Abstract: 2,2-diphenylhexafluoropropanes are prepared by condensation reaction of benzene or benzenes substituted with a halogen atom or atoms, a lower alkyl group or groups or a hydroxyl group or groups with hexafluoroacetone in the presence of trifluoromethane sulfonic acid. Among the 2,2-diphenylhexafluoropropanes, 2,2-diphenylhexafluoropropane and 2,2-bis(p-chlorophenyl)hexafluoropropane are novel compounds.

Abstract: A fluorine rubber composition comprising a fluorine rubber and a polyfluoroalkyl group-containing block isocyanate compound represented by the following general formula:Rf(CH.sub.2)nXCONHRNHCOO(N.dbd.C--R.sup.2)mR.sup.1where Rf is a polyfluoroalkyl group having 4 to 20 carbon atoms; R is a divalent organic group; R.sup.1 is a lower alkyl group or phenyl group; R.sup.2 is a lower alkyl group; X is NH or O; n is an integer of 1 to 4 and m is 0 or 1, has a good vulcanization bond to metals without any substantial decrease in the rubber stretchability properly owned by the fluorine rubber.

Abstract: A perfluoro unsaturated nitrile compound represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)CNis produced by reaction of chlorine or bromine to a perfluoro unsaturated carboxylic acid ester represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)COORfollowed by reaction with ammonia, thereby converting the ester group to an acid amide group, and then conducting a dehydration reaction and a dehalogenation reaction of the resulting perfluoro unsaturated carboxylic acid amide represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)CONH.sub.2in any desired sequence, and is effectively applied as a cross-linking site monomer for fluorine-containing elastomers.

Abstract: A fluorine-containing copolymer composition comprises a novel terpolymer of tetrafluoroethylene-perfluoro(methylvinylether)-1,1,3,3,3-pentafluoroprope ne and dialkali metal salt of bisphenol compound gives a vulcanization product having a low compression set.

Abstract: A perfluoro unsaturated nitrile compound represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)CNis produced by reaction of chlorine or bromine to a perfluoro unsaturated carboxylic acid ester represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)COORfollowed by reaction with ammonia, thereby converting the ester group to an acid amide group, and then conducting a dehydration reaction and a dehalogenation reaction of the resulting perfluoro unsaturated carboxylic acid amide represented by the following general formula:CF.sub.2 .dbd.CFO(CF.sub.2)nOCF(CF.sub.3)CONH.sub.2in any desired sequence, and is effectively applied as a cross-linking site monomer for fluorine-containing elastomers.

Abstract: A fluorine-containing elastomer composition, which comprises a terpolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) and cyano group-containing (perfluorovinylether) represented by the following general formula:CF.sub.2 .dbd.CF?OCF.sub.2 CF(CF.sub.3)!nCNwherein n is an integer of 1 to 5, and a bis(aminophenyl) compound represented by the following general formula as a cross-linking agent: ##STR1## , wherein A is, for example, an alkylidene group, and X and Y are a hydroxyl group or an amino group, can produce vulcanized products having a good heat resistance and good physical properties, and the bis(aminophenyl) compound has no problem as to its safety.

Abstract: 2,2-bis(4-aminophenyl)hexafluoropropane is allowed to react with potassium thiocyanate and bromine to obtain 2,2-bis(5-amino-4,6-benzothiazolyl)hexafluoropropaneo which is allowed to further react successively with potassium hydroxide and hydrochloric acid to obtain 2,2-bis(4-amino-3-mercapto-phenyl)hexafluoropropane, which is a novel compound applicable as a curing agent for a fluorine-containing elastomer having CN groups as cross-linkable groups.

Abstract: Perfluoroalkyleneethertriazine oligomer obtained by reacting a dinitrile compound NC--Ff.sup.0 --CN, where Ff.sup.0 is --(CFXOCF.sub.2)a(CF.sub.2)b(CF.sub.2 OCFX)c--, where X is a fluorine atom or a CF.sub.3 group, a is an integer of 1 to 5, b is an integer of 1 to 2 and c is an integer of 1 to 5, or Rf.sup.0 is --CF.sub.2 O(CF.sub.2 O)dCF.sub.2 --, where d is an integer of 1 to 8, with ammonia, further reacting the resulting diamizine compound with a dinitrile compound NC--Rf.sup.1 --CN, Rf.sup.1 has the same meaning as that for Rf.sup.0 or Rf.sup.1 is a perfluoroalkylene group having 4 to 8 carbon atoms thereby obtaining a perfluoroalkyleneetherpolyimidoylamizine oligomer, then reacting the resulting oligomer with a perfluoronitrile compound Rf.sup.2 CN, Rf.sup.2 is CF.sub.3 (OCF.sub.2).sub.e -- where e is an integer of 3 to 10 thereby treating the terminal groups thereof, and then subjecting the resulting terminal-treated oligomer to a ring-closing reaction with a perfluoroacylating agent RF.sup.3 COY, Rf.

Abstract: A perfluoro unsaturated nitrile compound represented by the following general formula:CF.sub.2 =CFO(CF.sub.2)nOCF(CF.sub.3)CNis produced by reaction of chlorine or bromine to a perfluoro unsaturated carboxylic acid ester represented by the following general formula:CF.sub.2 =CFO(CF.sub.2)nOCF(CF.sub.3)COORfollowed by reaction with ammonia, thereby converting the ester group to an acid amide group, and then conducting a dehydration reaction and a dehalogenation reaction of the resulting perfluoro unsaturated carboxylic acid amide represented by the following general formula:CF.sub.2 =CFO(CF.sub.2)nOCF(CF.sub.3)CONH.sub.2in any desired sequence, and is effectively applied as a cross-linking site monomer for fluorine-containing elastomers.

