微米二氧化硅改性聚丙烯复合材料的力学性能研究

Research of mechanical properties of polypropylene composites with micro-silica modified by ball-milling grafting polymerization

以球磨接枝方式制备了聚丙烯酸酯(PBA)接枝微米级二氧化硅,并通过转矩流变仪与聚丙烯(PP)熔融共混得到接枝微米二氧化硅改性聚丙烯复合材料.利用红外光谱、热重分析、万能力学试验机、扫描电镜技术研究了球磨接枝原理以及复合材料的性质.结果表明,球磨过程中,PBA通过化学键的形式接枝到微米二氧化硅表面,使其在聚丙烯集体中得到较好的分散,而且粒子表面的接枝聚合物链与基体大分子链相互缠结,这样的结构增强了微米粒子与基体间的界面相互作用,从而对复合材料力学性能的提高起到了有利作用.

Polypropylene（PP） composites with polybutyl acrylate（PBA） and micro-silica modified by ball-milling grafting polymerization were prepared by a concentional melt compouding technique. The mechanism of the graft polymerization and the structure of the microcomposites were studied by infrared spectroscopy （IR）,thermogravimetry（TGA）,universal material testing machine and scanning electron micro-scopy（SEM）. The results show that PBA has been grafted to the surface of micro-silica by chemical bonds during the ball-milling grafting polymerization.The modified micro-silica particles were homogeneously dispersed in PP matrix and a strong interfacial interaction were established by the chain entanglement between the grafted polymer and the matrix,which is highly beneficial to increase the toughening and tensile strength of the composites.