COMPUTER-AIDED SELECTION OF A POLYMER MATRIX FOR POLYANILINE CONDUCTIVE BLENDS

The selection of a polymer matrix for a conductive blend with polyanil ine and para-toluene sulfonic acid (PANI-pTSA) was performed using mol ecular simulation techniques, both a fast quantitative structure-prope rties relationship method as a first screening phase followed by atomi stic simulation. Using the atomistic simulation method, the solubility parameters and the hear of mixing of each blend were calculated to en able the determination of compatible matrices in blends with PANI-pTSA , which was validated by experimental scanning electron microscopy fra ctographs. Based on such calculations, polycaprolactone (PCL)/PANI-pTS A phase diagrams were estimated, showing slight miscibility of polydis persed PANI in PCL, particularly the short chains fraction, at the ele vated melt processing temperature. It was suggested that this partial miscibility at the elevated temperature might lead to a conductive net work morphology of PANI in PCL at room temperature, because of phase s eparation and precipitation of soluble PANI molecules, upon cooling an d solidification of the melt. (C) 1998 John Wiley & Sons, Ltd.