Water-dispersible polyurethane-vinyl polymer compositions

• US 7,968,641 B2
• Filed: 02/24/2009
• Issued: 06/28/2011
• Est. Priority Date: 08/13/2003
• Status: Active Grant

• Current Assignee: Swimc, LLC (The Sherwin-Williams Company)
• Original Assignee: Valspar Sourcing, Inc. (Sherwin-Williams Company)
• Inventors: Killilea, T. Howard
• Primary Examiner(s): NILAND, PATRICK DENNIS
• Application Number:
  US12/391,916
• Publication Number:
  US 20090163651A1
• Time in Patent Office: 854 Days
• Field of Search: 524/507, 524/591, 524/839, 524/840, 525/123, 525/455, 525/440.01, 525/440.07, 525/440.072, 525/458
• US Class Current: 524/507
• CPC Class Codes: C08F 265/04 on to polymers of esters
• CPC Class Codes: C08F 265/06 Polymerisation of acrylate or methacrylate esters on to polymers thereof
• CPC Class Codes: C08F 290/067 Polyurethanes; Polyureas
• CPC Class Codes: C08G 18/0828 containing sulfonate groups or groups forming them
• CPC Class Codes: C08G 18/0866 the dispersing or dispersed phase being an aqueous medium
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/3228 acyclic
• CPC Class Codes: C08G 18/4288 modified by higher fatty oils or their acids or by resin acids
• CPC Class Codes: C08G 18/4676 containing sulfur
• CPC Class Codes: C08G 18/683 containing cyclic groups
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 33/12 Homopolymers or copolymers of methyl methacrylate
• CPC Class Codes: C08L 51/003 grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C08L51/04, C08L51/06 take precedence
• CPC Class Codes: C09D 175/06 from polyesters
• CPC Class Codes: C09D 175/14 Polyurethanes having carbon-to-carbon unsaturated bonds

Abstract

A polyurethane dispersion is prepared by reacting a hydroxy-functional sulfonated unsaturated alkyd with an isocyanate in the presence of one or more vinyl monomers to form a blend containing the vinyl monomers and a sulfonated polyurethane polymer containing ethylenic groups. The blend is dispersed in water and the vinyl monomers are reacted by free radical polymerization.

Claims

1. A process for preparing a polyurethane dispersion, which process comprises:

a) providing a reaction mixture comprising a hydroxy-functional sulfonated unsaturated alkyd, an isocyanate and one or more vinyl monomers, thereby forming a blend containing the vinyl monomers and a sulfonated polyurethane polymer containing ethylenic groups;

a) dispersing the blend in water; and

b) reacting the vinyl monomers by free radical polymerization.

2. A process according to claim 1 wherein the hydroxy-functional sulfonated unsaturated alkyd is derived from linseed oil, safflower oil, tall oil, cottonseed oil, ground nut oil, tung oil, wood oil, ricinene oil, sunflower oil, soya oil, castor oil, dehydrated castor oil, soya fatty acid, dehydrated castor fatty acid, linolenic fatty acid, ricinoleic fatty acid or linoleic fatty acid.

3. A process according to claim 1 wherein the hydroxy-functional sulfonated unsaturated alkyd is derived from a sulfonated dicarboxylic acid.

4. A process according to claim 3 wherein the sulfonated dicarboxylic acid comprises 5-(sodiosulfo)isophthalic acid or 5-(lithiosulfo)isophthalic acid.

5. A process according to claim 1 wherein the sulfonated polyurethane polymer contains sulfonate groups in the form of lithium, sodium or potassium alkali metal salts.

6. A process according to claim 1 wherein the one or more vinyl monomers comprise acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, 2-(acetoacetoxy)ethylmethacrylate, acrylamide, methylacrylamide, diacetone acrylamide, styrene, α

-methyl styrene, vinyl toluene, vinyl acetate, vinyl propionate or mixture thereof and wherein the one or more vinyl monomers react by free radical polymerization to form a polymer with pendant acetoacetate, diacetoneacrylamido, acetyl or benzoyl groups that can crosslink using unsaturation present on an alkyd portion of the sulfonated polyurethane polymer.

7. A process according to claim 1 wherein the sulfonated polyurethane polymer has terminal vinyl groups.

8. A process according to claim 1 wherein the sulfonated polyurethane polymer has terminal isocyanate groups.

9. A process according to claim 8 further comprising chain extending the terminal isocyanate groups with one or more active hydrogen containing compounds.

10. A process according to claim 9 wherein the one or more active hydrogen containing compounds comprise an alkyl amino alcohol, cycloalkyl amino alcohol, heterocyclic amino alcohol, polyamine, hydrazine or hydrazines, hydrazide, amide, water, ethylene diamine, diethylene triamine, triethylene tetra amine, melamine or a mixture thereof.

11. A process according to claim 9 wherein the one or more active hydrogen containing compounds comprise a polyalkene oxide, hydroxyl functional latex or amine functional latex.

12. A process according to claim 1 wherein the sulfonated polyurethane polymer has a hydroxy number of from about 0 to about 150.

13. A process according to claim 1 further comprising adding a metal salt drier to the polyurethane dispersion.

14. A process according to claim 1 wherein the polyurethane dispersion is air-curable at room temperature.

15. A reaction mixture for use in the process of claim 1, comprising:

a) a hydroxy-functional sulfonated unsaturated alkyd;

b) an isocyanate; and

c) one or more vinyl monomers.

16. A reaction mixture according to claim 15 wherein the hydroxy-functional sulfonated unsaturated alkyd is derived from linseed oil, safflower oil, tall oil, cottonseed oil, ground nut oil, tung oil, wood oil, ricinene oil, sunflower oil, soya oil, castor oil, dehydrated castor oil, soya fatty acid, dehydrated castor fatty acid, linolenic fatty acid, ricinoleic fatty acid or linoleic fatty acid.

17. A reaction mixture according to claim 15 wherein the hydroxy-functional sulfonated unsaturated alkyd is derived from 5-(sodiosulfo)isophthalic acid or 5-(lithiosulfo)isophthalic acid.

18. A reaction mixture according to claim 15 wherein the one or more vinyl monomers react by free radical polymerization to form a polymer with pendant acetoacetate, diacetoneacrylamido, acetyl or benzoyl groups that can crosslink using unsaturation present on an alkyd portion of the sulfonated polyurethane polymer.

19. A reaction mixture according to claim 15 wherein the sulfonated polyurethane polymer has terminal isocyanate groups.

20. A reaction mixture according to claim 19 further comprising a chain extension agent containing active hydrogen atoms.

21. A reaction mixture according to claim 20 wherein the chain extension agent comprises an alkyl amino alcohol, cycloalkyl amino alcohol, heterocyclic amino alcohol, polyamine, hydrazine, substituted hydrazine, or hydrazines, hydrazide, amide, water, ethylene diamine, diethylene triamine, triethylene tetra amine, melamine or a mixture thereof.

22. A reaction mixture according to claim 15 wherein the isocyanate comprises an aromatic isocyanate.

23. A process according to claim 1 wherein the isocyanate comprises an aromatic isocyanate.