Polyurethane macromers—new building blocks for acrylic hybrid emulsions with outstanding performance

Abstract

Emulsion polymerization is an efficient process to produce waterborne binders. It has been observed that films prepared from traditional latices do not show high performance especially concerning humidity and stone chip resistance. Polymeric emulsifiers are promising alternatives to low molecular weight surfactants. Polyurethanes are an interesting polymer class. The structure of the polymer backbone can be varied in a wide range by using different building blocks. The synthesis of copolymerizable polyurethanes, which have an amphiphilic structure similar to traditional surfactants, and their use in aqueous polymerization is discussed in detail. This process leads to polymer emulsions with structured particle morphology. The resulting films show outstanding properties. The polyurethane–polyacrylic dispersions can be used as binders for high performance waterborne coating formulations.