PCL/ZnO Bio-friendly Films as Food Packaging Material.Thermal and morphological analysis

Films of Poly(-caprolactone) (PCL) and PCL/Zinc Oxide (ZnO) were obtained by solution processing. Thermal behaviour and morphological structure were analysed by means of Thermogravimetry (TGA), Differential Scanning Calorimetry (DSC), Optical Microscopy (OM) and Scanning Electron Microscopy (SEM). The addition of ZnO to PCL decreased the degradation temperature about 50-70°C; the films are thermally stable up to 200°C, making them suitable for packaging hot grilled chicken. ZnO did not promote significant alterations of the PCL fusion and melt crystallization, however the crystallinity increased; probably ZnO acts as nucleating agent during PCL crystallization as OM images showed greater amount of small spherulites on PCL/ZnO films. According to SEM, the methodology utilized is adequate for producing films in concentrations up to 5% ZnO. Keywords: PCL, ZnO, Thermal behaviour, Morphological structure.