Properties of organic-inorganic composite materials prepared from acrylic resin emulsions and colloidal silicas

To design an organic-inorganic composite material with colloidal silica as the inorganic component, an acrylic resin emulsion and an organic silane hybridized acrylic resin emulsion were prepared by emulsion polymerization. The organic-inorganic composite films were prepared by blending the emulsion and the colloidal silica. The contact angles for water, gloss at 60 degrees, and the transparencies of those films were measured. The dispersion state of colloidal silica in films was observed with a scanning electron microscope (SEM) and a transmission electron microscope (TEM). From these results, the contact angle for water of the organic-inorganic composite film obtained from the silane hybridized acrylic resin emulsion was lower than that of the organic-inorganic composite film obtained from an acrylic resin emulsion. The contact angles for water in organic-inorganic composite films with colloidal silicas were lower than those of the films without the colloidal silicas. The films prepared from silane hybridized acrylic resin emulsion composites with colloidal silicas of less than 100 nm were more hydrophilic. SEM and TEM observations demonstrated that some aggregations of the small colloidal particle silica were densely dispersed on the film surface. (c) 2006 Wiley Periodicals, Inc.