云母填充聚丙烯的界面和力学性质的研究

研究了云母填充聚丙烯体系,通过云母的不同表面处理改变填料的表面性质,以及添加接枝改性聚丙烯作为界面改性剂,考察了不同的界面状况对体系加工流动性以及材料力学性能的影响。实验结果表明,有机偶联剂等表面处理剂有助于填料的分散。带有机长链的处理剂可明显降低体系的熔体粘度,但力学性能未提高,表现出界面润滑效应。硅烷偶联剂处理的云母与聚丙烯熔体的加工混合能接近于未处理体系,但熔混后压制的试样抗张强度显著提高,表现出界面“偶联”效应。添加少量的马来酸酐接枝聚丙烯,与带氨基的硅烷偶联剂相配合,可使填充聚丙烯的抗张强度和断裂伸长都大大提高,表现出界面的强偶联作用。

EFFECT OF THE INTERFACE ON THE PROPERTIES OF MICA FILLED POLYPROPYLENE

The processing behavior and the final mechanical properties of filled polymers are greatly controlled by the interface condition between filler and polymer matrix.The filled polypropylene(PP)with mica flakes treated with different surface modifier as well as addited of grafting polypropylene as an interface modifier was studied, for observing the effect of the interfacial situation of the concerning system on the processing features and the mechanical properties of the filled plastics.The results have shown that the use of coupling agents increases the affinity of PP for mica and improve the homogeneity of the composites.Mica coated with an organic long chain compound reduces the viscosity of the filled system, but hasn't improved the mechanical properties of composite, because the modifier occupies the surface area of mica and likes an interfacial lubricant. By addition of mica flake treated with silane coupling agent, the energy requirement for mixing the componends has no conspicuous change as compared with that of untreated system, but the tensile strength, elongation and flexural strength increase obviously. The addition of a small amount of maleated polypropylene, besides the amino-silane treatment of the filler, further increase the strength and elongation of the composite.An strong coupling effect between those two phases has been displayed.