Abstract: 2,2-bis(4-aminophenyl)hexafluoropropane is allowed to react with potassium thiocyanate and bromine to obtain 2,2-bis (5-amino-4,6-benzothiazolyl)hexafluoropropane, which is allowed to further react successively with potassium hydroxide and hydrochloric acid to obtain 2,2-bis(4-amino-3-mercaptophenyl)hexafluoropropane, which is a novel compound applicable as a curing agent for a fluorine-containing elastomer having CN groups as cross-linkable groups.

Abstract: A fluorine-containing elastomer composition comprising a fluorine-containing elastomer having a cyano group as a cross-linking agent and a bisamidoxime compound represented by the following general formula as a vulcanizing agent: ##STR1## where n is an integer of 1 to 10, gives vulcanization products having a satisfactory compression set without any problem of processability such as roll kneadability, etc. during the heading or during the vulcanization of the fluorine-containing elastomer having a cyano group as a cross-linkable group.

Abstract: A fluorine-containing elastomer composition comprising a fluorine-containing elastomer having a cyano group as a cross-linkable group and a bisamidrazone compound represented by the following general formula as a vulcanizing agent: ##STR1## wherein Rf is one of the following groups:(CF.sub.2).sub.n, CFX(OCF.sub.2 CFX).sub.m O(CF.sub.2).sub.nandCFX(OCF.sub.2 CFX).sub.p O(CF.sub.2).sub.n O(CFXCF.sub.2 O).sub.q CFXhas considerably improved roll kneadability and processability during the vulcanization-molding, and gives vulcanization products having good heat resistance and solvent resistance.

Abstract: When a novel bisamidoxime compound represented by the following general formula: ##STR1## where R is an alkylidene group having 1 to 6 carbon atoms, or a perfluoroalkylidene group having 1 to 10 carbon atoms, is used as a vulcanizing agent for fluorine-containing elastomers having cyano groups as cross-linkable groups, the resulting vulcanizates having a satisfactory compression set are obtained without any problem of processability such as roll kneadability, etc.

Abstract: A novel bifunctional vinyl ether compound having an aromatic ring, represented by the following general formula: ##STR1## where X is a halogen atom and n is an integer of 1 to 5, effective as a copolymer component for fluorine-containing elastomers is produced by adding a chlorine atom or a bromine atom (Y) to CF.sub.2 .dbd.CFO(CF.sub.2)nCOOR, where R is a lower alkyl group, then subjecting the resulting CF.sub.2 YCFYO(CF.sub.2)nCOOR to hydrolysis and acid chloridation, followed by reaction with monohalogenobenzene, reaction with SF.sub.4 to convert --CO-- to --CF.sub.2 --, and dechlorination or debromination, or by subjecting CF.sub.2 .dbd.CFO (CF.sub.2)nCOOR to hydrolysis and acid chloridation, followed by reaction with monohalogenobenzene and reaction with SF, to convert --CO-- to --CF.sub.2 --.

Abstract: Novel compound, 2,2-bis(4-carboxyphenyl)hexafluoropropane bisamidrazone, obtained by conversion of the carboxy groups of 2,2-bis(4-carboxyphenyl)hexafluoropropane to acid chloride groups, followed by reaction with ammonia; dehydration reaction of the resulting 2,2-bis(4-carboxyphenyl)hexafluoropropane diamide; reaction of the thus obtained 2,2-bis(4-cyanophenyl)hexafluoropropane with alcohol; and reaction of the resulting 2,2-bis(4-carboxyphenyl)hexafluoropropane bisiminoalkyl ether with hydrazine is a useful vulcanizing agent for fluorine-containing elastomer having cyano group.

Abstract: A fluoroelastomer having a copolymer composition comprising 50 to 80% by mole of tetrafluoroethylene, 20 to 45% by mole of perfluoro(lower alkyl vinyl ether) and 0.1 to 2% by mole of perfluoro(allylbenzene), the sum total being 100% by mole, and an intrinsic viscosity of 0.1 to 2.0 dl/g has a good vulcanization rate.

Abstract: A fluorine rubber composition comprising a fluorine rubber and a polyfluoroalkyl group-containing block isocyanate compound represented by the following general formula:Rf(CH.sub.2)nXCONHRNHCOO(N.dbd.C--R.sup.2)mR.sup.1where Rf is a polyfluoroalkyl group having 4 to 20 carbon atoms; R is a divalent organic group; R.sup.1 is a lower alkyl group or phenyl group; R.sup.2 is a lower alkyl group; X is NH or O; n is an integer of 1 to 4 and m is 0 or 1, has a good vulcanization bond to metals without any substantial decrease in the rubber stretchability properly owned by the fluorine rubber.

Abstract: A fluorine-containing elastomer composition comprising a terpolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) and cyano group-containing (perfluorovinylether), and a less expensive of the ammonium salt of organic or inorganic acid as a curing agent produce a vulcanization product having good heat resistance and solvent resistance, and when no carbon black, etc. are contained in the composition for curing, transparent vulcanization product having satisfactory physical properties are obtainable.

Abstract: A vulcanizable, fluorine-containing elastomer composition, which comprises a fluorine-containing elastomer containing at least one of iodine and bromine in the molecule, salicylaldo-imino copper complex having the following formula: ##STR1## as a cross-linking agent, and a polyfunctional unsaturated compound as a cross-linking aid can produce vulcanized products having a largely improved modulus of elasticity.

Abstract: A fluorine-containing-copolymer composition comprises a novel terpolymer of tetrafluoroethylene-perfluoro (methylvinylether)-1,1,3,3,3-pentafluoropropene and dialkali metal salt of bisphenol compound gives a vulcanization product having a low compression set.