Preparing chitosan–Polypyrrole nanocomposite film andevaluation of its mechanical, electrical, and antimicrobialproperties

In this study, chitosan–Polypyrrole film was prepared with a combination of different concentrations ofPolypyrrole and various synthesis times to produce antimicrobial and biodegradable packaging film. Thephysical, electrical, and mechanical properties of the films were investigated. The interaction betweenchitosan and Polypyrrole was confirmed by Fouriertransform infrared spectroscopy (FTIR) and X-raydiffraction patterns. The size and morphology of the synthesized particles were examined by scanningelectron microscopy. The results indicated that the synthesized Polypyrrole particles had a spherical shape(۴۵–۱۱۱ nm). The antimicrobial and antifungal activity of the films against Aspergillus niger fungi(antifungal area: ۶۱.۴۶ mm۲ ) and Escherichia coli bacteria (antimicrobial area: ۱۲۶.۲۶ mm۲) increasedwith increasing the concentration of Polypyrrole. The results obtained from the study of the effect ofPolypyrrole on the electrical conductivity of the chitosan film showed that increasing the Polypyrroleconcentration and synthesis time resulted in decreased electrical resistance of the film, for which the filmwith the highest Polypyrrole concentration and the highest synthesize time had the lowest resistance.According to the mechanical property results, tensile strength (TS) and elastic modulus were increased due tothe addition of the Polypyrrole to the polymer matrix. The chitosan blank film had a lower TS thannanocomposites. As the final results, the chitosan–Polypyrrole film has good electrical conductivity,indicating thatthe produced film could be used in intelligent food packaging.

Keywords:

Chitosan , Polypyrrole , conducting polymer , nanocomposite , biodegradability