Electrorheological properties of suspensions of polypyrrole ribbon particles in silicone oil

Abstract

A new polypyrrole (PPy) ribbon particles structure has been synthesized by solution chemistry method (oxidative polymerization) in the presence of surfactant cetyltrimethylammonium bromide (CTAB) with oxidizing agent ammonium persulfate (APS). The resulted polymer was treated with ammonium hydroxide (NH4OH) several times to obtain different sample conductivity. PPy morphology was characterized by SEM. The suspensions were prepared by dispersing PPy with different conductivities in silicone oil. The electrorheological effect (ER) for the suspensions was examined under various electric fields using a rotational rheometer. It was found that suspension of only 3 wt. % of PPy ribbon particles showed large ER effect providing yield stress of 256 Pa at 3 kV.mm(-1).