Unimatec Co., Ltd

Nippon Medtron, Limited

Jun Kanega

Takashi Enokida

Satoru Saito

Keisuke Kokin

Katsumi Suzuki

Mitsuru Maeda

Okimasa Yamada

Masashi Kudo

Ji-Shan Jin

Takashi Obara

Yasunori Yanai

Shigeru Kumamoto

Satoshi Horie

Jishan Jin

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 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 elastomer having a copolymer composition, which comprises 50-85% by mole of (a) vinylidene fluoride, 0-25% by mole of (b) tetrafluoroethylene, 7-20% by mole of (c) perfluoro(methyl vinyl ether), 3-15% by mole of (d) CF&#x2550;CFO[CFCF(CF)O]nCFand 0.1-2% by mole of (e) RfX, where Rf is an unsaturated fluorohydrocarbon group having 2-8 carbon atoms and X is a bromine or iodine atom, can give curing products with distinguished low-temperature characteristics and solvent resistance without deteriorating the distinguished moldability and compression set characteristics proper to the fluorine-containing elastomer, and a fluorine-containing elastomer composition, which comprises 100 parts by weight of the present 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 not less than 2 parts by weight of an acid acceptor can give curing products with distinguished low-temperature characteristics and fuel oil resistance.

Fluorine-containing elastomer and its composition

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.

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Jun Kanega