Acrylic copolymer coagulant and method of preparing graft copolymer using the same

Patent metadata

Field	Value
Publication number	US-12415877-B2
Application number	US-202017436025-A
Country	US
Kind code	B2
Filing date	Jul 15, 2020
Priority date	Jul 24, 2019
Publication date	Sep 16, 2025
Grant date	Sep 16, 2025

Abstract

The present invention provides an acrylic copolymer coagulant which is a copolymer of a monomer mixture comprising a carboxylic acid-based monomer and an acrylic monomer, and a method of preparing a graft copolymer using the same. According to the present invention, a graft copolymer excellent in impact strength, surface gloss characteristics, and processability can be prepared.

First claim

The invention claimed is:

1. An acrylic copolymer coagulant which is a copolymer of a monomer mixture comprising a carboxylic acid-based monomer and an acrylic monomer represented by Chemical Formula 1 below,
wherein a content X of a carboxylic acid-based monomer unit in the acrylic copolymer coagulant satisfies Expression 1 below, and
an average particle diameter Y of the acrylic copolymer coagulant satisfies Expression 2 below,
wherein the acrylic copolymer coagulant has a weight-average molecular weight of 700,000 g/mol to 950,000 g/mol:

in Chemical Formula 1,
n is 0,
2+( n+ 1) 2 −0.5( n+ 1)≤ X≤ 2+( n+ 1) 2 +0.5( n+ 1)  <Expression 1>

{20.817×( n+ 1) 2 −27.35×( n+ 1)+28.433}/ X× 10−1.5≤ Y≤{ 20.817×( n+ 1) 2 −27.35×( n+ 1)+28.433}/ X× 10+1.5  <Expression 2>

in Expressions 1 and 2,
n is an n value of Chemical Formula 1,
X is a content of a carboxylic acid-based monomer unit comprised in the acrylic copolymer coagulant (units: wt %), and
Y is an average particle diameter of the acrylic copolymer coagulant (units: nm).

2. The acrylic copolymer coagulant of claim 1 , wherein an average particle diameter Y of the acrylic copolymer coagulant is in a range of 61.5 nm to 89.1 nm.

3. An acrylic copolymer coagulant which is a copolymer of a monomer mixture comprising a carboxylic acid-based monomer and an acrylic monomer represented by Chemical Formula 1 below,
wherein a content X of a carboxylic acid-based monomer unit in the acrylic copolymer coagulant satisfies Expression 1 below, and
an average particle diameter Y of the acrylic copolymer coagulant satisfies Expression 2 below,
wherein the acrylic copolymer coagulant has a weight-average molecular weight of 250,000 g/mol to 350,000 g/mol:

in Chemical Formula 1,
n is 1,
2+( n+ 1)2−0.5( n+ 1)≤ X≤ 2+( n+ 1)2+0.5( n+ 1)  <Expression 1>

{20.817×( n+ 1)2−27.35×( n+ 1)+28.433}/ X× 10−1.5≤ Y≤{ 20.817×( n+ 1)2−27.35×( n+ 1)+28.433}/ X× 10+1.5  <Expression 2>

in Expressions 1 and 2,
n is an n value of Chemical Formula 1,
X is a content of a carboxylic acid-based monomer unit comprised in the acrylic copolymer coagulant (units: wt %), and
Y is an average particle diameter of the acrylic copolymer coagulant (units: nm).

4. The acrylic copolymer coagulant of claim 3 , wherein an average particle diameter Y of the acrylic copolymer coagulant is in a range of 80 nm to 115.5 nm.

5. A method of preparing a graft copolymer, comprising:
preparing a second diene-based rubber polymer by coagulation of a first diene-based rubber polymer with the acrylic copolymer coagulant according to claim 1 ; and
preparing a graft copolymer by graft polymerization of the second diene-based rubber polymer with an aromatic vinyl-based monomer and a vinyl cyanide-based monomer.

6. The method of claim 5 , wherein the first diene-based rubber polymer has an average particle diameter of 90 to 110 nm, and the second diene-based rubber polymer has an average particle diameter of 250 to 350 nm.

Assignees

• Lg Chemical Ltd

Inventors

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

Classifications

• C08L51/04

  grafted on to rubbers · CPC title

• C08C1/15

  characterised by the coagulants used · CPC title

• C08F279/04

  Vinyl aromatic monomers and nitriles as the only monomers · CPC title

• C08F220/06 Primary

  Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof · CPC title

• C08C1/065

  Increasing the size of dispersed rubber particles · CPC title