Probing the assembly of highly vinyl-functionalized periodic mesoporous organosilica materials with crystal-like frameworks

摘要

Vinyl-functionalized periodic mesoporous organosilica materials (PMOs) with a crystal-like wall structure were synthesized, for the first time, by direct co-condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) and triethoxyvinylsilane (TEVS). The synthesis approach led to high loading of vinyl functional groups and controlled regular morphologies. The resultant materials with different TEVS contents (up to 60 molar percentage) consisted of well-ordered mesopores (2.82-3.29 nm) with molecular-scale periodicity (7.6 A) in the walls, so that the high thermal stability of phenylene-bridged organosilica and versatile functionality of vinyl groups are combined. By exploring the influence of TEVS loading and the second monomer, tetraethoxysilane (TEOS), on the molecular-scale regularities, the rule of synergetic assembling of functional monosilylated TEVS and bissilylated BTEB was revealed. That is, the PMOs framework was built up only by BTEB, while TEVS was always terminally bonded to the channels surface.