Powder coating compositions containing glycidyl ester copolymers and carboxyl terminated crosslinking agent

Claim 2

A powder coating composition which, exclusive of pigments and other non-reactive components, comprises a coreactable mixture of: (A) a copolymer of about 8 to about 30 weight percent of a glycidyl ester of a monoethylenically unsaturated acid and about 92 to about 70 weight percent of other monoethylenically unsaturated monomers, said copolymer having a glass transition temperature in the range of 40° C to 90° C and a molecular weight (M n ) in the range of 2500 to 8500; and (B) a carboxyl terminated crosslinking agent in an amount ranging from about 0.8 to about 1.2 carboxyl groups for each epoxy group in the copolymer.

Claim 3

A powder coating composition in accordance with claim 1 wherein said copolymer has a glass transition temperature between about 50° C and about 80° C and a molecular weight (M n ) between about 3000 and about 6500, said glycidyl ester being present in said copolymer from at least about 10% by weight to no more than about 25% by weight.

Claim 4

A powder coating composition in accordance with claim 1 wherein said copolymer has a glass transition temperature between about 55° C and about 70° C and a molecular weight (M n ) in the range of about 3000 to about 4000, said glycidyl ester being present in said copolymer from at least about 12% by weight to no more than about 20% by weight.

Claim 5

A powder coating composition in accordance with claim 1 wherein said monoethylenically unsaturated monomers consist essentially of monofunctional, alpha-beta olefinically unsaturated monomers.

Claim 6

A powder coating composition in accordance with claim 4 wherein said monofunctional, alpha-beta olefinically unsaturated monomers are acrylates.

Claim 7

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a carboxyl terminated epoxy ester.

Claim 8

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a mixture of a carboxyl terminated epoxy ester and a saturated aliphatic, monocarboxylic acid, said monocarboxylic acid comprising up to 10 percent by equivalent weight of the mixture.

Claim 9

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a carboxyl terminated polyester.

Claim 10

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a carboxyl terminated polybutadiene resin.

Claim 11

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a carboxyl terminated butadiene-acrylonitrile random copolymer.

Claim 12

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprises a saturated, aliphatic dicarboxylic acid containing 4 to 20 carbon atoms.

Claim 13

A powder coating composition in accordance with claim 1 wherein said carboxyl terminated crosslinking agent comprising a mixture of 90 to 98 percent by equivalent weight of a saturated aliphatic dicarboxylic acid containing 4 to 20 carbon atoms and 2 to 10 percent by equivalent weight of a saturated aliphatic monocarboxylic acid containing 10 to 22 carbon atoms.

Claim 14

A powder coating composition which, exclusive of pigments and other non-reactive components, comprises a coreactable mixture of: (A) a copolymer of about 8 to about 30 weight percent of a glycidyl ester of a monoethylenically unsaturated acid and about 92 to about 70 weight percent of other monoethylenically unsaturated monomers, said copolymer having a glass transition temperature in the range of 40° C to 90° C and a molecular weight (M n ) in the range of 2500 to 8500; and (B) a carboxyl terminated crosslinking agent in an amount ranging from about 0.8 to about 1.2 carboxyl groups for each epoxy group in the copolymer, said crosslinking agent being selected from the group consisting of: (1) carboxyl terminated epoxy esters; (2) mixtures of carboxyl terminated epoxy esters and a saturated, aliphatic monocarboxylic acid comprising up to 10 percent by equivalent weight of the mixture; (3) carboxyl terminated polyesters; (4) carboxyl terminated polybutadiene, (5) carboxyl terminated random copolymers of butadiene and acrylonitrile; (6) saturated, aliphatic dicarboxylic acids containing 4 to 20 carbon atoms; (7) mixtures of 90 to 98 percent by equivalent weight of a saturated, aliphatic dicarboxylic acid containing 4 to 20 carbon atoms and 2 to 10 percent by equivalent weight of a saturated, aliphatic monocarboxylic acid containing 10 to 22 carbon atoms.

Claim 15

A powder coating composition which, exclusive of pigments and other non-reactive components, comprises a coreactable mixture of: (A) a copolymer of about 8 to about 30 weight percent of a glycidyl ester of a monoethylenically unsaturated acid and about 92 to about 70 weight percent of other monoethylenically unsaturated monomers, said copolymer having a glass transition temperature in the range of 40° C to 90° C and a molecular weight (M n ) in the range of 2500 to 8500; and (B) a carboxyl terminated crosslinking agent in an amount ranging from about 0.8 to about 1.2 carboxyl groups for each epoxy group in the copolymer, said crosslinking agent being selected from the group consisting of: (1) carboxyl terminated epoxy esters; (2) mixtures of carboxyl terminated epoxy esters and a saturated, aliphatic monocarboxylic acid comprising up to 10 percent by equivalent weight of the mixture; (3) carboxyl terminated polyesters; (4) carboxyl terminated polybutadiene, (5) carboxyl terminated random copolymers of butadiene and acrylonitrile; (6) saturated, aliphatic dicarboxylic acids containing 4 to 20 carbon atoms; (7) mixtures of 90 to 98 percent by equivalent weight of a saturated, aliphatic dicarboxylic acid containing 4 to 20 carbon atoms and 2 to 10 percent by equivalent weight of a saturated, aliphatic monocarboxylic acid containing 10 to 22 carbon atoms.

Claim 16

A powder coating composition in accordance with claim 13 wherein said copolymer has a glass transition temperature between about 50° C and about 80° C and a molecular weight (M n ) between about 3000 and about 6500, said glycidyl ester being present in said copolymer from at least about 10 percent to no more than about 25 percent by weight.

Claim 17

A powder coating composition in accordance with claim 13 wherein said copolymer has a glass transition temperature between about 55° C and about 70° C and a molecular weight (M n ) in the range of about 3000 to about 4000, said glycidyl ester being present in said copolymer from at least about 12 percent by weight to no more than about 20 percent by weight.

Claim 18

A powder coating composition in accordance with claim 13 wherein said monoethylenically unsaturated monomers consist essentially of monofunctional, alpha-beta olefinically unsaturated monomers.

Claim 19

A powder coating composition in accordance with claim 16 wherein said monofunctional, alpha-beta olefinically unsaturated monomers consist essentially of monofunctional, alpha-beta olefinically unsaturated monomers.

Claim 20

A powder coating composition in accordance with claim 16 wherein said monofunctional, alpha-beta olefinically unsaturated monomers are acrylates.

Claim 21

A powder coating composition in accordance with claim 18 wherein said acrylates consist essentially of esters of C 1 - C 8 monohydric alcohols and acrylic or methacrylic acid.

Claim 22

A powder coating composition in accordance with claim 16 wherein said monofunctional, alpha-beta olefinically unsaturated monomers consist essentially of a mixture of acrylates and vinyl hydrocarbons, said acrylates comprising greater than 50 weight percent of the monomer content of the copolymer.

Claim 23

A powder coating composition in accordance with claim 20 wherein said vinyl hydrocarbons are selected from the group consisting of styrene, alpha-methyl styrene, vinyl toluene, t-butyl styrene and chlorostyrene.

Claim 24

A powder coating composition in accordance with claim 13 wherein said copolymer includes up to 35 weight percent of modifying monomers selected from the group consisting of vinyl chloride, acrylonitrile, methacrylonitrile and vinyl acetate.