The present technology provides a carboxylic acid-modified nitrile-based copolymer latex including a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit, wherein a pKa is 9.5 to 10.2, and the carboxylic acid-modified nitrile-based copolymer latex satisfies General Formulas 1 and 2.

The present technology provides a carboxylic acid-modified nitrile-based copolymer latex including a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit, wherein a pKa is 9.5 to 10.2, and the carboxylic acid-modified nitrile-based copolymer latex satisfies General Formulas 1 and 2.

A latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex and a cholate-based emulsifier, wherein the cholate-based emulsifier is included in an amount of 0.02 to 3 parts by weight based on a solid content with respect to a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. A method of preparing the latex composition for dip molding and a molded article produced using the same are also provided.

A latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex and a cholate-based emulsifier, wherein the cholate-based emulsifier is included in an amount of 0.02 to 3 parts by weight based on a solid content with respect to a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. A method of preparing the latex composition for dip molding and a molded article produced using the same are also provided.

A method for producing a carboxyl group-containing nitrile rubber including the steps of: polymerizing a monomer mixture including an α,β-ethylenically unsaturated nitrile monomer and a carboxyl group-containing monomer in a solvent; terminating a polymerization reaction by adding a nitrous acid salt and a water-insoluble hydroquinone as polymerization terminators to the polymerization system, thereby obtaining a dispersion of the carboxyl group-containing nitrile rubber having a pH of 7 or below; and coagulating the dispersion of the carboxyl group-containing nitrile rubber, thereby obtaining the carboxyl group-containing nitrile rubber in the solid state, wherein the amount of the nitrous acid salt to be used is 0.15 parts by weight or less relative to 100 parts by weight of the monomer mixture used in the polymerization reaction.

Disclosed is a latex composition for dip molding including a carboxylic acid-modified nitrile-based copolymer latex satisfying General Formula 1, wherein the carboxylic acid-modified nitrile-based copolymer includes: 15 wt % to 30 wt % of the ethylenic unsaturated nitrile-based monomer-derived unit and 2.5 wt % to 4.5 wt % of the ethylenic unsaturated acid monomer-derived unit, and a molded article:

1.0 mm.sup.2/s≤CV.sub.0≤3.0 mm.sup.2/s.  General Formula 1

The present invention relates to methods for reprocessing elastomeric films or articles comprising an elastomer film wherein the elastomeric film is made from a polymer latex comprising: (a) particles of a carboxylated conjugated diene nitrile latex polymer (a) obtainable by free-radical emulsion polymerization of a mixture of ethylenically unsaturated monomers comprising: 15 to 99 wt.-% of conjugated dienes; 1 to 80 wt.-% of monomers selected from ethylenically unsaturated nitrile compounds; 0.05 to 10 wt.-% of ethylenically unsaturated carboxylic acids and/or salts thereof; 0 to 50 wt.-% of vinyl aromatic monomers; and 0 to 65 wt.-% of alkyl esters of ethylenically unsaturated acids, the weight percentages being based on the total monomers in the mixture in combination or association with (b) particles of a latex polymer (b) comprising at least one oxirane-functional group;
wherein the monomer composition of the latex polymer (a) is different from the monomer composition of the latex polymer (b) and to the use said polymer latex to make an elastomeric film obtained from said polymer latex self-healing, repairable and/or recyclable.

The present invention relates to methods for reprocessing elastomeric films or articles comprising an elastomer film wherein the elastomeric film is made from a polymer latex comprising: (a) particles of a carboxylated conjugated diene nitrile latex polymer (a) obtainable by free-radical emulsion polymerization of a mixture of ethylenically unsaturated monomers comprising: 15 to 99 wt.-% of conjugated dienes; 1 to 80 wt.-% of monomers selected from ethylenically unsaturated nitrile compounds; 0.05 to 10 wt.-% of ethylenically unsaturated carboxylic acids and/or salts thereof; 0 to 50 wt.-% of vinyl aromatic monomers; and 0 to 65 wt.-% of alkyl esters of ethylenically unsaturated acids, the weight percentages being based on the total monomers in the mixture in combination or association with (b) particles of a latex polymer (b) comprising at least one oxirane-functional group;
wherein the monomer composition of the latex polymer (a) is different from the monomer composition of the latex polymer (b) and to the use said polymer latex to make an elastomeric film obtained from said polymer latex self-healing, repairable and/or recyclable.

The present technology provides a carboxylic acid-modified nitrile-based copolymer latex including a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit, wherein the carboxylic acid-modified nitrile-based copolymer latex satisfies General Formula 1 and General Formula 2.

The present technology provides a carboxylic acid-modified nitrile-based copolymer latex including a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit, wherein the carboxylic acid-modified nitrile-based copolymer latex satisfies General Formula 1 and General Formula 2.