Atomic Force Microscopy Study of Organic−Inorganic Hybrid Materials

Abstract

A series of monolithic poly[methyl methacrylate- co -3-(trimethoxysilyl)propyl methacrylate]−silica hybrid materials have been prepared via the sol−gel reactions. The fracture surfaces of the materials were systematically examined with atomic force microscopy (AFM) as a function of the silica content from ∼23 to 100 vol %. For the transparent materials, the AFM image of the sample at a low silica content of 23 vol % is very smooth and essentially featureless while those at higher silica contents show relatively greater surface roughness and development of domains of various shapes and sizes. In sharp contrast, the optically translucent and phase-separated samples exhibit significantly higher surface roughness and larger domain size than all the transparent hybrid materials, suggesting that the transparent materials might have little or no organic−inorganic phase separation.