Modified vinyl alcohol-based polymer, and dispersion stabilizer for suspension polymerization

Patent metadata

Field	Value
Publication number	US-10836843-B2
Application number	US-201716320032-A
Country	US
Kind code	B2
Filing date	Aug 22, 2017
Priority date	Aug 25, 2016
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

An object of the present invention is to provide a dispersion stabilizer for suspension polymerization which satisfies various performance requirements for suspension polymerization of a vinyl-based compound such as vinyl chloride. The present invention relates a modified vinyl alcohol-based polymer having at least one monomer unit represented by a following general formula (I) and a modification rate of from 0.01 mol % to 10 mol %:
general formula (1)

in which BO represents an oxybutylene unit; EO represents an oxyethylene unit; and each of m and n is a number of repeating unit of the respective oxyalkylene units; 1≤m≤10; and 1≤n≥60.

First claim

What is claimed is:

1. A modified vinyl alcohol-based polymer having at least one monomer unit represented by the following general formula (I) and a modification rate of from 0.01 mol % to 10 mol %:

in which BO represents an oxybutylene unit; EO represents an oxyethylene unit; and each of m and n is a number of repeating unit of the respective oxyalkylene units; 1≤m≤10; and 1≤n≤60.

2. The modified vinyl alcohol-based polymer according to claim 1 , wherein the modified vinyl alcohol-based polymer has a viscosity average polymerization degree of from 300 to 5000.

3. The modified vinyl alcohol-based polymer according to claim 1 , wherein the modified vinyl alcohol-based polymer has a saponification degree of from 60 mol % to 99.9 mol %.

4. The modified vinyl alcohol-based polymer according to claim 1 , wherein the modified vinyl alcohol-based polymer has a viscosity average polymerization degree of 1000 or less.

5. The modified vinyl alcohol-based polymer according to claim 1 , wherein the modified vinyl alcohol-based polymer has a saponification degree of from 65 mol % to 80 mol %.

6. A dispersion stabilizer for suspension polymerization, comprising the modified vinyl alcohol-based polymer according to claim 1 .

7. A method for producing a vinyl resin, comprising: dispersing a vinyl-based compound monomer or a mixture of the vinyl-based compound monomer and a monomer that is copolymerizable with the vinyl compound monomer in water with the dispersion stabilizer for suspension polymerization according to claim 6 , and carrying out suspension polymerization.

Assignees

• Denka Company Ltd

Inventors

• Watanabe Wataru

Classifications

• C08F290/062

  Polyethers · CPC title

• C08F218/08

  Vinyl acetate · CPC title

• C08F216/06

  Polyvinyl alcohol {; Vinyl alcohol} · CPC title

• C08F14/06

  Vinyl chloride · CPC title

• C08L31/00

  Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, of carbonic acid or of a haloformic acid (of hydrolysed polymers C08L29/00); Compositions of derivatives of such polymers · CPC title