摘要:
Polytetrafluoroethylene molding powder which comprises 0.01 to 1% by weight of a perfluoro(vinyl ether) unit and which has a heat of crystallization of 18.0 to 25.0 J/g. The molding powder provides a molded article which has a flex life of not less than 7 million cycles, a creep resistance (total deformation at 200.degree. C.) of not more than 20%, and a creep resistance (total deformation at 25.degree. C.) of not more than 15%. The polytetrafluoroethylene molding powder which is excellent in both creep resistance and flex fatigue resistance is provided as a molding material for parts which are repeatedly bent such as pump.
摘要:
Polytetrafluoroethylene molding powder which comprises 0.01 to 1% by weight of a perfluoro(vinyl ether) unit and which has a heat of crystallization of 18.0 to 25.0 J/g. The molding powder provides a molded article which has a flex life of not less than 7 million cycles, a creep resistance (total deformation at 200.degree. C.) of not more than 20%, and a creep resistance (total deformation at 25.degree. C.) of not more than 15%. The polytetrafluoroethylene molding powder which is excellent in both creep resistance and flex fatigue resistance is provided as a molding material for parts which are repeatedly bent such as pump.
摘要:
A fluorovinyl ether of the formula:R.sub.f --(OCF.sub.2 CF.sub.2 CF.sub.2).sub.n --OCF.dbd.CF.sub.2(I)wherein R.sub.f is a C.sub.1- -C.sub.5 perfluoroalkyl group, n is an integer of 1 to 4 provided that when n is 1 (one), R.sub.f is other than a trifluoromethyl group, a copolymer of which with an ethylenically unsaturated compound has a low glass transition temperature and improved low temperature properties.
摘要:
A fluorovinyl ether of the formula:R.sub.f --(OCF.sub.2 CF.sub.2 CF.sub.2).sub.n --OCF.dbd.CF.sub.2(I)wherein R.sub.f is a C.sub.1 -C.sub.5 perfluoroalkyl group, n is an integer of 1 to 4 provided that when n is 1 (one), R.sub.f is other than a trifluoromethyl group, a copolymer of which with an ethylenically unsaturated compound has a low glass transition temperature and improved low temperature properties.
摘要:
A fluorovinyl ether of the formula:XCH.sub.2 CF.sub.2 CF.sub.2 --(OCH.sub.2 CF.sub.2 CF.sub.2).sub.m --(OCFYCF.sub.2).sub.n --OCF.dbd.CF.sub.2 (I)wherein X is a hydrogen atom or a halogen atom (e.g. fluorine, chlorine, bromine and iodine); Y is a fluorine atom or a trifluoromethyl group; m is an integer of 0 to 5; and n is 0, 1 or 2, which can modify a polymer of at least one ethylenically unsaturated compound.
摘要:
The invention provides a fluoropolymer composition capable of improving the characteristics of the cured material obtained therefrom. A fluoropolymer composition comprising a methylene group-containing fluoropolymer (A) and a hydrosilylation catalyst (B), wherein the methylene group-containing fluoropolymer (A) has methylene group-containing repeating units in the main chain thereof and is capable of hydrosilylation in the presence of the hydrosilylation catalyst (B) and one terminus of the chain is a carbon-carbon double bond or an Si—H group and the other terminus of the chain is an Si—H group or a carbon-carbon double bond.
摘要:
A fluoroelastomer mixture, including: a peroxide-vulcanizable fluoroelastomer (A) containing an iodine atom; and a peroxide-vulcanizable fluoroelastomer (B) containing an iodine atom. The fluoroelastomer (A) is a copolymer (a1) consisting of 50 to 85 mol % of a vinylidene fluoride unit and 15 to 50 mol % of a perfluoro(alkyl vinyl ether) unit, or a copolymer (a2) consisting of 45 to 85 mol % of a vinylidene fluoride unit, 1 to 30 mol % of a tetrafluoroethylene unit, and 14 to 30 mol % of a perfluoro(alkyl vinyl ether) unit. Further the fluoroelastomer (B) has a fluorine content of 70.0% or more. Also disclosed is a composition for peroxide vulcanization containing the above fluoroelastomer composition (i), a polyfunctional unsaturated compound (ii) and a peroxide (iii), as well as a method for producing the fluoroelastomer mixture.
摘要:
A curable composition comprising (A) a vinylidene fluoride type elastomer which is a copolymer of vinylidene fluoride (a1), at least one perfluoroolefin (a2) selected from the group consisting of tetrafluoroethylene, hexafluoropropylene and perfluoro(alkyl vinyl ether) and a cyano group-containing monomer (a3) (the proportion of vinylidene fluoride exceeds 20% by mole), and (B) a compound generating ammonia at 40° to 330° C. alone as a curing agent. The present invention can provide a curable composition of a vinylidene fluoride type elastomer assuring improved crosslinking speed and making it possible to use a cheap curing agent, and a molded article obtained from the curable composition. Physical properties under normal conditions can also be improved by the presence of the solvent having affinity for the compound generating ammonia.
摘要:
To provide a novel crosslinking system of fluorine-containing elastomer giving a crosslinked product particularly having improved mechanical strength and compression set at high temperature. A fluorine-containing rubber composition comprising a fluorine-containing elastomer having carboxyl group and/or alkoxycarbonyl group at an end of a trunk chain and/or branched chain as a crosslinkable group.
摘要:
The present invention has for its object to provide a fluorocopolymer which is available at low cost, has fluidity at room temperature, and is curable, a method of producing the same copolymer and a curable composition having good processability and in situ moldability.The present invention is directed to a fluorocopolymer which is fluid at room temperature and curable, and which is obtainable from a trifluorovinyl group-containing monomer with an ethylenically unsaturated double bond moiety being a trifluorovinyl group.