Preferential distribution of polyaniline in different phases of acrylate triblock copolymer

Polyaniline (PAni) nanorod was synthesized through electrochemical polymerization method from aniline sulphate in aqueous medium. Nano-composite of PAni with acrylate block copolymer (BCP) was prepared by dispersing PAni at 2% and 4% loading into ABA type poly(methyl methacrylate-b-butyl acrylate-b-methyl methacrylate) (PMMA-b-PBA-b-PMMA) triblock copolymer via solution casting method. Morphological studies prove that at lower loading PAni first goes to PMMA phase leading to increase in surface roughness, followed by PBA phase at increased loading leading to decrease in surface roughness due to increase in homogeneity of distribution of polyaniline in the matrix. AC resistivity decreases with polyaniline loading. Preferential addition to PMMA phase at 2% loading shows the lowest resistivity whereas dielectric constant is the highest in 4% loading. Addition of PAni, even at low loading increases thermal stability of the copolymer matrix. Thermal degradation characteristics of the composites show well correlation with the distribution characteristics of PAni in copolymer matrix.