Abstract:
Described herein is a process for recovering a branched, ether-containing fluorinated emulsifier from an anion exchange resin by (1) contacting the anion exchange resin with a recovery fluid to form an eluate, the recovery fluid comprising an ammonium salt, water, and a water-miscible solvent, wherein the fluorinated emulsifier is of the formula: [Rf-(0-R′f)n-0-CF(CF3)-C(0)0-]i M+1; and (2) separating the anion exchange resin from the eluate.
Abstract translation:本文描述的是通过(1)使阴离子交换树脂与回收流体接触以形成洗脱液,从阴离子交换树脂中回收支链含醚的含氟乳化剂的方法,该回收流体包含铵盐,水和 其中氟化乳化剂具有下式:[Rf-(0-R'f)n-0-CF(CF 3)-C(O)O-] i M + 1; 和(2)从洗脱液中分离阴离子交换树脂。
Abstract:
The copolymer includes divalent units represented by formula —[CF2—CF2]—, at least one divalent unit represented by formula (I): and at least one divalent unit independently represented by formula (II): A is —N(RFa)2 or a is non-aromatic, 5- to 8-membered, perfluorinated ring comprising one or two nitrogen atoms in the ring and optionally comprising at least one oxygen atom in the ring, each RFa is independently linear or branched perfluoroalkyl having 1 to 8 carbon atoms and optionally interrupted by at least one catenated O or N atom, each Y is independently —H or —F, with the proviso that one Y may be —CF3, h is 0, 1, or 2, each i is independently 2 to 8, and j is 0, 1, or 2. A catalyst ink and polymer electrolyte membrane including the copolymer are also provided.
Abstract:
A composite includes a fluorinated polymer and nanoparticles of a metal salt. The metal salt has a solubility product of not more than 1×10−4. The fluorinated polymer includes a fluorinated polymer backbone chain and a plurality of groups represented by formula —SO2X, in which each X is independently —NZH, —NZSO2(CF2)1-6SO2X′, —NZ[SO2(CF2)dSO2NZ]1-10SO2(CF2)dSO2X′ or —OZ, and Z is independently a hydrogen, an alkali-metal cation, or a quaternary ammonium cation, X′ is independently —NZH or —OZ, and each d is independently 1 to 6. A polymer electrolyte membrane, an electrode, and a membrane electrode assembly including the composite are also provided.
Abstract:
The copolymer includes divalent units represented by formula —[CF2—CF2]—, divalent units represented by formula: and one or more divalent units independently represented by formula: The copolymer has an —SO2X equivalent weight in a range from 300 to 2000. A polymer electrolyte membrane that includes the copolymer and a membrane electrode assembly that includes such a polymer electrolyte membrane are also provided.
Abstract:
The invention relates to a curable dental composition comprising a cationically hardenable compound (A) comprising at least two aziridine moieties, a starter (B) being suitable to cure the hardenable compound (A), polymeric particles as filler component (C), the polymeric particles having a maximum particle size of 150 μm or below and the component(s) the polymeric particles are made of being based on fluoropolymers comprising more than 99% monomer repeating units of tetra fluoro ethylene. The invention also relates to the use of such composition for producing a dental impression material or a dental retraction material.
Abstract:
The copolymer includes divalent units represented by formula: (I), one or more independently selected fluorinated divalent units, and —SO2X end groups. In this formula, b is 2 to 8, c is 0 to 2, and e is 1 to 8. In each SO2X, X is independently F, —NZH, —NZSO2(CF2)1−6SO2X′, —NZ[SO2(CF2)aSO2NZ]1−10SO2X′, or —OZ, wherein Z is a hydrogen, an alkali-metal cation or a quaternary ammonium cation, X′ is independently —NZH or —OZ, and each a is independently 1 to 6. The copolymer has an —SO2X equivalent weight of up to 1000. The method includes copolymerizing components including fluorinated olefin and a compound represented by formula CF2═CF—CF2(O—CbF2b)c—O—(CeF2e)—SO2X′, wherein b, c, and e are as defined above. A method of making a membrane using the copolymer or ionomer is also provided. A polymer electrolyte membrane that includes the copolymer or the ionomer and a membrane electrode assembly that includes such a polymer electrolyte membrane are also provided.
Abstract:
Described herein is a process for recovering a branched, ether-containing fluorinated emulsifier from an anion exchange resin by (1) contacting the anion exchange resin with a recovery fluid to form an eluate, the recovery fluid comprising an ammonium salt, water, and a water-miscible solvent, wherein the fluorinated emulsifier is of the formula: [Rf-(0-R′f)n-0-CF(CF3)-C(0)0-]i M+1; and (2) separating the anion exchange resin from the eluate.
Abstract:
Provided are processes for upconcentrating fluoropolymer dispersions. Also provided are upconcentrated dispersions and substrates coated with such dispersions.
Abstract:
The process produces a fluorinated olefin from a fluorinated copolymer having at least one of sulfonic acid groups, carboxylic acid groups, or salts thereof. The process includes heating the fluorinated copolymer at a first temperature not more than 450° C. to decompose at least one of the sulfonic acid groups, carboxylic acid groups, or salts thereof to form a partially pyrolyzed intermediate and subsequently heating the partially pyrolyzed intermediate at a second temperature of at least 550° C. to produce the fluorinated olefin.
Abstract:
Fluorinated ionomers (i.e., ion conducting polymers) that include a fluorinated polymer backbone with covalently bound pendent groups that include heteropolyacid (HP A) groups, or salts thereof, and perfluorosulfonic acid (PF SA) groups, or salts thereof, as well as polymer electrolyte membranes, fuel cells, and methods.