Synthesis and electrical properties of polymer composites with polyaniline nanoparticles

Nano-sized polyaniline (PANI) particles dispersed in aqueous solution were prepared using both poly(vinyl alcohol) (PVA) and poly(styrene sulfonic acid) (PSSA) as polymeric stabilizers. Size of the spherical PANI particle synthesized using PVA with a HCl dopant (PANI-HCl/PVA) was about 150 nm in diameter, and that with PSSA (PANI-PSSA) was about 50 nm, with a uniform size distribution. Doping level of the PANT-PSSA measured by UV-visible spectrometer was higher than that of PANI-HCl/PVA. The PVA based composite films using both PANI-HCl (PANI-HCl/PVA) and PANI-PSSA (PANI-PSSA/PVA) were prepared by a casting method for different PANI content and their electrical conductivities were measured. A percolation threshold of PANI concentration for conductivity of composite was found only around 10 wt.% of PANI for the PANI-PSSA/PVA, and furthermore, the PANI-PSSA/PVA became more conductive above the threshold point than PANI-HCl/PVA. (C) 2003 Elsevier B.V. All rights reserved.