Abstract: A binder for a coating composition is obtainable as the reaction product of a carboxyl-terminated fatty acid ester with an ethylenically unsaturated carboxylic acid and an ethylenically unsaturated carboxylic acid ester. The carboxylic fatty acid ester is produced by reaction of an autoxidisable fatty acid and a polyol, with modification to introduce at least one terminal carboxyl group. The reaction is optionally effected in an organic solvent which is substantially removed at the end. The material is neutralized with a base to render it water-soluble. Thixotropy can be endowed by an amine/(poly)isocyanate final reaction stage to prior neutralization.

Abstract: Curable compositions for making fibre-reinforcement structural composites such as GRP comprise an unsaturated polyester resin base, a co-polymerizable monomer and preferably, one or more performance-enhancing additives. Thixotropy is endowed by 5% by weight or less of an organic amide.