A study on the protective effect of nano zinc oxide against weathering of wood-polypropylene composite

In this research, the effect of  using nano-zinc oxide (nano-ZnO) as a UV absorbent on the weathering resistance of wood- polypropylene composite was investigated. For this purpose, composite samples containing 0, 1, 2 and 3% nano-ZnO were manufactured using an internal mixer and a laboratory press. The prepared specimens were exposed to artificial weathering for 1480 hrs (in the periods of  0 ,480, 960 and 1480 hrs). The weathering degradation of specimens was monitored by tensile strength, hardness, colorimetry, Fourier transform infrared spectroscopy (FTIR), and, stereomicroscope tests. Results showed that weathering  caused color changes, tensile strength and hardness loss, physical and chemical degradation on the surface of the samples. The use of nano-ZnO partially prevented tensile strength and hardness loss of samples as well as their surface degradation.  In general, the use of 2% nano ZnO has been a better performance against weathering than other values.