Abstract: Aqueous microemulsions obtained from a perfluorinated alkane sulphonic or carboxylic acid or salt thereof, a liquid fluorinated monomer comprising a cure-site and optionally an inert liquid and highly fluorinated hydrocarbon compound. The aqueous microemulsion may be formed by mixing together water, a perfluorinated alkane sulphonic or carboxylic acid or salt thereof, optionally an inert liquid and highly fluorinated hydrocarbon compound and a liquid fluorinated monomer having a cure-site.

Abstract: A curable fluoroelastomer composition for preparing a perfluoroelastomer. The composition includes; (1) a perfluoropolymer having one or more cure-sites selected from a halogen capable of participating in peroxide cure reaction and/or nitrile groups; (2) an organic peroxide and/or a compound capable of effecting curing of the perfluoropolymer through said nitrile groups; and (3) optionally a polyunsaturated coagent. The perfluoropolymer in the composition is essentially free of ionic end groups and the total amount of metal cations in the composition is not more than 10 ?g/g perfluoropolymer. The perfluoroelastomers may be obtained from curing the composition in a sufficiently low amount of metal cations so as to make the fluoroelastomer suitable for use in the semi-conductor industry.

Abstract: High purity fluoropolymers are obtained by the emulsion polymerization process, removing essentially all ions and coagulating the polymer essentially without adding ions. These polymers are useful in the field of electronic devices.

Abstract: A fluoropolymer having a reduced amount of polar end groups. The fluoropolymer is produced by free radical polymerization of fluorinated monomers and the initiation of the polymerization is carried out in the presence of a chloride salt. Polar end groups include hydroxy groups and ionized or ionizable end groups. Examples of ionized or ionizable end groups include acid groups and salts thereof such as sulfonic acid and salts thereof, —CH2—OSO3H groups, sulfates and carbonyl containing end groups such as carboxylic and carboxylate groups. Due to the presence of chloride salt at the initiation of the free radical polymerization, CF2Cl end groups are formed instead of the polar end groups. As a result, a fluoropolymer is obtained that has improved processibility and heat resistance.

Abstract: High purity fluoropolymers are obtained by the emulsion polymerization process, removing essentially all ions and coagulating the polymer essentially without adding ions. These polymers are useful in the field of electronic devices.

Abstract: Aqueous microemulsions obtained from a perfluorinated alkane sulphonic or carboxylic acid or salt thereof, a liquid fluorinated monomer comprising a cure-site and optionally an inert liquid and highly fluorinated hydrocarbon compound. The aqueous microemulsion may be formed by mixing together water, a perfluorinated alkane sulphonic or carboxylic acid or salt thereof, optionally an inert liquid and highly fluorinated hydrocarbon compound and a liquid fluorinated monomer having a cure-site.

Abstract: High purity fluoropolymers are obtained by the emulsion polymerization process, removing essentially all ions and coagulating the polymer essentially without adding ions. These polymers are useful in the field of electronic devices.

Abstract: A curable fluoroelastomer composition for preparing a perfluoroelastomer. The composition includes; (1) a perfluoropolymer having one or more cure-sites selected from a halogen capable of participating in peroxide cure reaction and/or nitrile groups; (2) an organic peroxide and/or a compound capable of effecting curing of the perfluoropolymer through said nitrile groups; and (3) optionally a polyunsaturated coagent. The perfluoropolymer in the composition is essentially free of ionic end groups and the total amount of metal cations in the composition is not more than 10&mgr;g/g perfluoropolymer. The perfluoroelastomers may be obtained from curing the composition in a sufficiently low amount of metal cations so as to make the fluoroelastomer suitable for use in the semi-conductor industry.

Abstract: A fluoropolymer having a reduced amount of polar end groups. The fluoropolymer is produced by free radical polymerization of fluorinated monomers and the initiation of the polymerization is carried out in the presence of a chloride salt. Polar end groups include hydroxy groups and ionized or ionizable end groups. Examples of ionized or ionizable end groups include acid groups and salts thereof such as sulfonic acid and salts thereof, —CH2—OSO3H groups, sulfates and carbonyl containing end groups such as carboxylic and carboxylate groups. Due to the presence of chloride salt at the initiation of the free radical polymerization, CF2Cl end groups are formed instead of the polar end groups. As a result, a fluoropolymer is obtained that has improved processibility and heat resistance.

Abstract: Process for working up aqueous dispersions of fluoropolymers. Fluoropolymer dispersions, in particular of fluoroelasomers, can be coagulated without adding chemicals, by compression with the aid of a gas and release through one or more small apertures.

Abstract: A polymer processing aid composition, a melt processable polymer composition that uses the polymer processing aid, and a method of improving the melt processability of a thermoplastic polymer are provided. The polymer processing aid composition comprises a fluoropolymer that comprises interpolymerized units derived from a perfluorovinyl ether, preferably one having the formula CF2═CF—(OCF2CF(CF3))AORf where a has a value of 0 to 3 and Rf is a perfluoroaliphatic (preferably perfluoroalkyl or perfluoroalkoxy) having from 1 to 8 (preferably 1 to 3) carbon atoms.

Abstract: A polymer processing aid composition, a melt processable polymer composition that uses the polymer processing aid, and a method of improving the melt processability of a thermoplastic polymer are provided. The polymer processing aid composition comprises a multimodal fluoropolymer that preferably comprises interpolymerized units derived from an ethylenically unsaturated fluoromonomer tetrafluoroethylene and at least one ethylenically copolymerizable alpha-olefin monomer.