Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A membrane including a sheet of expanded polytetrafluoroethylene. The sheet is porous and has a gas permeability of at least 0.2 CFM according to ASTM D737 testing. The gas permeability of the membrane changes by less than 30% when the membrane is exposed to a temperature of 180° C. for a time of one hour. The sheet also has an average Mullen Hydrostatic Entry pressure of at least 135 psi according to ASTM D751 testing. The average Mullen Hydrostatic Entry pressure is substantially unchanged after exposure to a temperature of 180° C. for a time of one hour. The membrane has a bubble point value that changes by less than 20% when the membrane is exposed to a temperature of 180° C. for a time of one hour.

Abstract: 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.

Abstract: A filter assembly for use in a baghouse having a tubesheet with an opening therethrough. The filter assembly comprises a cage connectible with the tubesheet adjacent the opening. The cage includes wire members. A filter bag is supported by the wire members of the cage to maintain the filter bag in an operational condition and in fluid communication with the opening in the tubesheet. A reverse pulse jet cleaning system positioned to direct a cleaning pulse through the opening and into the filter bag for a plurality of cleaning cycles. The filter bag is made from laminated filter media. The laminated filter media includes a fabric substrate. The laminated filter media also includes a membrane laminated to the fabric substrate, the membrane comprising a single layer of expanded material of co-coagulated polytetrafluoroethylene with titanium dioxide particles. The titanium dioxide particles are present in the co-coagulated polytetrafluoroethylene in a range of about 0.5 wt % to 4.5 wt %.

Abstract: 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 ?m to about 1200 ?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 ?m.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A process of producing a multilayer polytetrafluoroethylene article includes filling a pre-form with two or more layers of a polytetrafluoroethylene fine powder, wherein at least one layer comprises a functional additive and at least one layer comprises a processing aid; disposing a separation layer between the two or more layers, wherein the separation layer is configured to provide structural integrity to each layer during filling; extruding the two or more layers to obtain a multilayer extrudate; removing the processing aid; and stretching the multilayer extrudate to form the multilayer polytetrafluoroethylene article.

Abstract: 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.

Abstract: 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 ?m to about 1200 ?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 ?m.

Abstract: 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.

Abstract: 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.

Abstract: A method of making an article having an improved oleophobic property. The method includes the step of providing a microprous membrane. The method also includes the step of laminating a porous fabric 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 provide a treated laminate. The treated laminate has an oil resistance property of at least a number 7 determined by AATCC 118 testing on both the membrane side and the fabric side. The laminate also has an air permeability therethrough of at least 0.01 CFM per square foot determined by ASTM D737 testing.

Abstract: 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.