Water-borne Polyester Coatings By Miniemulsion Polymerization

Abstract

A distinctive graft copolymer is made by dissolving an unsaturated polyester resin in various vinyl monomers (methyl methacrylate, styrene, etc.). The monomer/unsaturated polyester solution is then miniemulsion polymerized to form a latex consisting of submicron particles of polymer with the polyester grafted onto the polymer backbone. The latex can be applied to a substrate, which on drying forms a polymeric film with good film properties. The latex can be used in a latex paint formulation in place of an acrylate, acetate or styrene-divinyl benzene latex. In this way it is possible to produce water-borne unsaturated polyester coatings which combine the film hardness properties of an unsaturated polyester coating with easy application and cleanup. The coating will beneficially lack organic solvent exposure of typical polyester coatings.