Interface and bulk properties in films of phase separated dispersion particles

Abstract

Structured latex particles are of high interest as tailor made dispersion binders to meet contradictory requirements in different fields of applications. Aqueous dispersions, e.g. used as binders in solvent-free, low pigmented paint formulations, have to cope with the challenge to guarantee an excellent film forming ability at room temperature as well as a low tack. In this work, the synthesis and characterizations of hemisphere-like particles with different chemical constitutions are described. The single particles were placed onto various types of substrates. The particle–surface interface was then investigated by atomic force microscopy (AFM). Characteristic differences were found as a function of the polarity of both, polymer and substrate. Including these findings, AFM was used to determine the impact of the interface structure on the bulk properties of the final dispersion films. The results are compared to computer simulations of the packing of the particulate materials. A correlation of microscopic interface structure to macroscopic application properties of the corresponding dispersion films is presented. The results are compared to sets of blends with identical chemical composition and equivalent volume fraction and the corresponding statistical copolymers.