Method of preparing graft polymer

Patent metadata

Field	Value
Publication number	US-12091483-B2
Application number	US-202017436520-A
Country	US
Kind code	B2
Filing date	Sep 7, 2020
Priority date	Sep 24, 2019
Publication date	Sep 17, 2024
Grant date	Sep 17, 2024

Abstract

Provided is a method of preparing a graft polymer, which includes: polymerizing a monomer mixture comprising a carboxylic acid monomer and methyl acrylate, wherein the carboxylic acid monomer is included at 1.5 to 2.5 wt %, and thus preparing an acrylic coagulant having an average particle diameter of 60 to 70 nm; polymerizing diene-based monomers in the presence of an emulsifier containing a salt of a compound and thus preparing a first diene-based rubber polymer; enlarging the first diene-based rubber polymer using the acrylic coagulant and thus preparing a second diene-based rubber polymer; and graft-polymerizing an aromatic vinyl-based monomer and a vinyl cyanide-based monomer to the second diene-based rubber polymer and thus preparing a graft polymer.

First claim

The invention claimed is:

1. A method of preparing a graft polymer, comprising:
polymerizing a monomer mixture comprising a carboxylic acid monomer and methyl acrylate, wherein the carboxylic acid monomer is included at 1.5 to 2.5 wt %, and thus preparing an acrylic coagulant having an average particle diameter of 60 to 70 nm;
polymerizing diene-based monomers in the presence of an emulsifier containing a salt of a compound represented by Chemical Formula 1 and thus preparing a first diene-based rubber polymer;
enlarging the first diene-based rubber polymer using the acrylic coagulant and thus preparing a second diene-based rubber polymer; and
graft-polymerizing an aromatic vinyl-based monomer and a vinyl cyanide-based monomer to the second diene-based rubber polymer and thus preparing a graft polymer,

wherein, in Chemical Formula 1,
X is a C 1 -C 20 tetravalent or higher aliphatic hydrocarbon,
R 1 to R 4 , which are the same or different from each other, are each independently hydrogen, a C 1 -C 20 monovalent aliphatic hydrocarbon, or -L 3 -COOH,
L 1 to L 3 , which are the same or different from each other, are each independently a direct bond or a C 1 -C 20 divalent aliphatic hydrocarbon, and
l and m, which are the same or different from each other, are each independently 0 to 6.

2. The method of claim 1 , wherein an amount of the acrylic coagulant is 1 part by weight to 3 parts by weight based on 100 parts by weight of the first diene-based rubber polymer.

3. The method of claim 1 , wherein the emulsifier is present in an amount of 0.5 parts by weight to 1.5 parts by weight based on 100 parts by weight of the diene-based monomers.

4. The method of claim 1 , wherein the emulsifier contains a salt of one or more selected from the group consisting of compounds represented by the following Chemical Formula 2 to Chemical Formula 4:

wherein, in Chemical Formula 2 to Chemical Formula 4,
L 4 to L 10 , which are the same or different from each other, are each independently a direct bond, a C 1 -C 15 linear alkylene group, or a C 2 -C 15 linear alkenylene group, provided that L 5 is not a direct bond, and
R 5 to R 10 , which are the same or different from each other, are each independently a C 1 -C 15 linear alkyl group or a C 2 -C 15 linear alkenyl group.

5. The method of claim 1 , wherein the emulsifier contains a salt of one or more selected from the group consisting of compounds represented by the following Chemical Formula 5 to Chemical Formula 10:

6. The method of claim 1 , wherein the salt of the compound represented by Chemical Formula 1 is an alkali metal salt of the compound represented by Chemical Formula 1.

7. The method of claim 1 , wherein the carboxylic acid monomer is one or more selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, and maleic acid.

8. The method of claim 1 , wherein the first diene-based rubber polymer has an average particle diameter of 90 nm to 150 nm.

9. The method of claim 1 , wherein the second diene-based rubber polymer has an average particle diameter of 250 nm to 400 nm.

Assignees

• Lg Chemical Ltd

Inventors

• Kim Hyung Joon
• Kim Geon Soo
• Hwang Moon Ja
• Jeon Hee Jung
• Kim Chang Hoe
• Chae Min Su

Classifications

• C08F6/18

  Increasing the size of the dispersed particles · CPC title

• C08F2/24

  with the aid of emulsifying agents · CPC title

• C08F220/04

  Acids; Metal salts or ammonium salts thereof · CPC title

• C08F220/18

  with acrylic or methacrylic acids · CPC title

• C08F2/26

  anionic · CPC title