Synthesis of conductive adhesives based on epoxy resin and polyaniline.DBSA using the in situ polymerization and physical mixing procedures

Electrically conductive adhesives based on epoxy-anhydride system containing polyaniline (PAni) doped with dodecylbenzenesulfonic acid (DBSA) have been successfully developed and characterized. The blends were prepared by physical mixing and by in situ polymerization of aniline within epoxy matrix. The in situ polymerization procedure contributes for the formation of a conducting pathway with lower amount of PAni.DBSA. A conductivity as low as 10−3 S cm−1 with 12 wt% of PAni and excellent adhesion properties were achieved with these systems. The microstructure of the conductive adhesives was studied by means of scanning electron microscopy (SEM). In the case of blends prepared by in situ polymerization, PAni.DBSA is dispersed within the epoxy matrix in the form of microtubules. Dielectrical properties as a function of frequency and temperature have also indicated a great interaction between polyaniline and epoxy matrix by in situ polymerization procedure.