Antimicrobial performance and charge transport mechanism of Poly(N-methylpyrrole)-boron nitride composite

Abstract

This study reports structural, dielectric and antibacterial properties of Poly(N-methylpyrrole)-Boron nitride (PNMPy-BN) composite synthesized via an interfacial polymerization method. Characterization and morphological analyses were performed by Fourier transform infrared (FT-IR), X-ray diffraction (Xrd), Fluorescence (FL), Thermogravimetric (TG), Scanning electron microscopy (SEM) and Atomic Force Microscope (AFM) analyses. Temperature-dependent dielectric measurements were carried out by an LCR meter. For the antimicrobial activity tests, the disk diffusion method was used. BN nanoparticles decreased the π-π stacking distance of the polymer chains, while they showed a quenching effect on the fluorescence emission intensity of polymer matrix. For the degradation process of PNMPy, the extrapolated onset temperature increased from 292 to 317 °C after filling process. Surface analyses showed that BN nanoparticles reduced the average roughness and size of agglomerated structures on the polymer surface. In dielectric analysis, it was determined that the conduction mechanism of PNMPy and its composite was compatible with the correlated barrier hopping (CBH) model, but for the composite there was a little tunneling effect in the conductivity at high temperatures. Furthermore, filling process decreased the minimum hopping distance of the charge carriers in the polymer matrix. BN nanoparticles increased the inhibition zone diameter of PNMPy between 2 and 8 mm against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis bacterial species.