

Takashi Enokida

Jun Kanega

Haruyoshi Tatsu

Okimasa Yamada

Keisuke Kokin

Akihiro Naraki

Katsumi Suzuki

Eiichi Yamashita

Yasunori Yanai

Satoru Saito

Seiichiro Murata

Mitsuru Maeda

Daisuke Murai

Ji-Shan Jin

Satoshi Kurihara

Takashi Obara

Shinichi Sonobe

Hajime Akimoto

Hideo Aoki

Jishan Jin

Daisuke Fujihara

Shigeru Kumamoto

A fluorine-containing alloyed copolymer, which comprises a fluorine-containing elastomer copolymer having a fluorine content of not less than 64% by weight, and a resinous tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer having an amount of heat of crystal fusion &#x394;H of not more than 10 J/g, can give crosslinked moldings having a distinguished plasma resistance against both CFplasma treatment and Oplasma treatment, and also a distinguished cracking resistance at the plasma irradiation, and showing necessary normal state physical properties and compression set when used as seals, and capable of providing soft seals of low hardness, and attaining molding at relatively low temperatures.

Fluorine-containing alloyed copolymer

A polyfluoroalkane carboxylic acid represented by the following general formula:CF(CHCF)(CFCF)CFCOOM(M: an alkali metal, a NHgroup or H; n: an integer of 1 to 6; m: an integer of 1 to 4; and l: 1 or 2) can be produced by hydrolysis reaction of polyfluoroalkane carboxylic acid fluoride represented by the following general formula:CF(CHCF)(CFCF)CFCOF,where its carboxylic acid salt can be formed as an alkali metal salt, or a NHsalt. The polyfluoroalkane carboxylic acid (or its salt) can act as a surfactant having distinguished monomer emulsifiability and latex stability when used as an emulsifying agent or as a dispersing agent for polymerization reaction of fluorine-containing monomers, or as an effective surfactant capable of enhancing the micelles solubility of fluorine-containing monomers such as vinylidene fluoride, etc., when used as an emulsifying agent or a dispersing agent for homopolymerization or copolymerization reaction of vinylidene fluoride.

Polyfluoralkane carboxylic acid (or its salt) and process for producing the same

A fluorine-containing elastomer having a copolymer composition, which comprises (a) 50-85 mol. % of vinylidene fluoride, (b) 0-25 mol. % of tetrafluoroethylene, (c) 7-20 mol. % of perfluoro(methyl vinyl ether), (d) 2.5-15 mol. % of CF&#x2550;CFO[CFCF(CF)O]nCF(n: 2-6), (e) 0.1-2 mol. % of CF&#x2550;CFO[CFCF(CF)O]mCFCF(m: 2-6), and (f) 0.1-2 mol. % of RfX (Rf: an unsaturated fluorohydrocarbon group having 2-8 carbon atoms, which can contain at least one ether bond, X: bromine or iodine), can provide a fluorine-containing elastomer composition, which comprises 100 parts by weight of the fluorine-containing elastomer, 0.1-10 parts by weight of an organic peroxide, 0.1-10 parts by weight of a polyfunctional unsaturated compound, and at least 2 parts by weight of an acid acceptor. The composition can give vulcanizates having a distinguished elongation at break at high temperatures such as 100&#xb0; C., and distinguished compression set characteristics at low temperatures such as 0&#xb0; C.

Fluorine-containing elastomer and composition thereof

A fluorine-containing copolymer, which comprises a hydroxyl-terminated fluorine-containing vinyl ether, represented by the following general formula:CF&#x2550;CFORCHOH(where Rf is a fluoroalkylene group, a fluoroalkyl ether group, or a fluoroalkoxyfluoroalkyl ether group, having 1-25 carbon atoms), and at least one of other fluorine-containing unsaturated monomers, where a high-molecular weight fluorine-containing copolymer having a melt viscosity (230&#xb0; C.) of 0.1-100 g/10 min. is insoluble in a solvent, and can be used suitably for melt molding, whereas a low-molecular weight fluorine-containing copolymer having a glass transition temperature Tg of 20&#xb0; C., or higher, and a number average molecular weight Mn of 1,000, or more is soluble in a solvent, and can be used suitably for coating agents, etc. The fluorine-containing copolymer has a high light transmissivity, and a low refractive index, and also has, as such, a good adhesiveness to various substrated without any surface treatment, any adhesives, or the like.

