Abstract: An emulsion polymerization process for the production of fluoroelastomers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X—Rf—(CH2)n—O—P(O)(OM)2, wherein n=1 or 2, X=H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of fluoroelastomers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X—Rf-(CH2)n—O—P(O)(OM)2, wherein n=1 or 2, X=H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of non-elastomeric fluoropolymers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X-Rf-(CH2)n—O—P(O)(OM)2, wherein n is 1 or 2, X?H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of fluoropolymers is disclosed wherein a combination of at least two fluorosurfactants is employed as dispersants. At least one fluorosurfactant is a perfluoroalkyl or perfluoroalkoxy sulfinate. At least one other fluorosurfactant is a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a slat thereof, sulfonic acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of non-elastomeric fluoropolymers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X-Rf-(CH2)n—O—P(O)(OM)2, wherein n is 1 or 2, X?H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of fluoroelastomers is disclosed wherein at least one fluorosurfactant is employed as dispersant, said fluorosurfactant being a fluoroalkylphosphoric acid ester of the formula X—Rf—(CH2)n—O—P(O)(OM)2, wherein n=1 or 2, X?H or F, M=a univalent cation, and Rf is a C4-C6 fluoroalkyl or fluoroalkoxy group. Optionally, a second dispersing agent may be employed in the polymerization, said second agent being a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a salt thereof, sulfonic acid and a salt thereof, phosphoric acid and a salt thereof.

Abstract: An emulsion polymerization process for the production of fluoropolymers that contain polymerized units of tetrafluoroethylene is disclosed wherein a perfluoroaliphatic sulfinate is employed as dispersant.

Abstract: An emulsion polymerization process for the production of fluoropolymers is disclosed wherein a combination of at least two fluorosurfactants is employed as dispersants. At least one fluorosurfactant is a perfluoroalkyl or perfluoroalkoxy sulfinate. At least one other fluorosurfactant is a perfluoropolyether having at least one endgroup selected from the group consisting of carboxylic acid, a slat thereof, sulfonic acid and a salt thereof.

Abstract: Perfluoroelastomers that contain high levels (i.e. about 40 mole percent or more) of perfluoro(alkyl vinyl ether) copolymerized units can form stable blends with higher levels of perfluoropolyethers than can perfluoroelastomers that contain lower levels of perfluoro(alkyl vinyl ether) units. Thus, the former blends have better low temperature properties than the latter.

Abstract: Perfluoroelastomer articles comprising perfluoroelastomers having copolymerized units of tetrafluoroethylene, a perfluoro(vinyl ether), and a nitrile-containing cure site monomer are at least partially cured and then exposed in air to temperatures between 150° and 350° C. for 1 to 70 hours in order to lighten the article's color and render it translucent or transparent. The resulting articles contain less than 200 ppm metals.

Abstract: Fast curing perfluoroelastomer compositions are provided which comprise a perfluoroelastomer having a plurality of nitrile groups and a plurality of carboxyl-containing groups, carboxylate-containing groups, carboxamide groups, or mixtures thereof; and an organotin curing agent.