Electrically conductive, melt-processed polyaniline/EVA blends

Mechanical blends of ethylene-vinyl acetate copolymer and polyaniline doped with dodecyl benzene sulfonic acid (PAni-DBSA) were prepared in a two-roll mill at 50 degreesC and in a Haake internal mixer at 150 degreesC. The effects of the blend composition and processing conditions on the electrical conductivity and mechanical properties were investigated. These blends exhibited high levels of electrical conductivity at a small amount of PAni complex. Blends prepared in a two-roll mill displayed conductivity values as high as 1 S/cm and a higher protonation degree than the pure PAni-DBSA, as indicated by X-ray photoelectron spectroscopy. Two different insulator-conductor transition points were observed in these blends. The mechanical performance decreased as the amount of PAni-DBSA increased, indicating blend incompatibility and a plasticizing effect of the DBSA. The morphology of the blends were studied by scanning electron microscopy. (C) 2001 John Wiley & Sons, Inc.