高等级HDPE管材树脂毛细管流变性能研究

摘要

采用单管毛细管流变仪,在不同温度下对高等级高密度聚乙烯(HDPE)管材树脂的熔体流动行为进行了研究,考察了剪切应力(τ<,w>)、剪切速率(γ)、挤出胀大及温度之间的关系.结果表明,高等级HDPE管材树脂熔体的剪切流动基本上服从幂律定律;熔体的表观黏度(η<,a>)对温度的依赖性大致上符合Arrhenius方程;η<,a>随τ<,w>和γ的增加而非线性减小;挤出胀大比随温度的升高而下降,随γ的增加呈非线性增大.%The influences of shear rate, shear stress and temperature on the flow properties of HDPE pipe were investigated by using capillary rheometer at different temperature.The results showed that the melt shear flow obeyed roughly the power law; the dependence of the melt apparent shear viscosity on the temperature corresponded approximately with the Arrhenius equation; the melt apparent shear viscosity of HDPE pipes decreased nonlinearly with the increase of shear rate and shear stress; the melt extrude swell ratio decreased with increase of the temperature, however it was increased nonlinearly with increasing the shear rate.