Vinyl resin production method

Patent metadata

Field	Value
Publication number	US-9751963-B2
Application number	US-201515302281-A
Country	US
Kind code	B2
Filing date	Apr 8, 2015
Priority date	Apr 9, 2014
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A dispersion stabilizer in the present invention contains an aqueous emulsion (a) obtained by dispersing a polymer (A) having an ethylenically unsaturated monomer unit in an aqueous medium, a PVA (B) having a degree of saponification of 65 mol % or more and less than 82 mol % and a viscosity-average degree of polymerization of 250 or more and less than 1500, and a PVA (C) having a degree of saponification of 82 mol % or more and less than 98 mol % and a viscosity-average degree of polymerization of 1500 or more and less than 4000. The dispersion stabilizer contains: 7 to 51 mass % of the polymer (A); 40 to 84 mass % of the PVA (B); and 9 to 53 mass % of the PVA (C), with respect to a total amount of the polymer (A), the PVA (B), and the PVA (C). A vinyl resin satisfying required performance can be obtained using the dispersion stabilizer.

First claim

The invention claimed is:

1. A method for producing a vinyl resin, comprising:
suspension polymerizing of a vinyl compound in an aqueous medium using a dispersion stabilizer,
wherein the dispersion stabilizer comprises:
an aqueous emulsion (a) obtained by dispersing a polymer (A) having an ethylenically unsaturated monomer unit in an aqueous medium;
a polyvinyl alcohol (B) with a degree of saponification of 65 mol % or more and less than 82 mol % and a viscosity-average degree of polymerization of 250 or more and less than 1,500; and
a polyvinyl alcohol (C) with a degree of saponification of 82 mol % or more and less than 98 mol % and a viscosity-average degree of polymerization of 1,500 or more and less than 4,000;
wherein the dispersion stabilizer comprises: 7 to 51 mass % of the polymer (A); 40 to 84 mass % of the polyvinyl alcohol (B); and 9 to 53 mass % of the polyvinyl alcohol (C), with respect to a total amount of the polymer (A), the polyvinyl alcohol (B), and the polyvinyl alcohol (C).

2. The production method according to claim 1 , wherein a solid content of the aqueous emulsion (a) is 35 to 70 mass %.

3. The production method according to claim 1 , wherein the polymer (A) includes a polyvinyl ester.

4. The production method according to claim 3 , wherein the polyvinyl ester is polyvinyl acetate.

5. The production method according to claim 1 , wherein a block character of residual vinyl ester groups in each of the polyvinyl alcohol (B) and the polyvinyl alcohol (C) is 0.55 or less.

6. The production method according to claim 1 , wherein a mass ratio of the vinyl compound with respect to the aqueous medium is 0.57 to 1.25.

Assignees

• Kuraray Co
• Kuraray Europe Gmbh

Inventors

• Fukuhara Tadahito
• Kumaki Yosuke
• Michel Samuel
• Hartmann Dirk

Classifications

• C08F2400/00

  Characteristics for processes of polymerization · CPC title

• C08F114/06 Primary

  Vinyl chloride · CPC title

• C08F2/18

  Suspension polymerisation · CPC title

• C08F2/20 Primary

  with the aid of macromolecular dispersing agents · CPC title

• C08F14/06

  Vinyl chloride · CPC title