Synthesis and electrorheological properties of polyaniline‐coated barium titanate composite particles

Abstract

Abstract Polyaniline‐coated barium titanate composite particles were synthesized by surface grafting polymerization, in which five silane coupling agents with different terminal groups were used. The structure of composite particles was characterized by SEM, XRD, FTIR, and TGA, and the electrorheological properties were tested by rotational rheometer. The results show that polyaniline was coated on the surface of barium titanate particles to form the shell‐core structure. The yield stress of the electrorheological fluids based on polyaniline‐coated barium titanate composite particles is higher than that of polyaniline and barium titanate. Compared with PANI‐based electrorheological fluids (ERFs), the composite particles‐based ERFs have lower field‐off viscosity due to the molecular interaction. The yield stress of the ERFs, as well as density of the composite particles, was affected by the groups at terminal of silane coupling agents. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008