Improved Electrorheological Effect in Polyaniline Nanocomposite Suspensions

Abstract

We prepared polyaniline (PANI)/clay composites that are composed of both PANI–clay nanocomposite particles and pure PANI particles. The PANI–clay nanocomposite particles were made during the polymerization process, wherein PANI particles are attached on the surface of exfoliated clay particles modified by an aminosilane group. The PANI/clay composites were used as electrorheological fluids (ERFs) by dispersing them in silicon oil. The PANI–clay nanocomposite particles, which can form columnar structure under an electric field, strongly enhance the mechanical rigidity of the suspensions. The maximum yield stress of the PANI/clay composite suspensions (15 wt% in silicon oil) was 1.6 kPa at 3 kV/mm, while that of pure PANI was 300 Pa at the same electric field. A mechanism to explain the yield behaviors of the PANI-based nanocomposite suspensions is proposed.