Fluorine-containing copolymer

A process for preparing a fluorine-containing copolymer by an emulsion polymerization method in the presence of aqueous ammonia as a pH modifier, and a molded article obtainable by melt molding or crosslinking molding the fluorine-containing copolymer. In preparing the fluorine-containing copolymer by coagulation of the fluorine-containing copolymer contained in a fluorine-containing copolymer dispersed aqueous solution, it is preferred to use a cationic surfactant and a water soluble organic solvent as a coagulating agent used for the above coagulation. The surfactant is preferably represented by the, formula (RN)Xwherein R is an alkyl group of 1 to 22 carbon atoms, a fluoroalkyl group obtainable by fluorine substituting at least a part of hydrogen atoms present in the above alkyl group or hydrogen, four R's may be the same or different provided that they are not hydrogen atoms simultaneously, and X is a halogen atom. The process for preparing a fluorine-containing copolymer provides a decrease in a concentration of metal elements, which act as an impurity source, for example, having a metal element concentration of not more than 1 ppm.

Process for producing fluorocopolymer

A fluorine-containing terpolymer with distinguished transparency and strength at ordinary temperature and at elevated temperatures when heated, which comprises 20&#x2013;98% by weight of tetrafluoroethylene, 1&#x2013;40% by weight of perfluoro(ethyl vinyl ether) and 1&#x2013;40% by weight of perfluoro(propyl vinyl ether) and has a specific melt viscosity of 0.1&#xd7;10&#x2013;110&#xd7;10Pa&#xb7;s (372&#xb0; C.). The fluorine-containing terpolymer preferably has a comonomer ratio of perfluoro(propyl vinyl ether) to perfluoro(ethyl vinyl ether) of 1.0 or more by weight.

Fluorinated terpolymer

Process for producing fluorinated copolymer, fluorinated copolymer, crosslinkable composition containing same and sealant

A fluorine-containing copolymer composition comprising a fluorine-containing elastomer and a fluororesin, both having reaction sites capable of reacting with a common crosslinking agent gives crosslinking molding products having distinguished roll processability, moldability and mechanical strength, where crosslinking molding is carried out preferably by a peroxide crosslinking system or polyol crosslinking system, and the low temperature characteristics is considerably improved when the fluororesin has a softening point of not less than 120.degree. C.

Flourine-containing copolymer composition

A fluorine-containing graft copolymer produced by copolymerizing at least two kinds of monomers selected from the group consisting of fluorinated monomers and propylene in the presence of a saturated iodine-containing compound or an iodine and bromine-containing compound, and further graft copolymerizing the resulting copolymer with tetrafluoroethylene and polyfluorovinyl ether represented by the general formula:

Process for producing fluorine-containing graft copolymer

A fluoroelastomer comprising 74 to 80% by mole of vinylidene fluoride, 4 to 12% by mole of tetrafluoroethylene, 14 to 18% by mole of hexafluoropropene and 0.3 to 1.3% by mole of perfluoro(alkyl vinyl ether), the sum total being 100% by mole, gives vulcanization products having well balanced high levels of low-temperature characteristics and methanol resistance, and suppressed change in the hardness with time after the secondary vulcanization.

Fluoroelastomer and its cross-linkable composition

A fluoroelastomer comprising 2 to 8% by mole of tetrafluoroethylene, 14 to 25% by mole of perfluoro(alkyl vinyl ether) and 70 to 85% by mole of vinylidene fluoride, sum total being 100% by mole, obtained by copolymerization in the presence of a bromine-containing monomer compound and an iodine and bromine-containing compound, has distinguished low temperature characteristics, solvent resistance and chemical resistance by itself.

A fluorine rubber composition comprising a fluorine rubber and a polyfluoroalkyl group-containing block isocyanate compound represented by the following general formula:

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Takashi Enokida