聚合物振动诱导单螺杆熔融塑化过程(Ⅱ) 轴向振动对熔融过程的影响

Melting and plasticizing process of vibration induce single-screw extruder (Ⅱ) Effect of axial vibration on melting process

在本文(Ⅰ)报所建立的物理模型以及解析模型的基础上,推导出振动诱导单螺杆挤出机的熔融段长度和固体床分布方程.使用低密度聚乙烯(LDPE)进行实例计算,得出熔融速率随振动频率和振幅的增加而增加,熔膜厚度和熔融段长度随振动频率和振幅的增加而减少.当振动强度达到某一极限值后,熔融速率、熔膜厚度和熔融段长度不再随振动参数的变化而变化.最后运用剖分料筒实验验证了上述结论的正确性,理论计算值与实验结果符合得很好.

With the help of physical and analytical models of melting and plasticizing described in the first report, the melting length and the solid bed distribution expressions of vibration induced single-screw extruder were presented. Low-density polyethylene （LDPE） was used in the calculation, and some conclusions were obtained. Melting rate increased, while thickness of melt film and melting length decreased with the increase of vibration frequency and amplitude. However after vibration intensity reached a limit value, melting rate, thickness of melt film and melting length would remain unchanged. In the end, the half open barrel visualization experiment was used to prove the validity of the conclusion. Calculations were in good agreement with the result of experiment.