【摘要】 通过熔融共混过程中原位接枝的方法制得聚丙烯酸丁酯接枝改性纳米二氧化硅/聚丙烯(SiO2-g-PBA/PP)复合材料,探讨了材料制备的最佳工艺条件,研究了复合材料的机械性能、结晶性能、微观形貌以及动态黏弹行为。结果表明,少量纳米粒子(体积分数≤1.36%)的加入即可对PP起到同时增强增韧的作用,制备SiO2-g-PBA/PP的适宜工艺条件为熔融共混温度180℃,共混时间10 min,转子转速60 r/min。对复合材料结晶行为的研究表明,纳米粒子的成核效应使PP的结晶速率加快。微观形态观察表明,纳米粒子与聚合物基体间具有良好的界面结合,这一点从对材料动态黏弹行为的研究中得到进一步证明,从而阐明了纳米粒子增韧增强聚合物的机理。更多还原

【Abstract】 Nanocomposites consisting of polypropylene homopolymer filled with in-situ grafted nano-silica were prepared by a conventional melt compounding technique.The influence of processing conditions on the mechanical properties of the nanocomposites was discussed.The mechanical performance,crystallization behaviors,morphology and dynamic mechanical behaviors of the nanocomposites were studied.It can be concluded from the results that the notched Charpy impact strength is significantly increased and a toughening effect can be attained by adding low loading(volume fraction ≤1.36%) of the in-situ grafted nanoparticles.Meanwhile,the tensile strength can also be increased.The reasonable processing conditions of the mixer can be set as 180 ℃ for 10 min with the rotation speed of 60 r/min.Studies of the crystalline characteristics indicate that addition of nanoparticles increases the rate of crystal-lization of PP.Filler/matrix interaction is enhanced due to interdiffusion and entanglement between the grafting polymer and the matrix,which is also emphasized by studies of the dynamic viscoelastic behavior and elucidates the toughening and reinforcing mechanism of nanoparticles.更多还原