Provided is a polyvinylidene fluoride comprising: vinylidene fluoride unit; and a pentenoic acid unit represented by formula (1): CH.sub.2═CH— (CH).sub.2—COOY wherein Y represents at least one selected from the group consisting of an inorganic cation and an organic cation, a content of vinylidene fluoride unit is 95.0 to 99.99 mol % based on all monomer units of the polyvinylidene fluoride, and a content of the pentenoic acid unit is 0.01 to 5.0 mol % based on all monomer units of the polyvinylidene fluoride.

The present invention relates to a method for producing a polyacrylonitrile-based fiber, wherein the method polymerizes a monomer mixture including an acrylonitrile-based monomer, a carboxylic acid-based comonomer, and an acrylate-based comonomer, wherein the acrylate-based comonomer includes the steps of producing a polyacrylonitrile-based copolymer so as to be included in an amount of 4 to 20 parts by weight based on 100 parts by weight of the monomer mixture, fiberizing the polyacrylonitrile-based copolymer, oxidizing and stabilizing the fiberized polyacrylonitrile-based copolymer, which may control the oxidation stabilization reaction, particularly the cyclization reaction. Accordingly, the energy consumption of the oxidation stabilization reaction may be reduced, economical efficiency of the production of polyacrylonitrile-based fiber may be obtained, and the physical and mechanical properties of the carbon fiber may be improved.

The present invention relates to a method for producing a polyacrylonitrile-based fiber, wherein the method polymerizes a monomer mixture including an acrylonitrile-based monomer, a carboxylic acid-based comonomer, and an acrylate-based comonomer, wherein the acrylate-based comonomer includes the steps of producing a polyacrylonitrile-based copolymer so as to be included in an amount of 4 to 20 parts by weight based on 100 parts by weight of the monomer mixture, fiberizing the polyacrylonitrile-based copolymer, oxidizing and stabilizing the fiberized polyacrylonitrile-based copolymer, which may control the oxidation stabilization reaction, particularly the cyclization reaction. Accordingly, the energy consumption of the oxidation stabilization reaction may be reduced, economical efficiency of the production of polyacrylonitrile-based fiber may be obtained, and the physical and mechanical properties of the carbon fiber may be improved.

A method for preparing an olefin-olefinic alcohol copolymer and an olefin-olefinic alcohol copolymer prepared by the method are provided. The catalyst used in the method for preparing the olefin-olefinic alcohol copolymer has a diimine metal complex as shown in Formula I.

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A method for preparing an olefin-olefinic alcohol copolymer and an olefin-olefinic alcohol copolymer prepared by the method are provided. The catalyst used in the method for preparing the olefin-olefinic alcohol copolymer has a diimine metal complex as shown in Formula I.

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A curable composition for an electronic device, includes a curable material; and an oxide-containing complex; wherein the oxide-containing complex includes i) an oxide core and ii) an organic group chemically bound to an atom on a surface of the oxide core, the organic group includes a) a curable group reactable with the curable material and b) a linking group linking the atom on a surface of the oxide core to the curable group, and the oxide core includes an aluminum oxide, a silicon oxide, or a combination thereof.

A curable composition for an electronic device, includes a curable material; and an oxide-containing complex; wherein the oxide-containing complex includes i) an oxide core and ii) an organic group chemically bound to an atom on a surface of the oxide core, the organic group includes a) a curable group reactable with the curable material and b) a linking group linking the atom on a surface of the oxide core to the curable group, and the oxide core includes an aluminum oxide, a silicon oxide, or a combination thereof.

A biomagnetic microsphere and a preparation method and a method for protein isolation and purification therefor. The outer surface of a magnetic microsphere body of the biomagnetic microsphere has at least one liner polymer with a branched chain; one end of the linear polymer with a branched chain is covalently coupled to the outer surface of the magnetic microsphere body, and other parts are free on the outer surface of the magnetic microsphere body; a backbone of the linear polymer is a polyolefin backbone, and no cross-linking agent is required in the backbone forming process of the linear polymer. The prepared biomagnetic microsphere can implement efficient elution of target proteins and effectively reduce the retention time and retention ratio of the target proteins, and it is easy to operate and widely used.

A positive resist composition comprising a base polymer comprising recurring units (a) having the structure of an ammonium salt of N-carbonylsulfonamide having an iodized aromatic ring, and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group exhibits a high sensitivity, high resolution, low edge roughness and dimensional uniformity, and forms a pattern of good profile after exposure and development.

A positive resist composition comprising a base polymer comprising recurring units (a) having the structure of an ammonium salt of N-carbonylsulfonamide having an iodized aromatic ring, and recurring units (b1) having an acid labile group-substituted carboxyl group and/or recurring units (b2) having an acid labile group-substituted phenolic hydroxyl group exhibits a high sensitivity, high resolution, low edge roughness and dimensional uniformity, and forms a pattern of good profile after exposure and development.