Method for preparing vinyl chloride copolymer and vinyl chloride copolymer produced by the same

Patent metadata

Field	Value
Publication number	US-10017594-B2
Application number	US-201615242192-A
Country	US
Kind code	B2
Filing date	Aug 19, 2016
Priority date	Jul 3, 2015
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

The present invention relates to a method for preparing a vinyl chloride copolymer having good heat resistance and a vinyl chloride copolymer produced by the same. In the preparation method, by not injecting an N-substituted maleimide based compound used as a comonomer together with a vinyl chloride monomer at one time in a pre-polymerization step, but in division in a specific ratio, a copolymer with a uniform distribution of the N-substituted maleimide based compound and the vinyl chloride monomer may be easily prepared, and the vinyl chloride copolymer may have good heat resistance. Accordingly, the preparation method of a vinyl chloride copolymer and the vinyl chloride copolymer according to the present invention may be easily applied to industries requiring the copolymer, particularly industries requiring a resin having good heat resistance as well as industries using a vinyl chloride resin.

First claim

The invention claimed is:

1. A method for preparing a vinyl chloride copolymer comprising:
pre-polymerizing for forming seed particles by polymerizing the vinyl chloride monomer and a first copolymerizable monomer; and
post-polymerizing for adding a second copolymerizable monomer to the seed particles and polymerizing,
wherein a total amount of the first copolymerizable monomer and the second copolymerizable monomer is from 5 to 30 parts by weight on the basis of 100 parts by weight of the vinyl chloride monomer,
wherein the first copolymerizable monomer and the second copolymerizable monomer are an N-substituted maleimide based monomer, and
wherein the first copolymerizable monomer and the second copolymerizable monomer are used in a weight ratio between 3:7 and 4:6.

2. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the second copolymerizable monomer is added at a time within ¼ of an entire post-polymerization process after initiating the post-polymerization.

3. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the first copolymerizable monomer and the second copolymerizable monomer are the same material.

4. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the N-substituted maleimide based monomer is at least one selected from the group consisting of N-methyl maleimide, N-ethyl maleimide, N-n-propyl maleimide, N-isopropyl maleimide, N-n-butyl maleimide, N-phenyl maleimide, N-hydroxyphenyl maleimide, N-carboxyphenyl maleimide, N-nitrophenyl maleimide, and N-methylphenyl maleimide.

5. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the N-substituted maleimide based monomer is N-phenyl maleimide.

6. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the pre-polymerization is performed by a bulk polymerization under a reaction pressure between 8.5 K/G and 13 K/G at a temperature between 30° C. and 70° C.

7. The method for preparing a vinyl chloride copolymer of claim 1 , wherein the post-polymerization is performed by a bulk polymerization under a reaction pressure between 7.5 K/G and 11 K/G at a temperature between 30° C. and 70° C.

8. A vinyl chloride copolymer prepared by the preparation method of claim 1 ,
wherein the vinyl chloride copolymer comprises a part derived from an N-substituted maleimide based monomer in an amount ratio between 5 wt % and 30 wt %.

9. The vinyl chloride copolymer of claim 8 , wherein the N-substituted maleimide based monomer is N-phenyl maleimide.

10. The vinyl chloride copolymer of claim 8 , wherein the vinyl chloride copolymer has a glass transition temperature (Tg) in a temperature range between 100° C. and 120° C.

11. The vinyl chloride copolymer of claim 8 , wherein the vinyl chloride copolymer has a heat deformation temperature (HDT) in a temperature range between 92° C. and 110° C.

Assignees

• Lg Chemical Ltd

Inventors

• Ju Jin Hyuck
• Ha Hyun Kyou
• Lim Joong Chul
• Jeon Yang Jun
• Kang Min Jeong

Classifications

• C08F222/40

  Imides, e.g. cyclic imides · CPC title

• C08G73/12

  Unsaturated polyimide precursors · CPC title

• C08F214/06 Primary

  Vinyl chloride · CPC title

• C08F259/04

  on to polymers of vinyl chloride · CPC title

• C08F290/062

  Polyethers · CPC title