Provided is a dip-molded article, and more particularly, provided are a dip-molded article including: a layer derived from a latex composition for dip-molding; and a layer derived from a polymer including a repeating unit derived from a diacetylene-based compound, a latex composition for dip-molding, and a preparation method thereof.

Provided is a dip-molded article, and more particularly, provided are a dip-molded article including: a layer derived from a latex composition for dip-molding; and a layer derived from a polymer including a repeating unit derived from a diacetylene-based compound, a latex composition for dip-molding, and a preparation method thereof.

Provided is a latex composition for dip molding. The latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex and a hydrophobically modified alkali-soluble emulsion thickener, wherein the hydrophobically modified alkali-soluble emulsion thickener includes a copolymer including an associative portion and a non-associative portion, and the associative portion includes a monomer-derived repeating unit substituted by one or more first hydrophobic groups selected from the group consisting of alkyl, alkenyl, perfluoroalkyl, and carbosilyl having 8 to 15 carbon atoms, and aryl, arylalkyl, arylalkenyl, alicyclic alkyl, and polycyclic alkyl having 6 to 15 carbon atoms. A method of preparing the latex composition for dip molding, and a molded article manufactured therefrom are also provided.

Provided is a latex composition for dip molding. The latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex and a hydrophobically modified alkali-soluble emulsion thickener, wherein the hydrophobically modified alkali-soluble emulsion thickener includes a copolymer including an associative portion and a non-associative portion, and the associative portion includes a monomer-derived repeating unit substituted by one or more first hydrophobic groups selected from the group consisting of alkyl, alkenyl, perfluoroalkyl, and carbosilyl having 8 to 15 carbon atoms, and aryl, arylalkyl, arylalkenyl, alicyclic alkyl, and polycyclic alkyl having 6 to 15 carbon atoms. A method of preparing the latex composition for dip molding, and a molded article manufactured therefrom are also provided.

A latex composition includes a latex of a conjugated diene polymer (A) having a glass transition temperature of 10° C. or less and a latex of a polymer (B) having a glass transition temperature of more than 10° C., wherein the value of (CS(B)−CS(A)) is more than 0% by weight, where a chemical stability of the latex of the conjugated diene polymer (A) to CaCl.sub.2, when the solids concentration of the latex is 20% by weight, is defined as CS(A) (% by weight), and a chemical stability of the latex of the polymer (B) to CaCl.sub.2, when the solids concentration of the latex is 20% by weight, is defined as CS(B) (% by weight).

A latex composition includes a latex of a conjugated diene polymer (A) having a glass transition temperature of 10° C. or less and a latex of a polymer (B) having a glass transition temperature of more than 10° C., wherein the value of (CS(B)−CS(A)) is more than 0% by weight, where a chemical stability of the latex of the conjugated diene polymer (A) to CaCl.sub.2, when the solids concentration of the latex is 20% by weight, is defined as CS(A) (% by weight), and a chemical stability of the latex of the polymer (B) to CaCl.sub.2, when the solids concentration of the latex is 20% by weight, is defined as CS(B) (% by weight).

A method for producing a nitrile rubber, includes recovering a nitrile rubber from a latex of nitrile rubber by continuously feeding the latex of nitrile rubber and a coagulant into an extruder including a screw disposed inside a barrel to be rotatably driven, wherein the latex of nitrile rubber fed into the extruder contains 0.1 to 3 parts by weight of a hindered phenol-based antiaging agent having a molecular weight of 300 to 3000 relative to 100 parts by weight of the nitrile rubber.

A method for producing a nitrile rubber, includes recovering a nitrile rubber from a latex of nitrile rubber by continuously feeding the latex of nitrile rubber and a coagulant into an extruder including a screw disposed inside a barrel to be rotatably driven, wherein the latex of nitrile rubber fed into the extruder contains 0.1 to 3 parts by weight of a hindered phenol-based antiaging agent having a molecular weight of 300 to 3000 relative to 100 parts by weight of the nitrile rubber.

Disclosed is a dip-formed article comprising a layer derived from a latex composition for dip-forming, wherein the latex composition for dip-forming contains a carboxylic acid-modified nitrile-based copolymer latex, the carboxylic acid-modified nitrile-based copolymer latex contains a carboxylic acid-modified nitrile-based copolymer, and the dip-formed article has an elongation of more than 650% and satisfies the following Expressions 1 and 2,

[Expression 1]

k.sub.1′+k.sub.2′+k.sub.3′≤9.3 N/mm  (1)

[Expression 2]

0.55≤k.sub.1′/(k.sub.1′+k.sub.2′+k.sub.3′)  (2)

wherein k.sub.1′ is a value obtained by dividing an equilibrium coefficient k.sub.1 by a thickness of a test piece, and k.sub.2′ and k.sub.3′ are values obtained by dividing viscous coefficients k.sub.2 and k.sub.3 by the thickness of the test piece, respectively.

Disclosed is a dip-formed article comprising a layer derived from a latex composition for dip-forming, wherein the latex composition for dip-forming contains a carboxylic acid-modified nitrile-based copolymer latex, the carboxylic acid-modified nitrile-based copolymer latex contains a carboxylic acid-modified nitrile-based copolymer, and the dip-formed article has an elongation of more than 650% and satisfies the following Expressions 1 and 2,

[Expression 1]

k.sub.1′+k.sub.2′+k.sub.3′≤9.3 N/mm  (1)

[Expression 2]

0.55≤k.sub.1′/(k.sub.1′+k.sub.2′+k.sub.3′)  (2)

wherein k.sub.1′ is a value obtained by dividing an equilibrium coefficient k.sub.1 by a thickness of a test piece, and k.sub.2′ and k.sub.3′ are values obtained by dividing viscous coefficients k.sub.2 and k.sub.3 by the thickness of the test piece, respectively.