摘要:
Core/shell polymer is provided wherein the core comprises non-melt flowable PTFE and the shell comprises melt-fabricable perfluoropolymer, the core/shell polymer providing a thixotropic melt blend and improved physical properties as compared to the melt-fabricable perfluoropolymer by itself.
摘要:
Disclosed is an aqueous polymerization process for the manufacture of a fluoropolymer comprising repeating units arising from a perfluoromonomer and a monomer having a functional group and a polymerizable carbon-carbon double bond, comprising: (A) combining water and a perfluoromonomer to form a reaction mixture; (B) initiating polymerization of the perfluoromonomer; (C) polymerizing a portion of the perfluoromonomer to form particles of polymerized perfluoromonomer in the reaction mixture; (D) adding to the reaction mixture a monomer having a functional group and a polymerizable carbon-carbon double bond; and (E) polymerizing the perfluoromonomer and the monomer having a functional group and a polymerizable carbon-carbon double bond in the presence of the particles of polymerized perfluoromonomer to form the fluoropolymer. The fluoropolymer is useful as an adhesive and coating.
摘要:
Disclosed is a melt processible semicrystalline fluoropolymer comprising: (a) about 2 to about 20 weight percent of repeating units arising from hexafluoropropylene; (b) about 0.001 to about 1 weight percent of repeating units arising from a hydrocarbon monomer having a carboxyl group and a polymerizable carbon-carbon double bond; and (c) the remaining weight percent of repeating units arising from tetrafluoroethylene. This melt processible semicrystalline fluoropolymer is impermeable to fuels and is useful as a lining for petroleum fuel tubing, as well as chemical resistance coating for, or adhesive between, perfluoropolymer and other polymers, metals and inorganics.
摘要:
Tensile strength after heat aged of articles molded from melt-fabricable perfluoropolymer is improved by incorporating polytetrafluoroethylene as dispersed submicrometer-size particles into the melt-fabricable perfluoropolymer.
摘要:
Copolymers of tetrafluoroethylene and perfluoro(ethyl vinyl ether) having perfluoro(ethyl vinyl ether) content of at least 3 wt % exhibit excellent toughness even at melt viscosities of no greater than 25.times.10.sup.3 Pa.s. The copolymers can advantageously be made by aqueous dispersion copolymerization of the monomers in the absence of alkaline buffer and preferably in the absence of organic solvent.
摘要:
A cathode catalyst layer used for a polymer electrolyte fuel cell that includes an electrolyte membrane is provided. The cathode catalyst layer comprises a catalyst having weight of not greater than 0.3 mg/cm2 of a reaction surface of the cathode catalyst layer that is adjoining the electrolyte membrane; and an electrolyte resin having oxygen permeability of not less than 2.2*10−14 mol/m/s/Pa in an environment of temperature of 80 degrees Celsius and relative humidity of 50%.
摘要翻译:提供了用于包含电解质膜的固体高分子型燃料电池的阴极催化剂层。 阴极催化剂层包含负极与电解质膜相邻的阴极催化剂层的反应面重量不大于0.3mg / cm 2的催化剂; 以及在80℃的温度和50%的相对湿度的环境中具有不低于2.2×10-14mol / m / s / Pa的透氧度的电解质树脂。
摘要:
This invention relates to solid polymer electrolyte materials for use in one or more electrode of a fuel cell. The solid polymer electrolyte materials comprise one or more ionomer which comprises polymerized units of monomers A and monomers B, wherein monomers A are perfluoro dioxole or perfluoro dioxolane monomers, and the monomers B are functionalized perfluoro olefins having fluoroalkyl sulfonyl, fluoroalkyl sulfonate or fluoroalkyl sulfonic acid pendant groups, CF2═CF(O)[CF2]nSO2X.
摘要翻译:本发明涉及用于燃料电池的一个或多个电极的固体聚合物电解质材料。 固体聚合物电解质材料包含一种或多种离聚物,其包含单体A和单体B的聚合单元,其中单体A是全氟二氧杂环戊烯单体或全氟二氧戊环单体,单体B是具有氟代烷基磺酰基,氟烷基磺酸酯或氟烷基磺酸的全氟烯烃的官能化 侧链基团,CF 2 = CF(O)[CF 2] n SO 2 X。
摘要:
Disclosed is a melt processible semicrystalline fluoropolymer comprising: (a) about 0.001 to about 25 weight percent of repeating units arising from a hydrocarbon monomer having a functional group and a polymerizable carbon-carbon double bond, wherein said functional group is at least one selected from the group consisting of amine, amide, hydroxyl, phosphonate, sulfonate, nitrile, boronate and epoxidehydrocarbon monomer; and (b) the remaining weight percent of repeating units arising from tetrafluoroethylene. This melt processible semicrystalline fluoropolymer is impermeable to fuels and is useful as a lining for petroleum fuel tubing, as well as chemical resistance coating for, or adhesive between, perfluoropolymer and other polymers, metals and inorganics.
摘要:
A melt-mixed composition of non-melt flowable polytetrafluoroethylene (PTFE) and melt-fabricable perfluoropolymer is provided that exhibits thixotropy at increasing shear rate in the molten state and high elongation at break even at PTFE concentrations well above 4 wt %, based on the combined weight of the PTFE and the perfluoropolymer, e.g. at least 200% up to at least 30 wt % PTFE, the composition also exhibiting the structure of a dispersion of submicrometer-size particles of the PTFE in a continuous phase of the melt-fabricable perfluoropolymer.
摘要:
Aqueous dispersions on non-melt flowable PTFE and melt-fabricable perfluoropolymer are mixed together, followed by recovery of the resultant mixture of the dispersed particles of each of these polymers, and melt mixing of the resultant mixture of particles to obtain a blend in which the PTFE particles form the disperse phase and the perfluoropolymer forms the continuous phase, the melt mixing producing advantageous melt viscosities and the blend exhibiting advantageous physical properties even at high PTFE contents of about 30 wt %.