Physicochemical and Antimicrobial Properties of Gamma Irradiated HPMC-ZnO BNC Films

This work presents the effect of gamma irradiation on the physicochemical, mechanical, thermal and antibacterial properties of HPMC/ZnO bionanocomposite (BNC) films exposed to a Cobalt - 60 gamma source of average energy 1.25 MeV for various (0250 kGy) doses. X-ray diffraction (XRD) study revealed that the crystallite size (L-XRD in A) and crystallinity of the nanocomposites significantly increased up to 100 kGy, then decreased as the radiation dose increased. At lower dosage nanocomposites showed improved Young's modulus and load capacity, and at higher dosage, the decrease in tensile strength (TS) and percentage elongation at break (E), suggesting degradation process in the HPMC matrix. Contact angle (CA) studies demonstrated HPMC/ZnO nanocomposites are more hydrophilic after gamma irradiation. The antibacterial activity of HPMC/ZnO nanocomposite films were effective even after gamma irradiation, making it suitable for food and pharmaceutical packaging applications. (C) 2018 Elsevier Ltd. All rights reserved.