Self-Stratifying Automotive Topcoat Compositions and Processes

• US 20100087596A1
• Filed: 10/08/2008
• Published: 04/08/2010
• Est. Priority Date: 10/08/2008
• Status: Active Grant

• Current Assignee: Eastern Michigan University, Toyota Motor Corporation
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Hernandez, Heidi Rosalia Perez, Templeman, Cynthia Gazepis, Baghdachi, Jamil
• Granted Patent: US 7,863,375 B2
• Time in Patent Office: Days
• US Class Current: 524/728
• CPC Class Codes: C08G 18/3893 containing silicon
• CPC Class Codes: C08G 18/6275 Polymers of halogen containing compounds having carbon-to-carbon double bonds; halogenated polymers of compounds having carbon-to-carbon double bonds C08G18/6212 takes precedence
• CPC Class Codes: C08G 18/792 formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
• CPC Class Codes: C08G 77/14 containing silicon bound to oxygen-containing groups C08G77/045 takes precedence
• CPC Class Codes: C08K 5/1535 Five-membered rings
• CPC Class Codes: C09D 175/04 Polyurethanes
• CPC Class Codes: C09D 183/04 Polysiloxanes
• CPC Class Codes: C09D 183/06 containing silicon bound to oxygen-containing groups C09D183/12 takes precedence

Abstract

A process for preparing a coating composition includes contacting a polyol, a silsesquioxane, a polyurethane dendrimer, and a crosslinker, wherein the polyol, the silsesquioxane, the polyurethane dendrimer, and the crosslinker are dispersed within a solvent and forming a self-stratifying coating. Further, a coating composition includes a polyol, a silsesquioxane, a polyurethane dendrimer and a crosslinker forming a mixture dispersed within a solvent.

Claims

1. A process for preparing a coating composition, the process comprising:

contacting a polyol, a silsesquioxane, a polyurethane dendrimer, and a crosslinker, wherein the polyol, the silsesquioxane, the polyurethane dendrimer, and the crosslinker are dispersed within a solvent; and

forming a self-stratifying coating.

2. The process of claim 1, wherein the polyol is selected from the group consisting of a fluorinated polyether, a fluoroethylene-alkyl vinyl ether and a combination thereof.

3. The process of claim 1, wherein the silsesquioxane is an epoxy functional silsesquioxane having a formula (R)₆(C₆H₁₁O₂)₂(SiO_1.5)₈, wherein R is selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclopentyl, cyclohexyl, benzyl, phenyl and isomers thereof.

4. The process of claim 3, wherein the epoxy functional silsesquioxane is a diepoxy silsesquioxane.

5. The process of claim 1, wherein the polyurethane dendrimer is selected from the group consisting of isophorone diisocyanate (IPDI), isophorone triisocyanate (IPTI), and a combination thereof.

6. The process of claim 1y wherein the crosslinker is an isocyanate-functional compound selected from the group consisting of hexamethylene diisocyanate (HDI), hexamethylene triisocyanate (HTI), methylene bis-(4-cyclohexyl isocyanate) (HMDI) and a combination thereof.

7. The process of claim 1 further comprising removing the solvent.

8. The process of claim 7, wherein the solvent is selected from the group consisting of tetrahydrofuran (THF), dimethylacetamide (DMA) and a combination thereof.

9. The process of claim 7, wherein removing the solvent comprises evaporating the solvent.

10. A coating composition comprising:

a polyol, a silsesquioxane, a polyurethane dendrimer and a crosslinker forming a mixture dispersed within a solvent.

11. The composition of claim 10, wherein the polyol is selected from the group consisting of a fluorinated polyether, a fluoroethylene-alkyl vinyl ether and a combination thereof.

12. The composition of claim 10, wherein the silsesquioxane is an epoxy functional silsesquioxane having a formula (R)₆(C₆H₁₁O₂)₂(SiO_1.5)₈, wherein R is selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, cyclopentyl, cyclohexyl, benzyl, phenyl and isomers thereof.

13. The composition of claim 12, wherein the epoxy functional silsesquioxane is a diepoxy silsesquioxane.

14. The composition of claim 10, wherein the polyurethane dendrimer is selected from the group consisting of isophorone diisocyanate (IPDI), isophorone triisocyanate (IPTI) and a combination thereof.

15. The composition of claim 10, wherein the crosslinker is an isocyanate-functional compound selected from the group consisting of hexamethylene diisocyanate (HDI), hexamethylene triisocyanate (HTI), methylene bis-(4-cyclohexyl isocyanate) (HMDI) and a combination thereof.

16. The composition of claim 10, wherein the solvent is selected from the group consisting of tetrahydrofuran (THF), dimethylacetamide (DMA) and a combination thereof.

17. The composition of claim 105 wherein the solvent is removed to form a self-stratifying coating composition.