Alkoxysilane functional acrylic latexes: influence of copolymer composition on self-curing behavior and film properties

Reactive latexes based on acrylic polymers with trimethoxysilyl groups in the side chain were prepared by semi-continuous emulsion copolymerization. The properties of the latex film related to the polymer network structure and their evolution upon thermal curing were studied as a function of the content of the reactive comonomer, trimethoxysilylpropyl methacrylate (TSPMA), ranging between 8 and 25 wt-%. In particular, the sensitivity to both organic solvent (chloroform) and water and the thermomechanical properties were investigated by swelling experiments and dynamic-mechanical analysis (DMA). The results are interpreted in terms of a transition from uniform to microheterogeneous crosslinking regime, possibly as the result of formation of polyorganosilsesquioxane-like (POSS) crosslinking domains at higher TSPMA content.