Effects of synthesised polyaniline (PAni) contents on the anti-static properties of PAni-based polylactic acid (PLA) films

Abstract

An anti-static polymer film was prepared using biodegradable poly(lactic acid) as a matrix and polyaniline (PAni) as an anti-static agent. It is aimed to be applied in packaging applications to dissipate the accumulated charges. The anti-static properties of PLA films were investigated with various PAni contents ranging from 0% to 20% through ex situ polymerisation by the solution casting method. PAni was synthesised in the solution form through chemical oxidation at 0 °C. The synthesis of PAni was confirmed by Fourier transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV-Vis) absorption spectroscopy. The mechanical and anti-static properties of the samples were characterised using a Universal Testing Machine (UTM) and a resistivity meter, respectively. The experimental results indicated that incorporation of PAni into PLA films affected the morphology, anti-static and mechanical properties of the samples. PLA/PAni showed a compact surface with a porous structure, reflecting the interfacial interaction between PLA and PAni in the presence of a plasticiser. It was discovered and compared with other compositions, PLA with 15% PAni exhibited excellent anti-static performance with 2.45 × 10¹⁰ ohm/sq surface resistivity and the highest tensile strength, elongation at break and modulus of 29.3 ± 2.4 MPa, 60.1 ± 1.6% and 1364.0 ± 85.2 MPa respectively. Hence, PAni is a good candidate to be used in PLA/PAni systems by giving a suitable surface resistivity that can potentially be applied in anti-static packaging applications.