Preparation and electrorheological characteristics of PANI/MWNT nanocomposite

We prepared polyaniline (PANI) /multi-walled carbon nanotube (MWNT) nanocomposites of both PANI pierced MWNT nanocomposites synthesized using polyvinyl alcohol) as a polymeric stabilizer and PANI/MWNT nanocables via an in-situ oxidative polymerization directed by a cationic surfactant of cetyltrimethylammonium bromide (CTAB). In addition to chemical analysis of the products, the formation of nanocomposite nanocable and their morphology in which the MWNTs were entirely encapsulated by amorphous PANI, were confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Electrorheological (ER) fluids were prepared by dispersing both of these synthesized MWNT/PANI nanocomposites in insulating silicone oil and their ER properties were investigated by controlling applied DC electric field strengths. The synthesized nanocomposite particles have enhanced interparticle interactions, and the shear stresses increase with the electric field strength for a broad range of shear rate. Among three different constitutive equations adopted, the Cho-Choi-Jhon model was found to fit the flow curves quite well.