振动力场对聚合物挤出胀大的影响

Effect of the vibration force field on the polymer extrusion swell

为了改善聚合物材料的挤出胀大现象,将振动力场引入聚合物的挤出过程.采用动态毛细管流变仪对不同振动参数下的挤出胀大进行研究,建立了相应的物理模型和数学模型,并借鉴前人的工作成果,运用数学推导得到了挤出胀大与振动参数间关系的解析式.研究表明:随着振动频率和振幅的增加,挤出胀大呈非线性减少,并最后趋于稳定.

In order to improve the polymer extrusion swell phenomenon, the vibration force field was intro-duced into the process of the polymer extrusion. The dynamic capillary rheometer experiment was performed to research the effect of the vibration parameters on the extrusion swell. Physical and mathematic models about polymeric material flowing in electromagnetism dynamic capillary rheology equipment were established, and with the help of former work and complex mathematic deduction, the analytical expressions about the relation-ship between extrusion swell and vibration parameters were obtained. The experimental results well agree with the calculation. The study shows that the employment of vibration field can lower polymer laxity time and re-new the elasticity quickly, decrease melt viscidity and exit pressure, and accelerate human molecule untie-tangle, all of which lead to the decrease of the extrusion swell and improve the quality of producted. The presented model enables the prediction of processing parameters for polymer extrusion, from which the optimum operating conditions can be obtained.