Synthesis and electrorhelogy of multi-walled carbon nanotube/polyaniline nanoparticles

Nanoparticles with multi-walled carbon nanotube (MWNT) and polyaniline (PANI) were synthesized via an oxidative dispersion polymerization using poly(vinyl alcohol) (PVA) as a polymeric stabilizer and HCl as a dopant. Prior to the synthesis, the MWNT was treated with strong acidic solutions via a reflux process to eliminate impurities including metallic catalysts. These MWNT/PANI nanoparticles were well dispersed in water because the hydrophilic PVA was stably adsorbed onto the nanopartcle surface. These MWNT/PANI nanoparticles were used as suspended particles for an electrorheological (ER) suspension, and the rheological properties for this ER fluid including yield stress and shear viscosity under several different applied electric field strengths were examined via a rotational rheometer equipped with a high DC voltage generator.