【作者】 段小平；

【导师】 黄婉霞；

【作者基本信息】 四川大学 ， 材料学， 2005， 硕士

【摘要】 聚丙烯由于其合成方法简单,且具有力学性能均衡,热变形温度较高,吸水性低等优点,从而成为塑料工业里使用最多的品种之一。本文系统的研究纳米TiO₂、纳米ZnO和体相TiO₂粉体改性聚丙烯后材料的抗老化性能和UV-Vis光谱和FT-IR 光谱研究。结合XRD、SEM、TEM 等分析手段,研究了聚丙烯复合材料老化后的力学性能变化。并结合紫外-可见光谱和红外光谱研究,系统的分析了其复合材料的抗紫外老化性能的原因及机理。研究结果表明:添加纳米TiO₂、纳米ZnO和体相TiO₂,都对复合材料的老化后的缺口冲击强度和抗老化性能有一定程度的改善,当和一定量的有机紫外光稳定剂及有机紫外光吸收剂一同使用时,由于其协同作用,可以显著和持久的改善其抗老化性能。通过对改性后的复合材料在人工加速老化过程中的UV-Vis 吸收光谱和透射光谱研究,可以发现随着老化时间的延长,其紫外区的吸光性在加入纳米TiO₂、纳米ZnO 和体相TiO₂后,有了较大的改善,与纯聚丙烯树脂相比,吸收性能要好。而单独添加有机紫外吸收剂和紫外有机光稳定剂,其在紫外区的吸光性抗老化性能不是很理想,和无机粉体结合使用,可以明显的改善其在这方面的不足,充分发挥各自特点。而由于纳米TiO₂粒子的特性,其性能要优于体相TiO₂。运用红外光谱研究手段,分析了其复合材料老化过程中的分子结构变化,发现随着老化时间的延长,纯聚丙烯氧化分解, 1643¹850cm^-1 处的羰基吸收峰出现明显的增强和变宽。而当加入了有机紫外光稳定剂和有机紫外光吸收剂更多还原

【Abstract】 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.更多还原