Method for producing polycarboxylic acid polymer

Patent metadata

Field	Value
Publication number	US-10214605-B2
Application number	US-201515515200-A
Country	US
Kind code	B2
Filing date	Sep 18, 2015
Priority date	Sep 30, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

Provided is a method of producing a polycarboxylic acid-based polymer, the method including adding a monomer composition containing an unsaturated monocarboxylic acid-based monomer and/or an unsaturated dicarboxylic acid-based monomer to a reaction vessel to perform a polymerization reaction, which enables effective suppression of the foaming of a polymerization reaction liquid. The method of producing a polycarboxylic acid-based polymer of the present invention is a method of producing a polycarboxylic acid-based polymer, the method including adding a monomer composition containing an unsaturated monocarboxylic acid-based monomer and/or an unsaturated dicarboxylic acid-based monomer to a reaction vessel to perform a polymerization reaction, the method further including adding a defoaming agent by a time when 100 mass % of a total amount of the monomer composition is added.

First claim

What is claimed is:

1. A method of producing a polycarboxylic acid-based polymer, comprising adding a monomer composition containing (meth)acrylic acid and/or salts thereof, a monomer composition containing maleic acid and/or salts thereof, a monomer composition containing (meth)acrylic acid and/or salts thereof and a sulfonic group-containing compound, a monomer composition containing maleic acid and/or salts thereof and a sulfonic group-containing compound, or a monomer composition containing (meth)acrylic acid and/or salts thereof, maleic acid and/or salts thereof and a sulfonic group-containing compound to a reaction vessel to perform a polymerization reaction,
wherein the polycarboxylic acid-based polymer is a homopolymer of poly(meth)acrylic acid and/or salts thereof, a homopolymer of polymaleic acid and/or salts thereof, a copolymer of (meth)acrylic acid and/or salts thereof and a sulfonic group-containing compound, a copolymer of maleic acid and/or salts thereof and a sulfonic group-containing compound, or a copolymer of (meth)acrylic acid and/or salts thereof, maleic acid and/or salts thereof and a sulfonic group-containing compound,
the method further comprising adding a defoaming agent by a time when 100 mass % of a total amount of the monomer composition is added.

2. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein an addition amount of the defoaming agent is from 1 ppm to 10,000 ppm with respect to the total amount of the monomer composition.

3. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein a total amount of the defoaming agent is initially loaded into the reaction vessel.

4. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein the defoaming agent comprises an oxyalkylene-based defoaming agent.

5. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein the polymerization reaction is performed by using hydrogen peroxide as a polymerization initiator.

6. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein the polycarboxylic acid-based polymer is a copolymer of (meth)acrylic acid and/or salts thereof and a sulfonic group-containing compound, or a copolymer of (meth)acrylic acid and/or salts thereof, maleic acid and/or salts thereof and a sulfonic group-containing compound.

7. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein a polymerization pressure for the polymerization reaction is under normal pressure.

8. The method of producing a polycarboxylic acid-based polymer according to claim 1 , wherein a polymerization temperature for the polymerization reaction is 70° C. to a boiling point of the monomer composition.

Assignees

• Nippon Catalytic Chem Ind

Inventors

• Sano Yuki
• Tsumori Takahiro
• Kanzaki Akihiko

Classifications

• C08F20/00

  Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof · CPC title

• C08F220/06 Primary

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

• C08F2/10

  Aqueous solvent · CPC title

• C08F220/08

  Anhydrides · CPC title

• C08F222/06

  Maleic anhydride · CPC title