Synthesis and electrorheological characteristics of microencapsulated conducting polymer

The microencapsulation method is adopted as a substitute for doping and dedoping procedures of polyaniline (PANI) in order to improve particle properties, such as electrical conductivity and dielectric constant and its density mismatch with a suspending liquid medium. The pH of the PANI has been controlled to adjust the electrical conductivity and to enhance electrorheological (ER) efficiency. Microencapsulation of PANI with low pH as the core material was prepared by in situ polymerization of melamine-formaldehyde resins, as the shell material acts as an insulator between PANI particles, using two different emulsifiers. We investigated the effect of the imposed electric field strengths on the yield stress of ER fluid, and also analyzed the dielectric relaxation process of the microencapsulated PANI (MCPA) by the dielectric spectra and Cole-Cole plots.