摘要:
A fluoroelastomer composition comprising (a) a fluoroelastomer having stabilized end group derived from an isoparaffin selected from the group consisting of isobutane, isopentane and isohexane, (b) at least one member selected from the group consisting of bivalent metal oxides, bivalent metal hydroxides and mixtures of bivalent metal oxide or metal hydroxide with metal salt of weak acid, (c) an aromatic polyhydroxy compound and (d) a quaternary ammonium compound of 8-alkyl- (or 8-aralkyl-)1,8-diazabicyclo[5.4.0]-7-undecenium, provides a fluoro-rubber having low compression set and excellent elastic properties and has excellent processing and storage properties. The fluoroelastomer can be cured with appropriate induction time and fast cure rate by the use of a specific curing agent system mentioned above.
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 copolymer comprising repeating units derived from tetrafluoroethylene, vinylidene fluoride and hexafluoropropylene in a molar ratio within an area defined on a tetrafluoroethylene, vinylidene fluoride and hexafluoropropylene ternary composition diagram by a hexagon with its first vertex A at 34.0% by weight of tetrafluoroethylene, 8.5% by weight of vinylidene fluoride and 57.5% by weight of hexafluoropropylene; its second vertex B at 26.5% by weight of tetrafluoroethylene, 14.5% by weight of vinylidene fluoride and 59.0% by weight of hexafluoropropylene; its third vertex C at 31.0% by weight of tetrafluoroethylene, 24.0% by weight of vinylidene fluoride and 45.0% by weight of hexafluoropropylene; its fourth vertex D at 49.0% by weight of tetrafluoroethylene, 26.5% by weight of vinylidene fluoride and 24.5% by weight of hexafluoropropylene; its fifth vertex E at 49.0% by weight of tetrafluoroethylene, 11.0% by weight of vinylidene fluoride and 40.0% by weight of hexafluoropropylene; and its sixth vertex F at 50.0% by weight of tetrafluoroethylene, 9.0% by weight of vinylidene fluoride and 41.0% by weight of hexafluoropropylene having not only good flexibility, heat resistance and flame retardance but also good insulating performance and moldability.
摘要:
A cross-linkable coating composition comprising a fluorine-containing elastomeric copolymer which comprises (a) 50 to 95% by mole of repeating units derived from a fluoroolefin of the formula:CF.sub.2 .dbd.CXY (I)wherein X and Y are the same or different and a fluorine atom or a chlorine atom, (b) 50 to 5% by mole of repeating units derived from a perfluorovinyl ether of the formula:R.sub.f --[OCFZCF.sub.2 (CF.sub.2).sub.m ].sub.n --OCF.dbd.CF.sub.2 (II)wherein R.sub.f is a C.sub.1 -C.sub.6 perfluoroalkyl group, Z is a fluorine atom or a trifluoromethyl group, n is an integer of 0 to 5 and m is 0 to 1 provided that when m is 1 (one), X is not a trifluoromethyl group and a cross-linking agent for the copolymer, the copolymer and the cross-linking agent being dissolved or dispersed in a fluorosolvent is provided.
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.
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 fluoropolymer comprising 12 to 50% by mole of repeating units derived from a perfluorovinyl ether of the formula:CF.sub.2 .dbd.CFO--(CF.sub.2 CFXO).sub.m --R.sub.f (I)wherein R.sub.f is a C.sub.1 -C.sub.6 perfluoroalkyl group, X is a fluorine atom or a trifluoromethyl group and m is an integer of 1 to 5, 50 to 88% by mole of repeating units derived from tetrafluoroethylene and 0.1 to 5% by mole of repeating units of hexafluoropropylene having improved strength and compression set.
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:
A fluoroelastomer composition comprising a fluoroelastomer, an acid acceptor and a hydrofluoric acid salt of 4,4'-alkylenebis(cyclohexylamine) as a curing agent, which has an excellent scorching resistance and an excellent curing reactivity.