Preparation of mesoporous benzene-silica nanoparticles

Nanoparticles of periodic mesoporous organosilica (PMO) with benzene bridging groups were prepared using a 1,4-bis(triethoxysilyl)benzene organosilica precursor and mixed surfactant templates composed of a poly(ethylene oxide)-poly(dl-lactic acid-co-glycolic acid)-poly(ethylene oxide) (PEO-PLGA-PEO) triblock copolymer and a fluorocarbon surfactant under acidic conditions. Mesoporous organosilica particles clearly exhibited a nanoscale diameter of 50-1000 nm by scanning electron microscopy. Moreover, these particles possessed a mesostructure with uniform pores in the range of 6.3-6.6 nm and core-shell type spherical morphology, which were confirmed by Synchrotron small angle X-ray scattering, transmission electron microscopy, and nitrogen adsorption analysis. Benzene bridging groups linked covalently to Si atoms were analyzed by solid state ¹³C- and ²⁹Si MAS NMR.