Synthesis and characterization of ethylene vinyl-acetate/polyaniline blends prepared by emulsion polymerization technique

A series of ethylene vinyl acetate-polyaniline (98/02, 95/05, 93/07...... 50/50) (EVA-PAni) blends were prepared by the emulsion polymerization technique and made into sheets by the compression molding at 150degreesC. These sheets were characterized by electrical, physico-mechanical, thermal, X-ray and morphological studies. All electrical properties of EVA-(PAni)(TSA) blends increased with an increase in PAni content. The conductivity, dielectric constant and tan 8 values increased from 1.34 X 10(-14) to 2.89 x 10(-2) S/cm, from 2.113 to 19.845, from 0.094 to 4.789. Tensile strength increased with an increase in PAni content up to 7% and drastically decreased above 15%, while the percentage elongation at break decreased with an increase in PAni content. TGA studies revealed that the thermal stability of PAni improved after blending with EVA. EVA-PAni blends were found stable up to 110degreesC. X-ray diffractograms of EVA-PAni blend showed an intense peak at 26degrees (2theta), reflecting the influence of EVA crystallinity. Scanning electron micrographs confirmed the two-phase morphology of the system.