Abstract: A method of forming an unsintered biaxially expanded PTFE/thermoplastic polymer composite membrane is provided. The method includes blending fibrillatable polytetrafluoroethylene (PTFE) particles and thermoplastic polymer particles where the melting point of the thermoplastic polymer particles is less than the melting point of the fibrillatable PTFE particles. The method further includes forming the blend into a tape and expanding and heating the tape in a first direction at a first temperature. The expanded tape is then expanded, either concurrently or sequentially in a second direction to form an ePTFE composite membrane. The method does not include a sintering temperature. The ePTFE particles and thermoplastic polymer particles have an average particle size of less than 1 ?m. In addition, the ePTFE composite membrane has a geometric mean matrix modulus to geometric mean matrix tensile strength ratio of at least about 6 and an absolute dimensional change percentage of less than about 1.5%.

Abstract: A tetrafluoroethylene (TFE) copolymer film having a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. is provided. In exemplary embodiments, the third endotherm is approximately 380° C. In some embodiments, the second endotherm is between about 320° C. and about 330° C. or between about 330° C. and about 350° C. TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. In addition, the dense articles have a void volume of less than about 20%. Methods for dense articles from core shell tetrafluoroethylene copolymers are also provided. The dense articles exhibit improved physical and mechanical properties such as adhesion and barrier properties.

Abstract: A tetrafluoroethylene (TFE) copolymer film having a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. is provided. In exemplary embodiments, the third endotherm is approximately 380° C. In some embodiments, the second endotherm is between about 320° C. and about 330° C. or between about 330° C. and about 350° C. TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. In addition, the dense articles have a void volume of less than about 20%. Methods for dense articles from core shell tetrafluoroethylene copolymers are also provided. The dense articles exhibit improved physical and mechanical properties such as adhesion and barrier properties.

Abstract: A method of fabricating low EW, water insoluble electrolyte materials includes providing a perfluorinated polymer resin that includes perfluorinated carbon-carbon backbone chain and sulfonyl fluoride ended perfluorinated side chains, extending from the perfluorinated backbone chains via an ether linkage, exposing the perfluorinated polymer resin to ammonia gas to convert the sulfonyl fluoride groups to sulfonamide groups, —SO2—NH2, which reacts with sulfonyl fluoride containing chemical agent(s) to form sulfonimide groups, and at the same time, generates low EW, 3-dimensional cross-linked, water-insoluble perfluorinated polymer electrolyte materials.

Abstract: A tetrafluoroethylene (TFE) copolymer film having a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. is provided. In exemplary embodiments, the third endotherm is approximately 380° C. In some embodiments, the second endotherm is between about 320° C. and about 330° C. or between about 330° C. and about 350° C. TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. In addition, the dense articles have a void volume of less than about 20%. Methods for dense articles from core shell tetrafluoroethylene copolymers are also provided. The dense articles exhibit improved physical and mechanical properties such as adhesion and barrier properties.

Abstract: A dense article that includes a dense TFE copolymer film is provided. The dense TFE copolymer film includes a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. To form the dense article, a core shell TFE copolymer is formed into a pellet, ram extruded into a tape, dried into a dried preform, and then stretched into a dense TFE copolymer film that exhibits improved physical and mechanical properties. The dense TFE copolymer film is produced directly from the dried preform at a deformation temperature less than about 335° C. and without increasing the porosity of the dried preform, as would conventionally be done in expansion processes. The dense TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. The dense articles have a void volume less than about 20%.

Abstract: A dense article that includes a dense TFE copolymer film is provided. The dense TFE copolymer film includes a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. To form the dense article, a core shell TFE copolymer is formed into a pellet, ram extruded into a tape, dried into a dried preform, and then stretched into a dense TFE copolymer film that exhibits improved physical and mechanical properties. The dense TFE copolymer film is produced directly from the dried preform at a deformation temperature less than about 335° C. and without increasing the porosity of the dried preform, as would conventionally be done in expansion processes. The dense TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. The dense articles have a void volume less than about 20%.

Abstract: A method of fabricating low EW, water insoluble electrolyte materials includes providing a perfluorinated polymer resin that includes perfluorinated carbon-carbon backbone chain and sulfonyl fluoride ended perfluorinated side chains, extending from the perfluorinated backbone chains via an ether linkage, exposing the perfluorinated polymer resin to ammonia gas to convert the sulfonyl fluoride groups to sulfonamide groups, —SO2—NH2, which reacts with sulfonyl fluoride containing chemical agent(s) to form sulfonimide groups, and at the same time, generates low EW, 3-dimensional cross-linked, water-insoluble perfluorinated polymer electrolyte materials.

Abstract: A tetrafluoroethylene (TFE) copolymer film having a first endotherm between about 50° C. and about 300° C., a second endotherm between about 320° C. and about 350° C., and a third endotherm between about 350° C. and about 400° C. is provided. In exemplary embodiments, the third endotherm is approximately 380° C. In some embodiments, the second endotherm is between about 320° C. and about 330° C. or between about 330° C. and about 350° C. TFE copolymer films have a methane permeability less than about 20 ?g*micron/cm2/min. In addition, the dense articles have a void volume of less than about 20%. Methods for dense articles from core shell tetrafluoroethylene copolymers are also provided. The dense articles exhibit improved physical and mechanical properties such as adhesion and barrier properties.

Abstract: A proton exchange material includes perfluorinated carbon backbone chains and side chains extending off of the perfluorinated carbon backbone chains. The perfluorinated side chains include cross-link chains that have multiple sulfonimide groups, —SO2—NH—SO2—.