Study On The Properties Of Weathering And Spectrum Of Inorganic Particle-Polypropylene Composites

Polypropylene (PP) is one of the most widely used materials in plastic industry, with easy synthesizing, well performance in mechanics, high thermo-transmogrification and low absorbing. In this paper, we studied the properties of weathering and UV-Vis spectrum and FT-IR spectrum of the Propylene composite filled with nano-TiO₂,nano-ZnO,bulk-TiO₂ systematically. Using analyzing ways, such as XRD,SEM,TEM, we investigated changes of mechanical properties of composite materials between un-weathering and weathering. And with studying the UV-Vis spectrum and FTIR spectrum, we analysed the factors and mechanism of weathering of polypropylene composites. From these studies we could conclude that it could improve the performance of weathering of polypropylene materials to fill with nano-TiO2 or nano-ZnO or bulk-TiO₂. And when blending with some organic ultraviolet stabilizer and ultraviolet absorber, we found that this blending could improve the property of weathering remarkably and long, for this blending could bring coordinated reaction. We found the UV-Vis absorbance and transmittance spectrum of inorganic particle-Polypropylene after weathering in the accelerated aging box, and we found that the values of ultraviolet absorbance of composites decreased more slow than pure polypropylene, and these samples filled with nano-TiO₂, or with nano-ZnO or with bulk-TiO₂ , performance was the best, reversly their ultraviolet transmittance was slowly increased with weathering time. But the composite blending only with some organic ultraviolet stabilizer and ultraviolet absorber, this improvement was very feeble, because the stability of organic ultraviolet stabilizer and ultraviolet absorber was not good, they would been decomposed when explored under the ultraviolet light. But inorganic particles ( nano-TiO2,nano-ZnO and bulk-TiO2) could scatter the ultraviolet light and protected the organic ultraviolet stabilizer and ultraviolet absorber from decomposing, and let the organic ultraviolet stabilizer and ultraviolet absorber play more long and well. From results of the FTIR transmittance spectrum of polypropylene composites, we could found, for autor-theromooxidation of polypropylene during processing, that there was the spectrum apex of carbonyl group in 1643¹850cm-1 wave number, and the intensity of carbonyl group increased and the spectrum apex in 1643¹850cm-1 wave number broadened with aging time. While blending inorganic particles ( nano-TiO2,nano-ZnO and bulk-TiO2) we could find that this changes slowly and feebly. That could not change the mechanism of weathering of polypropylene composites to fill with inorganic particles ( nano-TiO2,nano-ZnO and bulk-TiO2) and just slow the weathering process.