E.i. Dupont De Nemours and Company

The Chemours Company Fc, LLC

Sharon Ann Libert

Ralph Munson Aten

Jon Lee Howell

Keith Ward Hutchenson

Heidi Elizabeth Burch

Xian Liang

Hans Schonemann

Val J Krukonis

Hans Jurgen Schonemann

This disclosure relates to a process for extracting a perfluoropolyether. The process involves: (a) contacting a solvent comprising a liquid or supercritical carbon dioxide with a lubricating grease comprising a thickener and the perfluoropolyether in an extraction zone to form an extraction solution comprising an extracted perfluoropolyether; and (b) recovering the extracted perfluoropolyether from the extraction solution; wherein the recovered extracted perfluoropolyether comprises no more than about 2 wt % of the thickener.

Perfluoropolyether extraction processes

This disclosure relates to a process for extracting a perfluoropolyether. The process involves: (a) contacting a solvent comprising a liquid or supercritical carbon dioxide with a lubricating grease comprising a thickener, an extraction aid material, and the perfluoropolyether in an extraction zone to form an extraction solution comprising an extracted perfluoropolyether; and (b) recovering the extracted perfluoropolyether from the extraction solution; wherein the recovered extracted perfluoropolyether comprises no more than about 2 wt % of the thickener.

Recovery of perfluorinated polyether oils from grease matrices incorporating extraction aids by carbon dioxide extraction

A process is provided for extruding a partially crystalline melt-fabricable perfluoropolymers. The process comprises blow molding from a perfluoropolymer having polytetrafluoroethylene sub-micrometer particles dispersed therein. The perfluoropolymer composition is a core/shell polymer, with pelletized blend, a dispersion blend or a melt-mixed polymer.

Core/shell polymer and fluoropolymer blending blow molding and blown film process

Tensile strength after heat aging of articles molded from melt-fabricable perfluoropolymer is improved by incorporating polytetrafluoroethylene as dispersed submicrometer-size particles into the melt-fabricable perfluoropolymer.

Heat aged perfluoropolymer

Modified polytetrafluoroethylene powder of a sinterable copolymer of tetrafluoroethylene containing about 0.5 to about 10 weight % of fluorinated vinyl ether, the copolymer having a melt creep viscosity of greater than about 1&#xd7;10Pa&#xb7;S. In preferred embodiments, the sinterable copolymer has a melt creep viscosity of greater than about 1&#xd7;10Pa&#xb7;S and fluorinated vinyl ether content of from about 1 to about 7 weight %. The polymer has a combination of a high level of fluorinated vinyl ether and a melt creep viscosity which is high enough to enable the fabrication of articles by sintering.

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Hockessin, DE, United States of America

Sharon Ann Libert