AQUEOUS COATING COMPOSITIONS CONTAINING ACETOACETYL-FUNCTIONAL POLYMERS, COATINGS, AND METHODS
Aqueous coating compositions that include polymers having one or more of the following acetoacetyl-functional groups: wherein R 1 is a C1 to C22 alkylene group and R 2 is a C1 to C22 alkyl group.
1 . A coating composition comprising:
water;
a polymer comprising one or more acetoacetyl functional groups of the formula:
wherein R 1 is a C1 to C22 alkylene group and R 2 is a C1 to C22 alkyl group; and
a (meth)acrylate functional compound distinct from the polymer comprising the one or more acetoacetyl functional groups; wherein the (meth)acrylate functional compound is present in an amount of at least 5 wt-%, based on the combined weight of the (meth)acrylate functional compound and the acetoacetyl-functional polymer;
wherein the acetoacetyl-functional polymer comprises an acetoacetyl-functional latex polymer prepared from ethylenically unsaturated monomers, and wherein the latex polymer is stabilized with an alkali-soluble polymer.
2 . The coating composition of claim 1 comprising no more than 10 wt-% volatile organic compounds, based on the total weight of the composition.
3 . The coating composition of claim 1 wherein the (meth)acrylate functional compound is a monomer, oligomer, polymer, or mixture thereof.
4 . The coating composition of claim 1 wherein the (meth)acrylate functional compound is a multifunctional monomer.
5 . The coating composition of claim 4 wherein the (meth)acrylate-functional monomer selected from the group consisting of isobornyl (meth)acrylate, isodecyl (meth)acrylate, phenoxyethyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethoxylate tri(meth)acrylate, tripropylene glycol di(meth)acrylate, hexanediol di(meth)acrylate, tetrahydrofurfuryl (meth)acrylate, beta-carboxyethyl (meth)acrylate, bisphenol A ethoxylate di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, propoxylated neopentyl glycol di(meth)acrylate, di-(trimethyolpropane tetra (meth)acrylate), pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and mixtures thereof.
6 . The coating composition of claim 1 wherein the acetoacetyl-functional polymer comprises an acetoacetyl-functional polyurethane, epoxy, polyamide, chlorinated polyolefin, acrylic, oil-modified polymer, polyester, or mixtures or copolymers thereof.
7 . The coating composition of claim 1 wherein the acetoacetyl-functional polymer comprises an acetoacetyl-functional latex polymer prepared from ethylenically unsaturated monomers.
8 . The coating composition of claim 7 wherein the acetoacetyl-functional latex polymer comprises latex particles having an average particle size of less than 75 nm.
9 . The coating composition of claim 7 wherein the ethylenically unsaturated monomers used in preparing the acetoacetyl-functional latex polymer are selected from the group consisting of 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, hydroxybutyl acrylate, hydroxybutyl methacrylate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidylether, acrylamide, methylacrylamide, styrene, α-methyl styrene, vinyl toluene, vinyl acetate, vinyl propionate, allyl methacrylate, and mixtures thereof.
10 . The coating composition of claim 1 wherein the acetoacetyl-functional polymer is present in an amount of at least 30 wt-% and no more than 95 wt-%, based on the combined weight of the (meth)acrylate functional compound and the acetoacetyl-functional polymer.
11 . The coating composition of claim 1 wherein the (meth)acrylate functional compound is present in an amount of no more than 70 wt-%, based on the combined weight of the (meth)acrylate functional compound and the acetoacetyl-functional polymer.
12 . The coating composition of claim 1 wherein the acetoacetyl functional group is incorporated into the polymer using 2-(acetoacetoxy) ethyl methacrylate, t-butyl acetoacetate, diketene, or combinations thereof.
13 . The coating composition of claim 1 further comprising a free-radical initiator.
14 . The coating composition of claim 13 wherein the free-radical initiator comprises a photoinitiator, a thermal initiator, a catalyst for auto-oxidative cure, or combinations thereof.
15 . The coating composition of claim 14 wherein the free radical initiator is a photoinitiator.
16 . The coating composition of claim 15 wherein the photoinitiator comprises benzophenone, 4-methylbenzophenone, benzoyl benzoate, phenylacetophenones, 2,2-dimethoxy-2-phenylacetophenone, alpha,alpha-diethoxyacetophenone, hydroxycyclo-hexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentyl phosphine oxide, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, or combinations thereof.
17 . The coating composition of claim 15 wherein the photoinitiator is a hydrogen abstraction-type photoinitiator.
18 . The coating composition of claim 17 wherein the hydrogen abstraction-type photoinitiator is benzophenone or 4-methylbenzophenone.
19 . The coating composition of claim 18 which is at least partially curable by ultraviolet or visible light.
20 . A method of coating a substrate, the method comprising applying the coating composition of claim 1 to a substrate and allowing the coating composition to harden.
21 - 36 . (canceled)