FEP/PP共混物熔体挤出胀大行为研究

Research on Extrusion Swell Behaviour of FEP/PP Blend Melt

应用熔体流动速率仪考察了聚丙烯(PP)含量、温度、载荷及口模直径对FEP(聚全氟乙丙烯)/PP共混物熔体的挤出胀大行为的影响。结果表明,在试验条件下,FEP/PP共混物熔体的挤出胀大比(B)基本上随着温度的升高而线性增大,随着载荷的增加而非线性提高,随着PP含量的增加B略为下降;当口模直径小于1.500 mm时,B随着口模直径的增加急速减少,然后,B随着口模直径的增加显著增加。

The influences of PP content, die diameter, loading and temperature on the extrusion swell behaviour of FEP/PP blend melt were investigated by using a melt flow rate instrument. The results show that the die swell ratio （B） of the FEP/PP blend melt presents a approximately linear increase with an increase of temperature, a nonlinear increase with an increase of loading, and a slight decrease with an increase of PP content. When the die diameter （D） is less than 1. 500 mm, the B of the FEP/PP blend melt reduces quickly with an addition of D, whereas B increases obviously with an addition of D when D is more than 1.5 mm.