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: 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 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 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 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 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: The present invention relates to the reduction of oligomer content of melt-processible fluoropolymer so that the fluoropolymer has at least 25 ppm less oligomer than the as-polymerized fluoropolymer.

Abstract: The present invention relates to the reduction of oligomer content of melt-processible fluoropolymer so that the fluoropolymer has at least 25 ppm less oligomer than the as-polymerized fluoropolymer.

Abstract: The present invention relates to the reduction of oligomer content of melt-processible fluoropolymer so that the fluoropolymer has at least 25 ppm less oligomer than the as-polymerized fluoropolymer, the reduction being obtained by melting the fluoropolymer forming a surface of molten fluoropolymer and regenerating this surface, contacting the regenerating surface with inert gas, and devolatilizing the resultant molten fluoropolymer.

Abstract: Chemical reactions are carried out with molten fluoropolymer, most conveniently in an extruder, wherein the reaction zone in the extruder is isolated from the melting zone, and the molten fluoropolymer is subdivided in the reaction zone sufficiently that contact and reaction between the reactant and the molten fluoropolymer in the reaction zone is essentially free of mass transfer limitation, followed by devolatilization in isolation from the reaction zone, and cooling the devolatilized fluoropolymer.

Abstract: Chemical reactions are carried out with molten fluoropolymer, most conveniently in an extruder, wherein the reaction zone in the extruder is isolated from the melting zone, and the molten fluoropolymer is subdivided in the reaction zone sufficiently that contact and reaction between the reactant and the molten fluoropolymer in the reaction zone is essentially free of mass transfer limitation, followed by devolatilization in isolation from the reaction zone, and cooling the devolatilized fluoropolymer.

Abstract: Chemical reactions are carried out with molten fluoropolymer, most conveniently in an extruder, wherein the reaction zone in the extruder is isolated from the melting zone, and the molten fluoropolymer is subdivided in the reaction zone sufficiently that contact and reaction between the reactant and the molten fluoropolymer in the reaction zone is essentially free of mass transfer limitation, followed by devolatilization in isolation from the reaction zone, and cooling the devolatilized fluoropolymer.

Abstract: Chemical reactions are carried out with molten fluoropolymer, most conveniently in an extruder, wherein the reaction zone in the extruder is isolated from the melting zone, and the molten fluoropolymer is subdivided in the reaction zone sufficiently that contact and reaction between the reactant and the molten fluoropolymer in the reaction zone is essentially free of mass transfer limitation, followed by devolatilization in isolation from the reaction zone, and cooling the devolatilized fluoropolymer.