【摘要】 用挤出-拉伸-注塑法制得了增强HDPE/PA66原位成纤复合材料,以不拉伸的普通共混材料作对照,研究了PA66质量含量(cm)对PA66成纤性和材料拉伸强度(σt)及模量(E)的影响及其作用机制。结果表明,当cm由0增至25%时,原位形成的PA66纤维数量增多,纤维横向尺寸及其分散性在cm=15%前减小在其后增大;材料的σt、E在cm=15%时分别比纯HDPE提高45%和60%。熔体拉伸时分散相液滴的聚结-形变成纤是PA66纤维形态随cm变化的关键因素,分散相对基体增强效应与两相界面缺陷效应综合作用,分散相对基体增刚效应受分散相形态控制,分别是决定材料的σt-cm、E-cm关系的支配因素。更多还原

【Abstract】 The reinforced HDPE/PA66 in-situ fiberized composites were prepared by extrusion-drawing-injection method.The influence of PA66 mass content(cm) on the PA66 fiberization,tensile strength(σt) and Young’s modulus(E) of the composites,together with their functional mechanisms were studied in contrast to the normal blended materials without drawing.The results showed that as cm rises from 0 to 25%,the number of PA66 fibers in-situ formed increases whereas their cross size and dispercity decrease till cm =15% and then increase.The σt and E of in-situ composites increase 45% and 60%,respectively,relative to neat HDPE at cm=15%.The fiberization of PA66 droplets through coalescence-deformation during melt-drawing plays a key role in the above variation of PA66 phase morphology with cm.The counterbalanced function between the reinforcing effect of dispersed phase on matrix and the interfacial flaw effect of the two phase and the rigidizing effect of fiber on matrix controlled by morphology of dispersed phase,are dominant factors of deciding the above σt ~ cm and E ~ cm relations,respectively.更多还原