Silsesquioxanes as Synthetic Platforms. 3. Photocurable, Liquid Epoxides as Inorganic/Organic Hybrid Precursors

Platinum-catalyzed hydrosilylation of allyl glycidyl ether (AGE) with octahydridosilsesquioxane ((HSiO1.5)8, T8H) and octakis(dimethylsiloxy)silsesquioxane ((HMe2SiOSiO1.5)8, Q8M8H) provides access to tetra- and octaepoxy-functionalized cubic silsesquioxanes (cubes). The resulting epoxy cubes offer “masked” silica contents of up to 65 wt %, are soluble in common solvents, and are viscous liquids at room temperature, making them attractive for coating and nanocomposite applications. They polymerize on exposure to UV light in the presence of a cationic photoinitiator to produce insoluble, hybrid nanocomposites.