POLYURETHANE-UREA POLYMERS DERIVED FROM CYCLOHEXANE DIMETHANOL

• US 20090253858A1
• Filed: 05/17/2007
• Published: 10/08/2009
• Est. Priority Date: 05/18/2006
• Status: Active Grant

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Inventors: Argyropoulos, John N., Bhattacharjee, Debkumar
• Granted Patent: US 8,022,138 B2
• Time in Patent Office: Days
• US Class Current: 524/591
• CPC Class Codes: C08G 18/0823 containing carboxylate salt groups or groups forming them
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/246 containing also tin-carbon bonds
• CPC Class Codes: C08G 18/3228 acyclic
• CPC Class Codes: C08G 18/4238 derived from dicarboxylic acids and dialcohols
• CPC Class Codes: C08G 18/6659 with compounds of group C08G18/34
• CPC Class Codes: C08G 18/755 and at least one isocyanate or isothiocyanate group linked to a secondary carbon atom of the cycloaliphatic ring, e.g. isophorone diisocyanate
• CPC Class Codes: C09D 175/06 from polyesters

Abstract

Aqueous polyurethane dispersion are disclosed where the dispersions contain from 5 to 70 weight percent polyurethane solids wherein the solids are obtained from at least one isocyanate terminated prepolymer prepared by reacting (a) a polyol or polyol blend having a mean average equivalent weight of 200 to 2,000; and (b) at least one polyisocyanate where the prepolymer is dispersed in water; optionally in the presence of (c) one or more stabilizers; or (d) one or more amine chain extenders or both; wherein the prepolymers have an isocyanate (NCO) content of from 2 to 40 weight percent and the polyol or polyol blend (a) contains at least 15 weight percent of a polyester based on a polycarboxylic acid or lactone component and a glycol component, wherein the glycol component contains isomers of 1,3- and 1,4-cyclohexanedimethanol (1,3-/1,4-CHDM) where the ratio of the 1,3-/1,4-isomers is from 35:65 to 65:35.

Claims

1. An aqueous polyurethane dispersion containing from 5 to 70 weight percent polyurethane solids wherein the solids are obtained from at least one isocyanate terminated prepolymer prepared by reacting

(a) a polyol or polyol blend having a mean average equivalent weight of 200 to 2,000;

and

(b) at least one polyisocyanate where the prepolymer is dispersed in water;

optionally in the presence of

(c) one or more stabilizers;

or

(d) one or more amine chain extenders or both;

wherein the prepolymers have an isocyanate (NCO) content of from 2 to 40 weight percent and the polyol or polyol blend (a) contains at least 15 weight percent of a polyester based on a polycarboxylic acid or lactone component and a glycol component, wherein the glycol component contains isomers of 1,3- and 1,4-cyclohexanedimethanol (1,3-/1,4-CHDM) where the ratio of the 1,3-/1,4-isomers is from 35;

65 to 65;

35.

2. The dispersion of claim 1 wherein the solids content is from 40 to 60 weight percent.

3. The dispersion of claims 1 wherein the polyisocyanate is an aliphatic isocyanate.

4. The dispersion of claim 3 wherein the isocyanate is 1,6-hexamethylene-diisocyanate;

isophorone diisocyanate, 1,3-, 1,4-bis(isocyanatomethyl)cyclohexane or a mixture thereof.

5. The dispersion of claim 1 wherein the polyisocyanate is an aromatic isocyanate.

6. The dispersion of claim 5 wherein the isocyanate is 2,4- or 2,-6-toluenediisocyanate, 4,4′

, 2,4′

or 2,2′

-diphenylmethanediisocyanate or a mixture of such isomers, polyphenyl polymethylene polyisocyanate or a mixture thereof.

7. The dispersion of claim 6 wherein the isocyanate is diphenylmethanediisocyanate.

8. The dispersion of claim 1 wherein the prepolymer and dispersion are prepared in the absence of an organic solvent.

9. The dispersion of any one of the preceding claims wherein the polyol or polyol blend has an average mean equivalent weight of 300 to 1500

10. This dispersion of claim 9 wherein the polyol or polyol blend has an average mean equivalent weight of 400 to 1200.

11. The dispersion of claim 1 wherein the polyester based on 1,3,-/1,4-CHDM comprises at least 50 weight percent of the total polyol component.

12. The dispersion of claim 1 wherein the prepolymer is made in the presence of a solvent and the solvent is substantially removed prior to dispersion of the prepolymer in water.

13. The dispersion of any of the preceding claims wherein the dispersion is made in a continuous process.

14. The use of the polyurethane dispersion of claim 1 for a coating on a substrate.

15. The use of claim 14 wherein the substrate is a hard surface.

16. The use of claim 15 wherein the substrate is wood or metal.

17. A polyurethane polymer derived from the dispersion of claim 1.

18. The polymer of claim 17 wherein the polyurethane polymer is a coating, adhesive, sealant, elastomer or foam.