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Abstract: In this study, a new mesoporous material with semiconducting polypyrrole (PPy) encapsulated in the channels of mesoporous silica (MCM-41) was synthesized and used as dispersed phase for electrorheological (ER) fluids. Rheological and dielectric properties of PPy-MCM-41 based suspensions were investigated with the conclusion that PPy-MCM-41 fluid exhibits better ER behavior than that without PPy. The static yield stress of 10wt.% PPy-MCM-41 fluid as a function of applied electric field strength shows two different slopes depending on the electric field strength. Furthermore, the dielectric spectra indicate that encapsulated PPy increases the interfacial polarizability of mesoporous material and induces a higher ER effect. [Copyright &y& Elsevier]

Abstract: A new nanocomposite with conducting polypyrrole (PPy) confined in ordered mesoporous silica SBA-15 channels has been synthesized by an in situ polymerization technique. The resulting material was characterized by X-ray diffraction (XRD), N2 adsorption/desorption, high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectra (FT-IR) and thermogravimetric analysis (TGA). The results show that PPy is formed in the channels instead of coating the outer surface of SBA-15 and nanocomposite possesses well-ordered hexagonal structure. Further, nanocomposite particles were used as dispersed phase in silicone oil for electrorheological (ER) investigation. Suspension of PPy–SBA-15 displays notable ER characteristics under external electric fields. [Copyright &y& Elsevier]

Abstract: In this work, polypyrrole/nano-Y2O3 conducting composite was synthesized by chemical oxidative polymerization. The composite was characterized using transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra, UV–vis absorption spectra, X-ray photoelectron spectroscopy and electrical conductivity measurements. The results indicate that Y2O3 nanoparticles are almost enwrapped by polypyrrole. The addition of Y2O3 nanoparticles results in changes in the surface structure and conductivity of the composite. Thermogravimetric analysis shows that composite has better thermal stability than that of pure polypyrrole. [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]