Preparation of porous aminopropylsilsesquioxane by a nonhydrolytic sol-gel method in ionic liquid solvent

The synthesis of porous aminopropylsilsesquioxane (APSS) has been achieved with 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+PF6-) ionic liquid (IL) as a template solvent by a nonhydrolytic sol-gel method of 3-aminopropyltrimethoxysilane under mild temperature. By the alteration of the amount of IL or the catalyst, the gels with various specific surface areas ranged from similar to600 to similar to1500 m(2) g(-1) were obtained after the remove of IL by calcination, and their N-2 sorption isotherms were typical IV-like isotherms with H2 hysteresis. The average Battett-Jouner-Halenda pore diameters ranged from 3.2 to 5.6 nm. The results demonstrated that BMIM+PF6- was physically embodied in the silsesquioxane bulk instead of the chemical bonding. Silsesquioxane has promise in catalysis, biosensors, etc. This work would also provide a way for us to prepare a wide variety of materials by using IL as a template solvent.