Effect of the Polyamide Type on the Physical Properties of Layered Polyaniline Composite Films

The present work deals with the investigation of the dielectric properties of layered polyamide/polyaniline films and their correlation to the microstructure. A thin polyaniline (PANI) layer was polymerized in the subsurface of polyamide films. The dielectric relaxation spectroscopy was used to compare the electrical behaviour of flexible polyamide 6 (PA6) and polyamide 12 (PA12) surfaces loaded with PANI nanoparticles, while the roughness was investigated by the contact angle technique. Relatively high dielectric constants were recorded for PA12/PANI films compared to PA6/PANI ones due to the hydrophobic nature of the PA12 matrix. This also explained the wettability enhancement observed for PA12/PANI films up to 12 wt.% of aniline absorbed concentration, while PA6/PANI films needed no more than 9 wt.% to reach maximum wettability. This behavior was in good correlation with the microstructure of the films. SEM micrographs showed uniform surfaces for both films formed above these respective concentrations, where wettability started to decrease. The films of PA/PANI seemed to be good candidates as dielectric layers in flexible electronics.