纳米粉体/聚丙烯复合材料的制备及力学性能研究

【作者】 朱国亮；

【导师】 杨辉； 葛曼珍；

【作者基本信息】 浙江大学 ， 材料加工工程， 2002， 硕士

【摘要】 本课题主要研究纳米CaCO₃、SiO₂和TiO₂粉体改性聚丙烯（PP）后材料的力学性能及其增强机理，同时还对钛酸酯偶联剂改性纳米CaCO₃粒子的最佳含量以及偶联剂的加入对复合材料的力学性能的影响进行了研究，并对纳米CaCO₃粒子和微米CaCO₃粒子分别填充PP的力学性能进行了比较分析。 论文中对CaCO₃粒子进行了粒度与比表面测试分析，对经钛酸酯偶联剂表面改性的纳米CaCO₃粒子进行了红外吸收光谱分析，对改性后的复合材料进行了力学性能测试、差热扫描量热分析、X射线衍射谱、红外吸收光谱、透射电镜、扫描电镜等分析，讨论了样品中结构和性能之间的关系。 研究结果表明：纳米粒子相对微米粒子对PP有更好的力学改善效果；对纳米粒子的表面改性存在一个最佳的偶联剂掺入量；经偶联剂表面改性后的纳米粒子较未表面改性的纳米粒子更能改善PP的力学性能，特别是冲击强度有较大程度的改善。但是当掺入量较大时，由于团聚现象的大量出现，导致各项力学强度随着掺入量的增加而降低。 通过XRD和DSC分析发现，纳米粉体对β-pp有诱导生成作用：通过SEM分析发现表面改性后的纳米粒子填充即后，与PP基体结合较好，基体在冲击方向存在层状滑移，并有纤维状形变，显示基体发生了剪切屈服形变。同时我们发现纳米粒子可以阻止裂纹的进一步开裂，最终终止裂纹。通过TEM分析发现经过表面改性后的纳米粒子比未改性的纳米粒子在PP中具有更好的分散性，分散性的改善更有利于诱导β-PP的生成以及诱导基体发生剪切屈服形变，正是这种结构上的变化导致了力学性能的改善。更多还原

【Abstract】 In this thesis we have studied the toughening and strengthing modifications of polypropylene (PP) by nano-particle such as CaC03) Si02 and Ti02. The performance of modified polypropylene and the modifying mechanism have been introduced. We have also explored the furthest dosage of Titanate coupling agent in CaC03/PP and the influence of coupling agent to the composites by the determination of the mechanical properties. Furthermore, we compared the mechanical properties between the modified nano-CaC03/PP and unmodified nano-CaC03/PP.We have investigated the composites by means of mechanical testing, DSC, XRD, FT-IR, TEM, SEM, etc. The relation between the structure and property of the composites has been discussed in this thesis. We studied the nano-particles by means of LS particles size analysis , we also studied the modified nano- CaC03 by means of FT-IR.The result show that PP filled with nano-particles has better mechanical performances than which filled with micron-particles. There is some furthest dosage of Titanate coupling agent in CaC03/PP. The mechanical properties of the modified nano~CaC03/PP is better than that of unmodified nano-CaC03/PP, especially the impact strength has been improved greatly. But when the dosage of nano-particles is too much, those nano particles will accumulate and this will lead to decreasing of strength of the material.Through investigated of XRD and DSC, we found that ?-PP was formed by addition of nano-particles. The distribution of modified and unmodified nano-particles in PP were studied by means of TEM, it showed that modified nano-particles dispersed much better than the unmodified nano-particles. The improved contribution of nano-particles lead to more(3 -PP formed and microscopic damage, all those structural changes caused the improvement of the mechanical properties.更多还原