Abstract: The present invention provides reactive aqueous or solvent borne compositions comprising one or more low-temperature curing alkylether functional aminoplast resins having an average degree of polymerization of from 1.0 to 2.0, preferably alkylether group containing melamines, one or more hydroxyl group containing resins or polymers, such as acrylics and polyesters, one or more unblocked acid catalysts each having a pKa of 0.25 to 1.0, such as organic sulfonic acids, and one or more volatile amines, e.g. N-dipropylamine, that have a relative evaporation rate (RER) of 50-500, wherein, RER equals (p)(M)/11.6, with p being the vapor pressure of the amine in mm Hg and M being the molecular weight of the amine. The compositions cure at from 60° C. to 135° C., e.g. below 105° C., to form durable coatings suitable for plastic substrates, such as automotive plastics.

Abstract: The present invention provides one-component compositions which comprise one or more hydroxyl functional acrylic resin having a glass transition temperature (Tg) of from ?100° C. to ?10° C. and one or more dialkyl dicarboxylic acid ester endcapped polyisocyanate crosslinker, such as the isocyanurate of isophorone diisocyanate (IPDI), and flexible, environmental etch resistant coatings made therefrom. The acrylic resins comprise the polymerized reaction product of one or more flexibility conferring monomers, e.g. butyl acrylate, and provide the coating with its flexibility. The one or more dialkyl dicarboxylic acid ester endcapped polyisocyanate and the hydroxyl groups in the one or more acrylic resins react to cure at lower temperatures than current one-component blocked isocyanate coatings. Alternatively, one-component coating compositions consists essentially of one or more rigid hydroxyl functional acrylic resin and one or more dialkyl dicarboxylic acid ester endcapped aliphatic polyisocyanates.