Search

The synthesis of triple‐layer‐structured polyaniline (PANI) conductive nanocomposites, including two‐dimensional leaf‐shaped and three‐dimensional flower‐shaped types (S‐PANI), via a two‐step method is proposed in this study. According to scanning electron microscopic measurement, the triple‐layer‐structured S‐PANI consists of a middle layer of nonconductive PANI (N‐PANI) at 100 nm thickness and emeraldine‐salt‐form PANI (ES‐PANI) nanolayer at 40–50 nm thickness. The results of Fourier‐transform infrared spectroscopy, UV/Vis spectroscopy, and X‐ray diffraction pattern demonstrate that the phenazine unit existed within the N‐PANI main chain, leading to the poor conductivity of N‐PANI. However, the conductivity of the N‐PANI can be extremely enhanced by at least nine orders of magnitudes (<10−9–100 S/cm) when a conductive ES‐PANI nanolayer is further grown on the N‐PANI outer surface. Finally, the results of oxygen transmission test and electrochemical impedance spectroscopy reveal that the leaf‐shaped S‐PANI, as an additive in epoxy resin, has the best oxygen barrier property (oxygen transmission rate = 5.86 cm3 m−2 day−1) and highest coating resistance (5.53 × 1010 Ω) after 60‐day immersion in 0.1 M HCl solution, indicating that the leaf‐shaped S‐PANI is an excellent anticorrosion additive. [ABSTRACT FROM AUTHOR]