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Mixtures of methyl-and phenyltrichlorosilanes have been hydrolyzed to obtain cross-linked polysiloxanes, often referred to as polysilsesquioxanes. Glassy or amorphous materials are obtained, depending on the reaction conditions used. Infrared spectroscopy, scanning electron microscopy, and gas chromatography have been employed to study the surface characteristics of these materials. The infusible solids that are obtained are thermally stable up to 400 °C. Surface areas for the materials range from 0.02 to 5 m2/g, depending on the reaction conditions. Swelling experiments show that the materials are very tightly cross-linked networks. The soft materials having surface areas around 5-10 m2/g are suitable as adsorbents for gas-solid chromatography.

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The fracture behavior of three high-impact polystyrene (HIPS) materials has been investigated using constant load at 1 /2 h interval tests of margarine-exposed compact tension fracture mechanics specimens. Scanning electron microscopy has also been done on the fracture surfaces to correlate the micromechanics of fracture to the fracture test results. The results indicate that the proposed tests provide a useful approach to study the environmental fracture resistance (EFR) of HIPS under the influence of a n aggressive environment. It was found that the EFR of HIPS under margarine, with comparable rubber content, improves with decreasing rubber particle size and increasing molecular weight.