Polyesters and coatings containing the same

Patent metadata

Field	Value
Publication number	US-9359524-B2
Application number	US-201314054126-A
Country	US
Kind code	B2
Filing date	Oct 15, 2013
Priority date	Oct 15, 2013
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

Disclosed is a polyester prepared from a mixture of reactants including: a) an aromatic monoacid, where the aromatic monoacid includes from 25 to 60 weight % based on the total weight of reactants; b) a polyacid, where the polyacid includes less than 90 mole % isophthalic acid; and c) a polyol having at least 3 hydroxyl groups. The mixture of reactants is substantially free of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301 rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s −1 ), and an acid value of less than 15 mg KOH/g. The polyacid can also be an aliphatic polyacid. Coatings comprising the same and substrates coated at least in part with such coatings are also disclosed.

First claim

The invention claimed is:

1. A polyester prepared from a mixture of reactants comprising:
a) an aromatic monoacid, wherein the aromatic monoacid comprises from 25 to 60 weight % based on the total weight of reactants;
b) a polyacid, wherein the polyacid comprises less than 90 mole % isophthalic acid; and
c) a polyol comprising at least 3 hydroxyl groups,
wherein the mixture of reactants contain less than 1000 parts per million of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301 rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s −1 ), an acid value of less than 15 mg KOH/g, and a glass transition temperature of less than 0° C.

2. A polyester prepared from a mixture of reactants consisting essentially of:
a) an aromatic monoacid, wherein the aromatic monoacid comprises from 25 to 60 weight % based on the total weight of reactants;
b) a polyacid, wherein the polyacid comprises less than 90 mole % isophthalic acid; and
c) a polyol comprising at least 3 hydroxyl groups,
wherein the mixture of reactants contain less than 1000 parts per million of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301 rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s −1 ), an acid value of less than 15 mg KOH/g, and a glass transition temperature of less than 0° C.

3. A polyester prepared from a mixture of reactants comprising:
a) an aromatic monoacid, wherein the aromatic monoacid comprises from 25 to 60 weight % based on the total weight of reactants;
b) an aliphatic polyacid; and
c) a polyol comprising at least 3 hydroxyl groups,
wherein the mixture of reactants contain less than 1000 parts per million of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s −1 ), an acid value of less than 15 mg KOH/g, and a glass transition temperature of less than 0° C.

4. A coating composition comprising:
a) a polyester prepared from a mixture of reactants comprising:
1) an aromatic monoacid, wherein the aromatic monoacid comprises from 25 to 60 weight % based on the total weight of reactants;
2) an aliphatic polyacid; and
3) a polyol comprising at least 3 hydroxyl groups,
wherein the mixture of reactants contain less than 1000 parts per million of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301 rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s 31 1 ), an acid value of less than 15 mg KOH/g; and a glass transition temperature of less then 0° C.; and

b) a crosslinker.

5. A coating composition comprising:
a) a polyester prepared from a mixture of reactants comprising:
1) an aromatic monoacid, wherein the aromatic monoacid comprises from 25 to 60 weight % based on the total weight of reactants;
2) a polyacid, wherein the polyacid comprises less than 90 mole % isophthalic acid; and
3) a polyol comprising at least 3 hydroxyl groups,
wherein the mixture of reactants contain less than 1000 parts per million of a non-aromatic monoacid, and said polyester has a dynamic viscosity of greater than 15,000 centipoise at 40° C. as measured by a Physica MCR 301 rheometer with 25 mm parallel plate and 0.1 mm gap as a function of increasing shear rate (0.1 to 10 s −1 ), an acid value of less than 15 mg KOH/g; and a glass transition temperature of less then 0° C.; and

b) a crosslinker.

6. The coating composition of claim 5 , wherein the mixture of reactants contain less than 20 parts per billion of an non-aromatic monoacid.

7. The coating composition of claim 5 , wherein the coating composition contains less than 1000 parts per million of water.

8. The coating composition of claim 5 , wherein the coating composition contains less than 20 parts per billion of water.

9. A substrate at least partially coated with the coating composition of claim 5 .

10. The coating composition of claim 5 , wherein the polyol comprises from 25 to 60 weight % based on the total weight of the reactants.

11. The coating composition of claim 5 , wherein the aromatic monoacid comprises benzoic acid, salicylic acid, 4-hydroxyl benzoic acid, or mixtures thereof.

12. The coating composition of claim 5 , wherein the polyacid comprises succinic acid, adipic acid, hexahydrophthalic anhydride (HHPA), cyclohexanedicarboxylic acid (CHDA), or mixtures thereof.

13. The coating composition of claim 5 , wherein the polyol comprises trimethylolpropane, glycerol, pentaerythritol, or mixtures thereof.

14. The coating composition of claim 5 , wherein the polyacid comprises from 10 to 30 weight % based on the total weight of the reactants.

15. The coating composition of claim 5 , wherein the mixture of reactants further comprise a second polyol comprising 2 hydroxyl groups.

16. The coating composition of claim 5 , wherein the polyester has a hydroxyl value of 140 to 340 mg KOH/g.

17. The coating composition of claim 5 , wherein the polyester has a weight average molecular weight of less than or equal to 2,500 g/mol.

18. The coating composition of claim 5 , wherein the polyacid comprises 10 carbons or less.

Assignees

• Ppg Ind Ohio Inc

Inventors

• Breon Jonathan P
• Maksimovic Ljiljana
• Chasser Anthony M
• Millero Edward R
• Schwendeman John E
• Jennings Robert E

Classifications

• C09D167/02

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C09D167/06 takes precedence) · CPC title

• C08G63/06

  derived from hydroxycarboxylic acids · CPC title

• C08G63/12 Primary

  derived from polycarboxylic acids and polyhydroxy compounds · CPC title

• C08G63/199

  Acids or hydroxy compounds containing cycloaliphatic rings · CPC title

• C08G63/16

  Dicarboxylic acids and dihydroxy compounds · CPC title