A process for reducing the amount of soluble polymeric fractions in a sulfonyl fluoride polymer. The process comprises contacting the sulfonyl fluoride polymer with a fluorinated fluid followed by separation of the polymer from the fluid. The fluorinated fluid is selected from hydrofluoroethers and hydrofluoropolyethers. The invention further relates to sulfonyl fluoride polymers obtainable by the process and having a heat of fusion not exceeding 4 J/g and containing less than 15% by weight of polymeric fractions having an average content of monomeric units comprising a sulfonyl functional group exceeding 24 mole %. The sulfonyl fluoride polymers so obtained are particularly suitable for the preparation of ionomeric membranes for use in electrochemical devices.

A surface-treating agent for vulcanized rubber, comprising, based on 100 parts by weight, as solid matters, of isocyanate group-containing 1,2-polybutadiene, an organic solvent solution containing 10 to 160 parts by weight of fluororesin particles and 2.5 to 20 parts by weight of a perfluoroalkyl group-containing oligomer-based, fluorine-containing surfactant as a dispersant. The surface-treating agent for vulcanized rubber improves the solution stability of the organic solvent solution, improves the further hardness of the entire coating film formed from the surface-treating agent, abrasion resistance, and product torque evaluation, and is effectively used as, for example, a coating agent for seal lip parts of oil seals.

A surface-treating agent for vulcanized rubber, comprising, based on 100 parts by weight, as solid matters, of isocyanate group-containing 1,2-polybutadiene, an organic solvent solution containing 10 to 160 parts by weight of fluororesin particles and 2.5 to 20 parts by weight of a perfluoroalkyl group-containing oligomer-based, fluorine-containing surfactant as a dispersant. The surface-treating agent for vulcanized rubber improves the solution stability of the organic solvent solution, improves the further hardness of the entire coating film formed from the surface-treating agent, abrasion resistance, and product torque evaluation, and is effectively used as, for example, a coating agent for seal lip parts of oil seals.

To provide a membrane/electrode assembly excellent in the power generation characteristics in a wide temperature range and a wide humidity range; an electrolyte material suitable for a catalyst layer of the membrane/electrode assembly; and a liquid composition suitable for forming a catalyst layer of the membrane/electrode assembly.

To use an electrolyte material which is formed of a polymer (H) obtained by converting precursor groups in a polymer (F) having structural units (A) based on a perfluoromonomer having a precursor group represented by the formula (g1), structural units (B) represented by the formula (u2), and structural units (C) based on tetrafluoroethylene, wherein the proportion of the structural units (A) is from 8 to 19 mol %, the proportion of the structural units (B) is from 65 to 80 mol %, and the proportion of the structural units (C) is from 1 to 27 mol %, to ion exchange groups.

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A method of patterning a device includes forming a fluorinated photopolymer layer over a device substrate. The photopolymer layer has a lower portion proximate the device substrate and an upper portion distal the device substrate. The fluorinated photopolymer layer includes a radiation-absorbing dye and a fluorinated photopolymer having a solubility-altering reactive group. The photopolymer layer is exposed to patterned radiation to form exposed and unexposed areas in accordance with the patterned radiation and a developed structure is formed by removing unexposed areas using a developing agent that includes a first fluorinated solvent. The lower portion of the exposed area of the photopolymer layer has a dissolution rate in the developing agent that is at least 5 times higher than a dissolution rate for the upper portion.

A method of patterning a device includes forming a fluorinated photopolymer layer over a device substrate. The photopolymer layer has a lower portion proximate the device substrate and an upper portion distal the device substrate. The fluorinated photopolymer layer includes a radiation-absorbing dye and a fluorinated photopolymer having a solubility-altering reactive group. The photopolymer layer is exposed to patterned radiation to form exposed and unexposed areas in accordance with the patterned radiation and a developed structure is formed by removing unexposed areas using a developing agent that includes a first fluorinated solvent. The lower portion of the exposed area of the photopolymer layer has a dissolution rate in the developing agent that is at least 5 times higher than a dissolution rate for the upper portion.

A dispersion stabilizer for suspension polymerization of vinyl compounds comprising a vinyl alcohol polymer (A) which has a saponification degree of 30 mol % or more and less than 60 mol % and a viscosity-average polymerization degree (P) of more than 200 and less than 600, and has a terminal alkyl group having 6 to 18 carbon atoms, and in which a content of monomer units having an oxyalkylene group is 0.3 mol % or less and the relationship between the viscosity-average polymerization degree (P) and a modification rate (S) (mol %) of the alkyl group satisfies Formula (1). Thus, there can be provided a dispersion stabilizer for suspension polymerization with which, during suspension polymerization of vinyl compounds including vinyl chloride, even when it is used in a small amount, the absorbency of a plasticizer is high, resulting in easy processing and formation of coarse particles is little and the remaining monomer components can be easily removed.
50≦S×P/1.880<100  (1)

A dispersion stabilizer for suspension polymerization of vinyl compounds comprising a vinyl alcohol polymer (A) which has a saponification degree of 30 mol % or more and less than 60 mol % and a viscosity-average polymerization degree (P) of more than 200 and less than 600, and has a terminal alkyl group having 6 to 18 carbon atoms, and in which a content of monomer units having an oxyalkylene group is 0.3 mol % or less and the relationship between the viscosity-average polymerization degree (P) and a modification rate (S) (mol %) of the alkyl group satisfies Formula (1). Thus, there can be provided a dispersion stabilizer for suspension polymerization with which, during suspension polymerization of vinyl compounds including vinyl chloride, even when it is used in a small amount, the absorbency of a plasticizer is high, resulting in easy processing and formation of coarse particles is little and the remaining monomer components can be easily removed.
50≦S×P/1.880<100  (1)

To provide a water/oil repellent composition whereby it is possible to obtain an article which is excellent in each of water repellency, oil repellency and heavy rain durability, a method for its production, and an article which is excellent in each of water repellency, oil repellency, heavy rain durability and texture. The water/oil repellent composition comprises a copolymer containing structural units based on a monomer (a), structural units based on a monomer (b) and structural units based on a monomer (c). Here, the monomer (a) is a compound represented by (Z—Y).sub.nX (wherein Z is a C.sub.1-6 perfluoroalkyl group, etc.; Y is a bivalent organic group, etc.; n is 1 or 2; and X is a polymerizable unsaturated group). The monomer (b) is a (meth)acrylate having no polyfluoroalkyl group and having an alkyl group with at least 12 carbon atoms. The monomer (c) is a monomer having a poly(oxypolyfluoroalkylene) chain.

A method of preparing a fluoroelastomer capable of being vulcanized by using peroxide, the method comprising: in the presence of an initiator and a chain transfer agent, conducting emulsion polymerization reaction on comonomers to obtain a fluoroelastomer. The preparation method utilizes alkyl iodide RI.sub.x as the chain transfer agent, and introduces the atom I into the molecular structure of the polymer during the reaction, the atom I acting as a crosslinking point during peroxide vulcanization. The fluoroelastomer obtained via the preparation method greatly improves the performance after being vulcanized; in addition, due to the low cost and extensive sources of alkyl iodide, the preparation method also simplifies the manufacturing process, reduces cost, and has wide application prospects.