摘要:
An easily cross linkable fluorine-containing polymer comprising: (1) a polymeric chain comprising one or more polymer segments, at least one polymer segment of which consists of units of at least one fluorine-containing ethylenically unsaturated compound having 2 to 8 carbon atoms, or units of said fluorine-containing ethylenically unsaturated compound and at least one other monomer selected from the group consisting a fluorine-free ethylenically unsaturated compound having 2 to 4 carbon atoms and a fluorine-containing diene having 4 to 8 carbon atoms, (2) at least one bromine atom liberated from a brominated compound of the formula: RBr.sub.x (wherein R is a saturated hydrocarbon residue and x is a number corresponding to the bonding valency of the residue R) in an amount of 0.001 to 10% by weight based on the polymer weight and (3) a fragment of the brominated compound excluding the said liberated bromine atom therefrom, bonded to the polymeric chain, the polymer being prepared by polymerizing said fluorine-containing ethylenically unsaturated compound with or without said other monomer in the presence of a radical producing source and the brominated compound in at least one step.
摘要:
A co-crosslinkable blend composition which comprises (1) an iodine-containing fluoroelastomer, (2) at least one of silicone oligomers, silicone elastomers, fluorosilicone elastomers, phosphonitrilic fluoroelastomers, tetrafluoroethylene/propylene copolymers and hexafluoropropylene/ethylene copolymers and (3) an organic peroxide.
摘要:
An easily cross linkable fluorine-containing polymer substantially comprising: (1) a polymeric chain comprising one or more polymer segments, of which at least one polymer segment consisting of units of vinylidene fluoride alone or of units of vinylidene fluoride and one or more of other fluoroolefins, and (2) at least one iodine atom liberated from an iodinated compound of the formula: RI.sub.x (wherein R is a saturated or unsaturated fluorohydrocarbon or chlorofluorohydrocarbon residue having 1 to 8 carbon atoms and x is an integer of 1 or 2 corresponding to the bonding valency of the residue R) in an amount of 0.001 to 10% by weight based on the polymer and (3) a fragment of the iodinated compound excluding the said liberated iodine atom therefrom, which are bonded to the polymeric chain and being prepared by polymerizing vinylidene fluoride with or without one or more of the other fluoroolefins in the presence of a radical producing source and the iodinated compound or its reaction product with the said monomer(s) in one or more steps, the other fluoroolefins being selected from the group consisting of tetrafluoroethylene, chlorotrifluoroethylene, trifluoroethylene, vinyl fluoride, hexafluoropropylene, pentafluoropropylene, perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether) and perfluoro(propyl vinyl ether).
摘要:
A fluorine-containing polymer substantially comprising (A) at least one fluorine-containing olefin of the formula:CF.sub.2 =CXYwherein X is a hydrogen atom or a fluorine atom and Y is a hydrogen atom, a chlorine atom, a fluorine atom, a trifluoromethyl group, a difluoromethyl group, a C.sub.1 -C.sub.3 perfluoroalkoxy group or a group of the formula:--(CF.sub.2).sub.m COOMwherein m is an integer of 0 to 3 and M is a hydrogen atom, a C.sub.1 -C.sub.4 alkyl group, a sodium atom or a potassium atom but when X is a hydrogen atom, Y is always a hydrogen atom, (B) one or more C.sub.4 -C.sub.8 fluorine-containing dienes, (C) at least one iodine atom and (D) at least one saturated or unsaturated fluoro or chlorofluorohydrocarbon group, the molar ratio of the diene (B) and the olefin (A) being from 1.times.10.sup.-4 to 5.times.10.sup.-2, the iodine atom(s) (C) being from 0.001 to 10% by weight based on the weight of the polymer and the molar ratio of the group (D) and the olefin (A) being from 1.times.10.sup.-5 to 5.times.10.sup.-2, can be cross-linked at atmospheric pressure at a cross-linking temperature in the presence of a cross-linking agent. The fluorine-containing polymer may be prepared by polymerizing (B) with the polymerization reaction product of (A) and an iodide compound.
摘要:
An elastomeric composition comprising a fluoroelastomer, an epichlorohydrin elastomer, an acid-acceptor, a curing accelerator and a fluorine-containing polyhydroxy compound, which is handled without any difficulty and can afford, on crosslinking, a rubbery material excellent in physical and chemical properties at a wide range of temperatures.
摘要:
A composite material including a rubber elastomer substrate and a polytetrafluoroethylene resin film or sheet having a porosity of 20 to 95% by volume and being laminated on at least one portion of the rubber elastomer substrate. In one preferred embodiment, a process for the production of the composite material includes the step of laminating a vulcanizable rubber elastomer with a porous film or sheet of polytetrafluoroethyle resin at a temperature and pressure sufficient to effect vulcanization of the rubber elastomer.
摘要:
A fluororubber composition comprising a fluororubber, a vulcanizing agent and 0.1 to 5 wt. parts of a fatty acid monoamide per 100 wt. parts of said fluororubber. This fluororubber composition is excellent in mold releasability, and a molded article obtained by vulcanizing and molding the composition suffers less deterioration of mechanical properties caused by the addition of an internal mold release agent.
摘要:
A vulcanizable fluorinated rubber composition comprising a fluorinated rubber containing --CH.sub.2 --CF.sub.2 -- units in the polymeric chain, a vulcanizing agent and a vulcanization accelerator as the essential components, characterized in that the vulcanizing agent is a fluorine-containing polyhydroxy aliphatic compound.
摘要:
An impregnated material comprising an organic or inorganic material selected from the group consisting of a woven fabric, a non-woven fabric and an open cell porous material which is impregnated with a copolymer which comprises 50 to 95% by mole of repeating units derived from tetrafluoroethylene and 5 to 50% by mole of repeating units derived from perfluoroalkyl vinyl ether of the formula:CF.sub.2 .dbd.CFOR.sub.f (I)wherein R.sub.f is a C.sub.1 -C.sub.6 perfluoroalkyl group or a group of the formula:--(CF.sub.2 CFXO).sub.n --R.sub.f (II)wherein R.sub.f is the same as defined above, X is a fluorine atom or a trifluoromethyl group and n is an integer of 1 to 10, which has good chemical, corrosion, solvent and oil resistance as well as water- and oil-repellence.
摘要:
Elastomeric copolymer of vinylidene fluoride and at least one other fluorine-containing monomer containing 28 to 92% by mole of the vinylidene fluoride unit and having an intrinsic viscosity of 0.4 to 1.3 at 35.degree. C. in methyl ethyl ketone, which is prepared by a two-stage polymerization process of vinylidene fluoride monomer and at least one other fluorine-containing monomer wherein monomers are copolymerized in an aqueous medium in the presence of a water-soluble radical polymerization initiator at a first stage to give a first stage-copolymer having an intrinsic viscosity of 0.01 to 3.0 at 35.degree. C. in methyl ethyl ketone and then copolymerized in an aqueous medium in the presence of the first stage-copolymer and an oil-soluble radical polymerization initiator at a second stage to give a second stage-copolymer, said elastomeric copolymer comprising 1 to 80% by weight of the first stage-copolymer and 20 to 99% by weight of the second stage-copolymer, process for preparing the same and composition containing the same. The elastomeric copolymer can be cured at satisfactory cure rate to give cured rubber having low compression set and high elongation.