Zinc sulfide mediation of poly(hydroxybutyrate)/poly(lactic acid) nanocomposite film for potential UV protection applications.

The present study dealt with the fabrication of zinc sulfide (ZnS) nanoparticles (NPs), prepared using the chemical precipitation method, mediated poly(hydroxybutyrate) (PHB)/poly(lactic acid) (PLA) composite films employing the solution casting approach. The films were characterized based on structural, surface, chemo-physical, thermal, electrical, antibacterial, UV protection and degradation profiles. The results demonstrated the successful formation of nanobiocomposite films with good intercalation of the constituents. The surface morphology results expressed the placement of ZnS NPs in the polymeric blend as supported by elemental analysis. The XRD analysis exhibited the crystalline behavior of the nanobiocomposite films. The surface wettability analysis indicated that with the inclusion of ZnS NPs, the water contact angle of the resultant film was observed to be 119.57°. The prepared nanobiocomposite film exhibited thermal stability up to 214 °C and tensile strength of 25.0 ± 2.4 MPa as compared to that of native PHB (as 15.0 ± 1.5 MPa) and PLA (as 20.0 ± 2 MPa) films. The nanobiocomposite films expressed good antibacterial properties as compared to the control. The prepared films expressed the degradability trends in the natural environment. The ZnS NPs inclusion in the PLA/PHB blend could enhance the AC conductivity of the resultant nanobiocomposite film with acceptable UV protection properties applicable for UV protective packings.