Structure of Composite Films Containing Polyaniline Studied by DSC

A structural study of conductive composite films consisting of ethylene-co-vinylacetate (EVA) copolymer, polyaniline (PANI) and dodecylbenzenesulfonic acid (DBSA), a part of which being complexed with PANI, was performed by using differential scanning calorimetry (DSC) and presented for the first time. An additional crystalline phase is formed during the film formation by thickening EVA chain-folded lamellae with participation of‘free’ DBSA molecules at lower net PANI content (up to 5 mass%) and of both ‘free’ and complexed DBSA molecules (up to 7.5 mass%). At higher PANI content PANI-DBSA complex starts to form its own crystals and at 17.5 mass% of PANI mixed crystals of EVA with ‘free’ DBSA alkyl chains are preferably formed. It is also found that the Fox' equation correlating the glass transition temperature of a miscible blend system with its composition can be actually used in estimating the miscibility of EVA/PANI blends no matter the presence of DBSA. This revised version was published online in August 2006 with corrections to the Cover Date.