	US 12,441,826 B2
	Method of preparing vinyl cyanide compound-conjugated diene rubber-aromatic vinyl compound graft copolymer, method of preparing thermoplastic resin composition including the same, and thermoplastic resin composition including the same
Young Hwan Jeong, Daejeon (KR); Jaemin Suk, Daejeon (KR); and Young Min Kim, Daejeon (KR)
Assigned to LG CHEM, LTD., Seoul (KR)
Appl. No. 17/642,071
Filed by LG CHEM, LTD., Seoul (KR)
PCT Filed Aug. 19, 2021, PCT No. PCT/KR2021/010997 § 371(c)(1), (2) Date Mar. 10, 2022, PCT Pub. No. WO2022/075578, PCT Pub. Date Apr. 14, 2022.
Claims priority of application No. 10-2020-0130030 (KR), filed on Oct. 8, 2020; application No. 10-2020-0130031 (KR), filed on Oct. 8, 2020; and application No. 10-2021-0100526 (KR), filed on Jul. 30, 2021.
Prior Publication US 2022/0411558 A1, Dec. 29, 2022
Int. Cl. C08L 25/12 (2006.01); C08F 279/04 (2006.01)

CPC C08F 279/04 (2013.01) [C08L 25/12 (2013.01)]

9 Claims

1. A method of preparing a vinyl cyanide compound-conjugated diene rubber-aromatic vinyl compound graft copolymer, comprising:

step (a) comprising adding 0.1 to 2 parts by weight of an emulsifier, 0.1 to 0.4 parts by weight of an electrolyte, and a molecular weight regulator to 20 to 40 parts by weight of 100 parts by weight in total of a conjugated diene compound and performing polymerization;

step (b) comprising adding, after step (a), the remaining conjugated diene compound and a molecular weight regulator and performing polymerization to obtain conjugated diene rubber latex;

step (c) comprising preparing enlarged conjugated diene rubber latex by adding 0.3 to 1.1 parts by weight of an acid enlarging agent to 100 parts by weight of the conjugated diene rubber latex based on solids to enlarge the conjugated diene rubber latex; and

step (d) comprising graft-polymerizing 40 to 70% by weight of the enlarged conjugated diene rubber latex based on solids, 15 to 45% by weight of an aromatic vinyl compound, and 5 to 25% by weight of a vinyl cyanide compound to obtain a vinyl cyanide compound-conjugated diene rubber-aromatic vinyl compound graft copolymer,

wherein the enlarged conjugated diene rubber latex obtained in step (c) has an average particle diameter of 2,800 to 3,800 Å and a full width at half maximum of 1,400 to 2,700 Å in particle size distribution.