Dual stabilized dispersions of gelled polymeric microparticles and coatings produced therefrom

• US 6,372,840 B1
• Filed: 06/28/2000
• Issued: 04/16/2002
• Est. Priority Date: 06/28/1999
• Status: Expired due to Fees

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Steppan, Susana C., Mayo, Michael A., Shalati, Mohamad D.
• Primary Examiner(s): Wu, David W.
• Assistant Examiner(s): EGWIM, KELECHI CHIDI
• Application Number:
  US09/605,451
• Time in Patent Office: 657 Days
• Field of Search: 524/461, 524/513, 524/539, 524/566, 524/504, 524/923, 525/7, 525/7.1, 525/69, 525/167.5
• US Class Current: 524/504
• CPC Class Codes: C08F 2/08 with the aid of dispersing agents for the polymer
• CPC Class Codes: Y10S 524/923 Treating or preparing a nonaqueous dispersion or emulsion of a solid polymer or specified intermediate condensation product

Abstract

In a dispersion containing acrylic polymer microparticles, particularly useful in automotive coatings, the dispersion is formed by free radical addition copolymerization of unsaturated monomers in a hydrocarbon dispersing medium in the presence of first and second polymeric dispersion stabilizers. The first polymeric dispersion stabilizer has an acrylic backbone and polyester side chains, and the second polymeric dispersion stabilizer is a branched polyester formed from the reaction of polyol, polyacid or anhydride, and fatty acid.

Claims

1. A dispersion containing acrylic polymer microparticles, the dispersion being formed by free radical addition copolymerization of unsaturated monomers in hydrocarbon dispersing liquid in the presence of first and second polymeric dispersion stabilizers, the first polymeric dispersion stabilizer having an acrylic backbone and polyester side chains, and the second polymeric dispersion stabilizer being a branched polyester formed from the reaction of polyol, polyacid or anhydride, and fatty acid.

2. The dispersion of claim 1 wherein the polyester side chains of the first dispersion stabilizer comprise groups derived from poly(hydroxystearic acid).

3. The dispersion of claim 1 wherein the polyol component of the second polymeric dispersion stabilizer has an average of greater than 2.0 hydroxyl groups per molecule.

4. The dispersion of claim 1 wherein the polyol component of the second polymeric dispersion stabilizer has an average of greater than 3.0 hydroxyl groups per molecule.

5. The dispersion of claim 4 wherein the polyol component of the second polymeric dispersion stabilizer comprises trimethylol propane and pentaerythritol.

6. The dispersion of claim 3 wherein the fatty acid component of the second polymeric dispersion stabilizer fatty acid comprises isostearic acid.

7. The dispersion of claim 6 wherein the diacid or anhyride component of the second polymeric dispersion stabilizer comprises hexahydrophthalic anhydrid.

8. The dispersion of claim 1 wherein the second polymeric dispersion stabilizer is present in larger amounts by weight than the first polymeric dispersion stabilizer.