Compositions for compounding, extrusion and melt processing of foamable and cellular fluoropolymers

A perfluoropolymer pellet composition comprising:

• one or more base perfluoropolymers comprising at least 50 percent by weight of said composition, wherein each of said perfluoropolymers is selected from the group consisting of tetrafluoroethylene/perfluoromethylvinyl ether copolymer (MFA), hexafluoropropylene/tetrafluoroethylene copolymer (FEP) and perfluoroalkoxy (PFA) and any blend thereof, and talc loaded in said one or more base perfluoropolymers in a range of 3 percent to about 15 percent by weight of said composition, wherein said one or more base perfluoropolymers are melt-processable at elevated temperatures of at least about 600° F. at which talc acts as a chemical foaming agent for heat extrusion or mold processing of said composition to form cellular or foamed or blown articles having uniform cell structure,
• wherein hydrogen-containing fluoropolymers are absent from the composition.

A foamable composition comprising:

• at least one base per(halo)fluoropolymer comprising than at least 50 percent by weight of said composition and a chemical foaming agent consisting of talc blended in said at least one base per(halo)fluoropolymer, wherein said at least one base per(halo)fluoropolymer is selected from the group consisting of tetrafluoroethylene/perfluoromethylvinyl ether copolymer (MFA), hexafluoropropylene/tetrafluoroethylene copolymer (FEP) and perfluoroalkoxy (PFA) and any blend thereof,
• wherein said talc comprises about 5 percent to about 15 percent by weight of said composition, and wherein said per(halo)fluoropolymer is melt-processable at an elevated temperature of at least about 600° F. at which said talc functions as a chemical foaming agent for extrusion or mold processing of the composition into a foamed article having uniform cell structure, wherein hydrogen-containing fluoropolymers are absent from the composition.

A cellular material formed by

• providing pellets comprising one or more perfluoropolymers including at least 50 percent by weight of said pellets and talc blended with said one or more perfluoropolymers, said talc comprising 3 percent to about 15 percent by weight of said pellets, wherein each of said perfluoropolymers is selected from the group consisting of tetrafluoroethylene/perfluoromethylvinyl ether copolymer (MFA), hexafluoropropylene/tetrafluoroethylene copolymer (FEP) and perfluoroalkoxy (PFA) and any blend thereof,
• wherein hydrogen-containing fluoropolymers are absent from the pellets, heating said pellets to a temperature of at least about 600° F. at which said talc functions as a chemical foaming agent to form a foamed article having uniform cell structures.