Preparation and properties of poly(urethane acrylate) (PUA) and tetrapod ZnO whisker (TZnO-W) composite films

Tetrapod zinc oxide whiskers (TZnO-Ws) were successfully synthesized via a thermal oxidation method and confirmed using Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. A series of poly(urethane acrylate) (PUA)/TZnO-W composite films with various TZnO-W contents were prepared via a UV curing method and their physical properties were investigated to understand their possible use as packaging materials. The morphological, thermal, mechanical, antibacterial and barrier properties of the PUA/TZnO-W composite films were interpreted as a function of TZnO-W content. The thermal stability, barrier properties and antibacterial properties of the composite films, which were strongly dependent upon their chemical and morphological structure, were enhanced as the TZnO-W content increased. The oxygen transmission rate and water vapor transmission rate decreased from 614 to 161 cm3 m-2 per day and 28.70 to 28.16 g m-2 per day, respectively. However, the mechanical strength of the films decreased due to the low interfacial interaction and poor dispersion with high TZnO-W loading. The enhanced barrier properties and good antibacterial properties of the PUA/TZnO-W composite films indicate that these materials are potentially suitable for many packaging applications. However, further studies are needed to increase the compatibility of polymer matrix and filler. (C) 2012 Society of Chemical Industry