拉伸条件下液态Sn/熔融聚乙烯复合体系中Sn的纤维化及其机制

低熔点金属与聚合物复合不仅可以产生高性能的导电和导热复合材料,还为聚合物多相多组分体系的研究提供了新的模型。为系统认识低熔点金属液体/聚合物熔体复合体系在外场作用下的结构变化,首先通过光学显微镜研究了拉伸条件下液态Sn/熔融聚乙烯复合体系中Sn液滴的纤维化现象;然后,测量了不同拉伸程度下Sn/聚乙烯复合体系中Sn粒子的尺寸,并研究了拉伸程度对Sn粒子尺寸的影响;最后揭示了Sn液滴纤维化的机制。结果表明:在液态Sn/熔融聚乙烯复合体系的拉伸过程中,Sn液滴的直径越大,则越先开始纤维化;纤维状Sn粒子的直径由复合体系的拉伸程度决定,而其长度则由Sn液滴的体积决定。所得结论可为高性能金属/聚合物复合材料的制备提供理论指导。

Fibration of Sn in liquid Sn/molten polyethylene composite system under tensile condition and its mechanism

The combination of low-melting-point metal and polymer can not only yield electrically and thermally conductive composites with high performances, but also provides a new model to the investigation of multiphase and multi-ingredient polymer systems. In order to recognize the structure changes of low-melting-point metal liquid/polymer melt composite system under outfield effect systematically, the fibration phenomenon of Sn droplets in liquid Sn/molten polyethylene composite system under tensile condition were studied by optical microscope firstly. Then, the size of Sn particles in Sn/polyethylene composite systems at different tensile degrees was measured and the effect of tensile degree on the size of Sn particles was investigated. Finally, the fibration mechanism of Sn droplets was revealed. The results show that during the tensile process of liquid Sn/molten polyethylene composite system, the greater the Sn droplet diameter is, the earlier begins to fiberize. The diameter of fibrous Sn particles depends on the tensile degree of composite system, and the length depends on the volume of Sn droplet. The obtained conclusions can provide theoretic guidance to the preparation of metal/polymer composite with high performances.