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: Process for polymerizing fluoromonomer to form an aqueous dispersion of fluoropolymer particles including: (a) providing an aqueous medium in a polymerization reactor, (b) adding nucleating additive comprising polyalkylene oxide having a number average molecular weight of about 50 to about 2000 to the aqueous medium in an amount of about 0.1 ppm to about 50 ppm based on water in the aqueous medium, (c) exposing the nucleating additive to oxidizing agent to form a dispersion of oleophilic nucleation sites in the aqueous medium; (d) pressurizing the reactor by adding fluoromonomer, and (e) adding polymerization initiator to the aqueous medium to cause the polymerizing of the fluoromonomer to form fluoropolymer particles dispersed in the aqueous medium.

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 the 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: exposing the fluoropolymer resin in wet or dry form to oxidizing agent.

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 the fluoropolymer from the aqueous medium to obtain fluoropolymer resin. The process comprises: contacting the aqueous fluoropolymer dispersion with sorbent.

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 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 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: Process for reducing thermally induced discoloration of melt-processible 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: melt extruding said fluoropolymer resin to produce molten fluoropolymer resin; and exposing said molten fluoropolymer resin to an oxygen source during said melt extruding.

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: 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 oxidizing agent selected from the group consisting of hypochlorite salts and nitrite salts.

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 hydrogen peroxide.

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 fluoropolymer from said aqueous medium by separating wet fluoropolymer resin from the aqueous medium and drying to produce fluoropolymer resin. The process comprises: exposing the wet fluoropolymer resin to an oxygen source during drying.

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: 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: 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: 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 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: 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: heating the fluoropolymer resin to a temperature of about 160° C. to about 400° C.; and exposing the heated fluoropolymer resin to an oxygen source.

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 light having a wavelength of 10 nm to 760 nm in the presence of an oxygen source and photocatalyst.

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.