Facile synthesis of casein-based silica hybrid nano-composite for coatings: Effects of silane coupling agent

Silane coupling agents are recognized as efficient coupling agents extensively used in composites and adhesive formulations. In this paper, casein-based silica nano-composite latex for coatings was prepared via double-in situ method stabilized by methyl propyl trimethoxy silane (KH570) - a kind of silane coupling agent. The latex was mainly characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermogravimetry (TGA). Effects of KH570 on the structure and performance of the latex and film, as well as the application performance were discussed systematically. The results showed that the presence of KH570 increased the silica-shell uniformity due to the improvement of the compatibility between the organism and inorganism. Existence of KH570 could endow the hybrid film with enhanced mechanical strength, water resistance and heat resistance. The as-prepared composite may also give finished leather with preferred wet/dry rub resistance, water resistance and tensile strength. Latex particle formation mechanism was proposed accordingly. (C) 2015 Elsevier B.V. All rights reserved.