A family of three-dimensional cubic (Pm3n) periodic mesoporous silsequioxanes (PMS) with alkylene bridging groups was prepared by surfactant templating. PMS materials with methylene-, ethylene-, hexylene-, and octylene-bridging groups were synthesized from bis(triethoxysilyl)methane, 1, 2-bis(triethoxysilyl)ethane, 1, 6-bis(triethoxysilyl)hexane and 1, 8-bis(triethoxysilyl)octane, respectively, in the presence of the surfactant, Brij 56, under acidic conditions. Highly ordered, cubic (Pm3n) mesostructures in all of the alkylene-bridged PMS samples were confirmed by small angle X-ray diffraction and transmission electron microscopy. The PMS materials were very porous with surface areas over 800 m2g-1 and narrow distributions of pores between 2 and 4 nm in diameter. Length of the bridging groups appeared to have little effect on the structure and porosity of the PMS materials, but the contact angle increased dramatically with increasing bridging group length. The high surface area, isotropic pore structure and variable hydrocarbon content should make the alkylene bridged PMS materials promising candidates for organic pollutant adsorbents from water or air.
- Contact angle
- Ethylene-bridged polysilsesquioxane
- Periodic mesoporous materials
ASJC Scopus subject areas
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering