General Electric Company

Bha Altair. LLC

Bha Group, Inc.

Gopakumar Thottupurathu

Martin Gregory Hatfield

Nusrat Farzana

A membrane comprises a sheet of expanded polytetrafluoroethylene. The sheet includes a first extrudate made from a first PTFE fine powder resin mixed with processing lubricant at a first lube rate. A second extrudate is made from the first PTFE fine powder resin mixed with processing lubricant at the first lube rate. The first and second extrudates combined into an integrated tape structure that is stretched in first and second directions. The sheet is porous and has a gas permeability of at least 0.1 CFM according to ASTM D737. The sheet has an average Mullen Hydrostatic Burst pressure in the range of 135 psi to 175 psi according to ASTM D751.

Porous membrane

Method of making a oleophobic layer on a fluoropolymer (e.g., polytetrafluoroethylene (PTFE)). The oleophobic layer includes a fluoroalkyl acrylate copolymer. The fluoropolymer may be an expanded PTFE formed into a porous membrane. The oleophobicity may be sufficient to repel #8 oil (n-heptane) in accordance with AATCC Test Method 118. There are also coated articles including fluoropolymers and oleophobic layers made from fluoroalkyl acrylate copolymers.

Process to increase the oleophobicity of PTFE, and resulting oleophobic articles

The present application thus provides a composite composition comprising PTFE and zeolite. According to another aspect, the present application provides a method for making a composite article comprising bonding zeolite to PTFE. According to still yet another aspect of the present application, a method for separating components of the mixture comprising contacting the mixture with a composite composition comprising PTFE and zeolite is disclosed.

Poly(tetrafluoroethylene) zeolite composite and methods

A method of making a porous membrane includes, in an exemplary embodiment, mixing together a first fine powder PTFE resin and a second fine powder PTFE resin to form a PTFE resin mixture. The first PTFE resin having a characteristic of forming more and longer fibrils than fibrils formed from the second PTFE resin. The second PTFE resin having a characteristic of forming thicker nodes than nodes formed from the first PTFE resin. The method also includes forming a preform from the PTFE resin mixture, extruding the preform into a tape, passing the tape through a plurality of opposing calender rolls to form a calendered tape having a thickness of about 380 &#x3bc;m to about 1200 &#x3bc;m, and stretching the calendered tape in the transverse direction to form a porous membrane having a plurality of nodes and fibrils and having a thickness of at least about 100 &#x3bc;m.

Expanded PFTE membrane and method of making

An article includes a microporous membrane. A porous fabric is laminated to the microporous membrane to form a laminate with a membrane side and a fabric side. A treatment material is applied to the laminate to form a treated laminate. The treated laminate having an oil resistance of at least a number 7 determined by AATCC 118 testing on both the membrane side and the fabric side. The treated laminate also has an air permeability through the treated laminate of at least 0.01 CFM per square foot determined by ASTM D737 testing.

Oleophobic laminated article

Method for making a mixture used in the production of a polytetrafluoroethylene (PTFE) membrane including porous inorganic materials. The mixture includes PTFE resin, a lubricating agent, and a porous inorganic material. The mixture may be further processed to form a PTFE membrane.

Methods of making a mixture for a PTFE membrane with inorganic materials, and compositions related thereto

Method for making a mixture used in the production of a polytetrafluoroethylene (PTFE) membrane including metal oxide(s). The mixture includes PTFE resin, a lubricating agent, and a metal oxide. The mixture may be further processed to form a PTFE membrane.

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Overland Park, KS, United States of America

Gopakumar Thottupurathu