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Abstract: In this work, mesoporous silica (MCM-41) was modified by triethanolamine (TEA) by a wet impregnation method. The structure and morphology of modified MCM-41 particles were characterized by X-ray diffraction, N2 adsorption/desorption, Fourier-transform infrared spectra, scanning electron microscopy, particle size analyzer and thermogravimetric analysis. The results show that the interior channels of MCM-41 are modified by TEA without destroying its mesoporous structure. Further, pure MCM-41and TEA-modified particles were adopted as dispersed phase in silicone oil for electrorheological (ER) investigation. The TEA-MCM-41 (modified with 7wt.% TEA)-based ER fluid with a volume fraction of 5% exhibits stronger ER activity than pure MCM-41 fluid. The possible mechanism related to dielectric properties is also provided. [Copyright &y& Elsevier]

Abstract: A new nanocomposite, semiconducting polypyrrole (PPy) confined in mesoporous silica (MCM-41) has been synthesized. PPy was formed in the pores of MCM-41 by adsorption of pyrrole gas and subsequent oxidative polymerization with FeCl3·6H2O. Different techniques were used to characterize the nanocomposite formation. X-ray diffraction (XRD) and N2 adsorption/desorption analysis show that the nanocomposite possesses mesoporous structure, and the residual pore volume of nanocomposite is significantly lower than that of pure empty MCM-41. FTIR spectra, high resolution transmission electron micrographs and electrical conductivity measurements confirmed the presence of polypyrrole inside pore channels of the host, and thermogravimetric analysis proved confinement effect in the channel system. [Copyright &y& Elsevier]