Method for producing polycarbamate, a polycarbamate produced thereby and a coating containing the polycarbamate

Patent metadata

Field	Value
Publication number	US-10196484-B2
Application number	US-201414916555-A
Country	US
Kind code	B2
Filing date	Sep 18, 2014
Priority date	Sep 17, 2013
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A method for producing polycarbamate comprising: contacting at least one carbamylating agent with a polyol in the presence of a carbamylation catalyst to form a reaction mixture having an acid value from 3 to 50 mg KOH/g dry polyol is provided. Further provided are a polycarbamate produced by the method and a coating comprising the polycarbamate.

First claim

The invention claimed is:

1. A method for producing polycarbamate comprising:
contacting urea with from 30 to 70% by weight of an acrylic polyol in the presence of a carbamylation catalyst and in the presence of one or more external components having one or more functionalities selected from the group consisting of acid functionalities and functionalities which become acidic in the reaction mixture to form a reaction mixture having an acid value from 15 to 50 mg KOH/g dry polyol, wherein said carbamylation catalyst is selected from dibutyltin oxide, butyltin oxide and dibutyltin diacetate thereby producing a polycarbamate, wherein the polycarbamate has a molecular weight, Mw, which is no higher than twice the Mw of the starting polyol.

2. The method according to claim 1 , wherein the polyol comprises units derived from one or more monomers having one or more functionalities selected from the group consisting of acid functionalities and functionalities which become acidic in the reaction mixture.

3. The method according to claim 1 , wherein the acrylic polyol comprises units derived from one or more monomers selected from the group consisting of 2-ethylhexyl acrylate, methyl methacrylate, and 2-hydroxyethyl methacrylate.

4. The method according to claim 1 , wherein the carbamylation catalyst is dibutyltin oxide.

5. The method according to claim 1 , wherein the urea is present as an aqueous solution of urea.

6. The method according to claim 1 , wherein at least 70 mol % of hydroxyl groups of the polyol are converted.

7. The method according to claim 1 , wherein the external component is benzoic acid.

8. A polycarbamate produced according to the method of claim 1 , wherein the polycarbamate has a polydispersity which is no higher than twice the polydispersity of the starting polyol.

9. A coating comprising a polycarbamate produced according to the method of claim 1 .

Assignees

• Dow Global Technologies Llc

Inventors

• Spilman Gary E
• Lu Congcong
• Beigzadeh Jr Daryoosh
• He Yiyong
• Popa Paul J
• Argyropoulos John N

Classifications

• C08G71/04 Primary

  Polyurethanes · CPC title

• C08G18/6229

  Polymers of hydroxy groups containing esters of acrylic or methacrylic acid with aliphatic polyalcohols · CPC title

• C08G18/6254

  Polymers of alpha-beta ethylenically unsaturated carboxylic acids and of esters of these acids containing hydroxy groups · CPC title

• C09D175/06

  from polyesters · CPC title