聚甲醛共混物及复合材料挤出胀大行为的研究

Research on Die-swell Behavior during Extrusion of Polyformaldehyde Blends and Composites

采用共混方法制备了聚甲醛（POM）/高密度聚乙烯（HDPE）共混物和POM/HDPE/纳米碳酸钙（nano-CaCO3）复合材料,在温度（T）为170-220℃和载荷（F）为1.2-12.5 kg的条件下,应用流动速率仪考察了温度、载荷及HDPE用量（φ）等对共混物和复合材料熔体挤出胀大行为的影响。结果表明,复合材料的挤出胀大比（B）随着温度的升高而近似线性下降;挤出胀大比随着载荷的增加而非线性提高;挤出胀大比随着HDPE用量的增加而提高,两者间呈非线性关系。

POM/HDPE blends and POM/HDPE/nano-CaCO3 composites were prepared by melt blending method.The influences of temperature,load,and content of HDPE on the die-swell behavior of the blends and composites melts were investigated by using a melt flow index instrument when the temperature was in the range of 170~220 ℃ and load was from 1.2~12.5 kg.The results showed that the die-swell ration B of the blends decreased with a rise of temperature linearly,and increased with increase of the load and HDPE content non-linearly.