Preparation and Characterization of Silica/Polypyrrole Core-Shell Colloidal Particles in the Presence of Ethanol as the Cosolvent

The silica/polypyrrole core-shell composites were fabricated by in situ chemical polymerization of pyrrole monomer on the surface of the silica spheres. Silica sol particles with narrow size distributions were prepared by hydrolysis of tetraethoxysilane with solgel method. Polypyrrole shell was obtained by chemical polymerization of pyrrole monomer on the surface of the silica spheres in the water-ethanol mixture. It can be seen from the experiment, with the adding of small amount of ethanol cosolvent to the aqueous reaction solution, a uniform coating of polypyrrole appeared on the surface of silica. The core-shell morphology of composite particles prepared with variation ethanol adding amount was analyzed by TEM. Meanwhile, the conductivity of the core-shell composite is found to be enhanced apparently compared with those prepared from pure aqueous system. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 3270-3274, 2012