Abstract: Process for reducing thermally induced discoloration of fluoropolymer resin produced by polymerizing fluoromonomer in an aqueous dispersion medium to form aqueous fluoropolymer dispersion and isolating said fluoropolymer from said aqueous medium to obtain said fluoropolymer resin. The process comprises: exposing the aqueous fluoropolymer dispersion to ultraviolet light in the presence of an oxygen source.

Abstract: Process for reducing thermally induced discoloration of fluoropolymer resin produced by polymerizing fluoromonomer in an aqueous medium to form aqueous fluoropolymer dispersion and isolating said fluoropolymer from said aqueous medium to obtain said fluoropolymer resin. The process comprises: exposing the fluoropolymer resin to fluorine.

Abstract: Process for reducing thermally induced discoloration of fluoropolymer resin produced by polymerizing fluoromonomer in an aqueous dispersion medium to form aqueous fluoropolymer dispersion and isolating said fluoropolymer from the aqueous medium by separating fluoropolymer resin in wet form from the aqueous medium and drying to produce fluoropolymer resin in dry form. The process comprises: pretreating the aqueous fluoropolymer dispersion and/or the fluoropolymer resin in wet or dry form; and exposing the fluoropolymer resin in dry form to fluorine.

Abstract: A process for reducing thermally induced discoloration of fluoropolymer resin produced by polymerizing fluoromonomer in an aqueous dispersion medium to form aqueous fluoropolymer dispersion and isolating said fluoropolymer from the aqueous medium to obtain the fluoropolymer resin. The process comprises: exposing the aqueous fluoropolymer dispersion to oxidizing agent.

Abstract: Process for reducing thermally induced discoloration of fluoropolymer resin produced by polymerizing fluoromonomer in an aqueous dispersion medium to form aqueous fluoropolymer dispersion and isolating said fluoropolymer from said aqueous medium to obtain said fluoropolymer resin. The process comprises: adjusting the pH of the aqueous medium of the aqueous fluoropolymer dispersion to greater than about 8.5; and exposing said aqueous fluoropolymer dispersion to an oxygen source.

Abstract: A process is provided for polymerizing fluoromonomer in an aqueous medium, wherein a dispersion of essentially surfactant-free hydrocarbon-containing oleophilic nucleation sites is first formed in the aqueous medium, and then polymerization is commenced to form a dispersion of fluoropolymer particles at the oleophilic nucleation sites, wherein the nucleation sites can be derived from hydrocarbon-containing compound. The surfactant used to stabilize the fluoropolymer dispersion can also be hydrocarbon-containing.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A polymerization process is provided, comprising polymerizing fluoromonomer in an aqueous medium to form a dispersion of fluoropolymer particles in the aqueous medium, said polymerizing being carried out in the presence of (i) polymerization initiator, and (ii) hydrocarbon-containing surfactant stabilizing the dispersion of fluoropolymer particles, the hydrocarbon-containing surfactant being passivated to reduce its the telogenic behavior.

Abstract: A process is provided for the polymerization of fluoromonomer to an dispersion of fluoropolymer particles in an aqueous medium in a polymerization reactor, by (a) providing the aqueous medium in the reactor, (b) adding the fluoromonomer to the reactor, (c) adding initiator to the aqueous medium, the combination of steps (b) and (c) being carried out essentially free of hydrocarbon-containing surfactant and resulting in the kickoff of the polymerization of the fluoromonomer, and (d) metering hydrocarbon-containing surfactant into the aqueous medium after the kickoff of polymerization, e.g. after the concentration of the fluoropolymer in the aqueous medium is at least 0.6 wt %, the metering being at a rate reducing the telogenic activity of said surfactant while maintaining surface activity.

Abstract: A process is provided for polymerizing fluoromonomer in an aqueous medium, wherein a dispersion of essentially surfactant-free hydrocarbon-containing oleophilic nucleation sites is first formed in the aqueous medium, and then polymerization is commenced to form a dispersion of fluoropolymer particles at the oleophilic nucleation sites, wherein the nucleation sites can be derived from hydrocarbon-containing compound. The surfactant used to stabilize the fluoropolymer dispersion can also be hydrocarbon-containing.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A composition comprising a mixture of fluoropolyether acids or salts having a number average value of about 800 to about 2500 g/mol. The amount of fluoropolyether acids or salt in the mixture having a molecular weight of not more than 500 g/mol is not more than 50 ppm by weight of the total amount of fluoropolyether acids or salts in the mixture. The amount of fluoropolyether acids or salts in the mixture having a molecular weight of 2500 g/mol or greater is not more than 40% by weight of the total amount of fluoropolyether acids or salts in the mixture. Preferably the fluoropolyether acids or salts comprise an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion and phosphonate. Also disclosed is an aqueous dispersion polymerization process for fluoropolymer manufacture employing polymerization agent comprising the specified mixture of fluoropolyether acids or salts.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A process for polymerizing at least one fluorinated monomer in an aqueous polymerization medium in the presence of initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer having a fluoropolymers solids content of at least about 10% by weight. The polymerization agent is a combination of fluoropolyether acid or salt thereof and siloxane surfactant. The aqueous polymerization medium contains less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactants.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluoropolyether acid or salt surfactant.

Abstract: A process for polymerizing at least one fluorinated monomer in an aqueous medium in the presence of initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer having a fluoropolymers solids content of at least about 10% by weight. The polymerization agent is a combination of fluoropolyether acid or salt thereof and hydrocarbon surfactant. The aqueous medium contains less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactants. The process is preferably performed without adding polymer seed prior to polymerization kick-off.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?]Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.

Abstract: A process comprising polymerizing at least one fluorinated monomer in an aqueous medium containing initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, the polymerization agent comprising: fluoropolyether acid or salt thereof having a number average molecular weight of at least about 800 g/mol; and fluorosurfactant having the formula: [R1—On-L-A?] Y+ wherein: R1 is a linear or branched partially or fully fluorinated aliphatic group which may contain ether linkages; n is 0 or 1; L is a linear or branched alkylene group which may be nonfluorinated, partially fluorinated or fully fluorinated and which may contain ether linkages; A? is an anionic group selected from the group consisting of carboxylate, sulfonate, sulfonamide anion, and phosphonate; and Y+ is hydrogen, ammonium or alkali metal cation; with the proviso that the chain length of R1—On-L- is not greater than 6 atoms.