原位固相接枝CaCO_3/聚丙烯复合材料中界面相互作用与力学性能的关系

The Relationship Between Interfacial Interaction and Mechanical Properties of Polypropylene Composites Filled with Surface-Modified Calcium Carbonate by Solid Phase Grafting In-Situ

用马来酸酐(MAH)在碳酸钙(CaCO3)表面引入双键,通过原位固相接枝法将聚丙烯蜡(PPW)化学键合在CaCO3表面,制得3种不同PPW接枝率的CaCO3-MAH-PPW,测定CaCO3和PP的接触角,计算其表面张力、界面张力和粘附功,探讨这些因素与复合材料界面相互作用和力学性能的关系。结果表明,PP与CaCO3之间的相互作用和复合材料的力学性能同它们之间的粘附功与界面张力的比值大小趋势相同,这一结果与通过动态力学性能得到的界面相互作用强弱顺序一致。因此可把粘附功与界面张力的比值作为衡量PP/CaCO3之间相互作用强弱、力学性能好坏的重要参数,为合理地选择和改性填料提供科学判据。

Calcium carbonate （CaCO3） of which the surface was pretreated with maleic anhydride （MAH） to introduce double bond groups, was grafted with polypropylene wax （PPW） via solid phase grafting in-situ to prepare modified CaCO3 with different chemical grafting efficiency of PPW. The contact angles of PP and different CaCO3 were tested. The surface energy, interfacial tension and adhesion work were calculated. The effects of these factors on the interfacial adhesion of CaCO3/ PP and mechanical properties were researched. The results show that the tendency of interfacial interaction between CaCO3 and PP as well as mechanical properties of the composites is the same as that of the ratio of their adhesion works to interfacial tension. This result is consistent with the sequence of interfacial interaction obtained from dynamic mechanical measurement. Thus the ratio of adhesion works to interfacial tension between CaCO3 and PP can be used as an important parameter to measure interfacial interaction and mechanical properties of the composites, which provide the scientific criterion to select and modify fillers.