Novel synthesis of silica/polypyrrole hybrid nanocomposites via microemulsion polymerization with a vapor monomer feeding system

Silica/polypyrrole hybrid nanoparticles were synthesized by microemulsion polymerization using a vapor monomer feeding system. In contrast to the traditional monomer feeding methods of microemulsion polymerization, this study examined the monomer feeding as a vapor phase. The silica modified with 3-(trimethoxysilyl)propyl methacrylate had a hydrophobic surface was used as template. Polymerization of the pyrrole monomers occurred at the surface of the modified silica. By controlling the vapor feeding speed, the pyrrole monomer could be dispersed in the reaction system quite well. The modification of silica and the formation of silica/polypyrrole nanoparticles were characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis. The silica/polypyrrole hybrid morphology was confirmed by transmission electron microscopy and scanning electron microscopy. Through a comparison with the nanoparticles made by traditional microemulsion polymerization, uniform and smaller nanoparticles of the silica/polypyrrole hybrid nanocomposite were prepared using a lower surfactant content. The size of the silica/polypyrrole nanocomposites decreased with increasing surfactant content and decreasing pyrrole monomer content.