Method of preparing carboxylic acid-modified nitrile-based copolymer latex

Patent metadata

Field	Value
Publication number	US-11965080-B2
Application number	US-202017299571-A
Country	US
Kind code	B2
Filing date	Aug 12, 2020
Priority date	Oct 7, 2019
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

A method of preparing a carboxylic acid-modified nitrile-based copolymer latex is provided. The method of preparing a carboxylic acid-modified nitrile-based copolymer later includes emulsion-polymerizing a monomer mixture including a conjugated diene-based monomer, an ethylenically unsaturated nitrile-based monomer, and an ethylenically unsaturated acid monomer in the presence of a cross-linking agent including glyoxal.

First claim

The invention claimed is:

1. A method of preparing a carboxylic acid-modified nitrile-based copolymer latex, comprising emulsion-polymerizing a monomer mixture including a conjugated diene-based monomer, an ethylenically unsaturated nitrile-based monomer, and an ethylenically unsaturated acid monomer in the presence of a cross-linking agent including glyoxal.

2. The method of claim 1 , wherein the monomer mixture includes a water soluble monomer.

3. The method of claim 2 , wherein the emulsion polymerization is performed in the presence of a persulfate-based polymerization initiator including sodium persulfate, potassium persulfate, or ammonium persulfate; and an initial activator including hydroperoxide, ferrous sulfate, or sodium metabisulfite.

4. The method of claim 1 , wherein the conjugated diene-based monomer includes 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-ethyl-1,3-butadiene, 1,3-pentadiene, or isoprene.

5. The method of claim 1 , wherein the ethylenically unsaturated nitrile-based monomer includes acrylonitrile, methacrylonitrile, fumaronitrile, α-chloronitrile, or α-cyanoethylacrylonitrile.

6. The method of claim 1 , wherein the ethylenically unsaturated acid monomer includes acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, citraconic anhydride, styrenesulfonic acid, monobutyl fumarate, monobutyl maleate, or mono-2-hydroxypropyl maleate.

7. The method of claim 2 , wherein the water soluble monomer includes hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, dimethylaminoethyl acrylate, or diethylaminoethyl methacrylate.

8. The method of claim 3 , wherein a content of the persulfate-based polymerization initiator is 0.1 to 2 parts by weight with respect to a total of 100 parts by weight of the monomer mixture.

9. The method of claim 3 , wherein a content of the initial activator is 1 to 100 parts by weight with respect to a content of 100 parts by weight of the persulfate-based polymerization initiator.

10. The method of claim 1 , wherein a content of the cross-linking agent is 0.1 to 1 parts by weight with respect to a total of 100 parts by weight of the monomer mixture.

11. A carboxylic acid-modified nitrile-based copolymer latex comprising a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived repeating unit, an ethylenically unsaturated nitrile-based monomer-derived repeating unit, an ethylenically unsaturated acid monomer-derived repeating unit, and a glyoxal-derived part.

12. A carboxylic acid-modified nitrile-based copolymer latex comprising a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived repeating unit, an ethylenically unsaturated nitrile-based monomer-derived repeating unit, an ethylenically unsaturated acid monomer-derived repeating unit, a water soluble monomer-derived repeating unit, and a glyoxal-derived part,
wherein a pKa is 8.5 to 9.5.

13. A latex composition for dip molding comprising the carboxylic acid-modified nitrile-based copolymer latex of claim 11 .

14. A dip-molded article comprising a layer derived from the latex composition for dip molding of claim 13 .

Assignees

• Lg Chemical Ltd

Inventors

• Kim Jung Eun
• Kim Ji Hyun
• Kwon Won Sang
• Jang Myung Su
• Oh Seung Whan

Classifications

• C08L13/02 Primary

  Latex · CPC title

• B29C41/003

  characterised by the choice of material · CPC title

• B29C41/14

  Dipping a core {(B29C41/10 takes precedence)} · CPC title

• B29C41/46

  Heating or cooling · CPC title

• C08J5/02 Primary

  Direct processing of dispersions, e.g. latex, to articles · CPC title