Provided is an aqueous binder composition for a secondary battery electrode, comprising a copolymer and a dispersion medium, wherein the copolymer comprises a structural unit (a) derived from a carboxylic acid group-containing monomer, a structural unit (b) derived from an amide group-containing monomer, a structural unit (c) derived from a nitrile group-containing monomer, and at least one anionic reactive emulsifier, with an improved binding capability. In addition, battery cells comprising the cathode prepared using the binder composition disclosed herein exhibits exceptional electrochemical performance.

A method of preparing an acrylonitrile-based copolymer for a carbon fiber. The method includes: preparing a reaction solution including a (meth)acrylonitrile-based monomer and a first reaction solvent; adding a first portion of a radical polymerization initiator to the reaction solution to initiate polymerization; and adding a second portion of the radical polymerization initiator to the reaction solution when a polymerization conversion ratio is between 70 to 80%.

A method of preparing an acrylonitrile-based copolymer for a carbon fiber. The method includes: preparing a reaction solution including a (meth)acrylonitrile-based monomer and a first reaction solvent; adding a first portion of a radical polymerization initiator to the reaction solution to initiate polymerization; and adding a second portion of the radical polymerization initiator to the reaction solution when a polymerization conversion ratio is between 70 to 80%.

Proposed is a method for producing an aqueous solution, which has a thickening property, of an N-vinyl carboxylic acid amide copolymer. This method for producing an aqueous solution of an N-vinyl carboxylic acid amide copolymer is characterized in that a liquid containing at least a non-hydrophilic monomer (B), which is at least one selected from acrylonitrile and methyl acrylate, and a liquid containing at least a polymerization initiator (D) are added dropwise to an aqueous solution of an N-vinyl carboxylic acid amide monomer (A), and polymerization is performed.

Proposed is a method for producing an aqueous solution, which has a thickening property, of an N-vinyl carboxylic acid amide copolymer. This method for producing an aqueous solution of an N-vinyl carboxylic acid amide copolymer is characterized in that a liquid containing at least a non-hydrophilic monomer (B), which is at least one selected from acrylonitrile and methyl acrylate, and a liquid containing at least a polymerization initiator (D) are added dropwise to an aqueous solution of an N-vinyl carboxylic acid amide monomer (A), and polymerization is performed.

The present application provides a trypsin detection film, a preparation method therefor, application thereof and a trypsin detection kit, which relates to the technical field of trypsin detection. The preparation method for the trypsin detection film comprises the following steps: providing a polymer film substrate; immersing the polymer film substrate in a dye solution to attach a dye to the polymer film substrate, so as to obtain a trypsin detection film.

The present application provides a trypsin detection film, a preparation method therefor, application thereof and a trypsin detection kit, which relates to the technical field of trypsin detection. The preparation method for the trypsin detection film comprises the following steps: providing a polymer film substrate; immersing the polymer film substrate in a dye solution to attach a dye to the polymer film substrate, so as to obtain a trypsin detection film.

An optimized process for the preparation of a spinning solution for the production of acrylic fiber precursors (PAN) of carbon fibers and an optimized process for the production of carbon fibers from said acrylic precursor (PAN), are described.

The present invention provides a thermally expandable microcapsule having excellent heat resistance and high expansion ratio and enabling production of a light, high-hardness molded article having excellent physical properties (abrasion resistance), and a composition for foam molding containing the thermally expandable microcapsule. Provided is a thermally expandable microcapsule including: a shell containing a polymer; and a volatile expansion agent as a core agent encapsulated by the shell, the shell containing silicon dioxide and a polymer obtained by polymerizing a monomer composition containing a carbonyl group-containing monomer, the thermally expandable microcapsule having a ratio of a peak intensity based on a C═O bond in the shell to a peak intensity based on the silicon dioxide in the shell (peak intensity based on C═O bond/peak intensity based on silicon dioxide) of 0.25 to 1.0 as determined by IR spectral analysis, the thermally expandable microcapsule having a maximum foaming temperature (Tmax) of 180° C. to 225° C.

The present invention provides a thermally expandable microcapsule having excellent heat resistance and high expansion ratio and enabling production of a light, high-hardness molded article having excellent physical properties (abrasion resistance), and a composition for foam molding containing the thermally expandable microcapsule. Provided is a thermally expandable microcapsule including: a shell containing a polymer; and a volatile expansion agent as a core agent encapsulated by the shell, the shell containing silicon dioxide and a polymer obtained by polymerizing a monomer composition containing a carbonyl group-containing monomer, the thermally expandable microcapsule having a ratio of a peak intensity based on a C═O bond in the shell to a peak intensity based on the silicon dioxide in the shell (peak intensity based on C═O bond/peak intensity based on silicon dioxide) of 0.25 to 1.0 as determined by IR spectral analysis, the thermally expandable microcapsule having a maximum foaming temperature (Tmax) of 180° C. to 225° C.