聚合物熔体在圆锥短口模的挤出胀大方程

深入讨论了聚合物熔体在不同长径比、不同角度圆锥短口模的挤出胀大现象及机理，利用生产用挤出机进行不同角度的圆锥短口模实验。结果表明，圆锥短口模挤出过程中，熔体在收敛流道受到拉伸流变，导致强烈的入口弹性效应，表现为熔体在短口模挤出时显著的挤出胀大。理论和实验研究结果进一步表明不同圆锥口模入口角对实验材料表现出有不同的挤出胀大值。

A New Extrusion Swell Equation for Polymer Melt at Conical Short Die

Extrusion swell phenomenon and mechanism of polymer melts in conical short die with different entrance angles and different aspect ratio were discussed. Different conical short dies with various angles were studied on an industrial extruder. The result shows that the extensional flowing of the melt occurs in convergent die resulting in intense entrance elastic effect and distinct extrusion swell. Theoretical and experimental analyses show that different entrance angle of die is responsible for the degree of the extrusion swell.