Topological morphology of methylsilsesquioxane derivatives

A change in the morphological topology of particles of methylsilsesquioxane derivatives is observed with a change in the silicone monomer formulation. The particles change from a spherical shape to a hollow hemispherical shap e with an increase in the content of silica-forming monomers in methylsilse squioxane-forming monomers, whereas the spherical shape does not change wit h the addition of dimethyl silicone-forming monomers to methylsilsesquioxan e-forming monomers. The intermediate shape is a sphere surrounded by a wrin kly surface, like a soccer ball, and the particle finally becomes a hollow hemisphere. These phenomena were examined by FT-IR, Si-29 CP/MAS NMR (solid -state), and XPS spectra from the perspective of internal steric stress due to tetra- or trifunctional units in the particle core.