外场下聚丙烯/聚苯乙烯共混体系的流变行为

利用自主研制的多功能全电动式聚合物流变特性测试仪,研究了不同组分配比、温度和振动参数对聚丙烯/聚苯乙烯共混物流变特性的影响.研究结果表明:在低剪切速率范围(剪切速率＜400 s-1)内,所得共混物的黏度随着共混体系中聚苯乙烯含量的增加先下降后升高,临界聚丙烯与聚苯乙烯的质量之比约为1∶1；当剪切速率较高(剪切速率＞400 s-1)时,共混物的黏度受组分配比的影响不大,但是其壁面剪切应力升高.振动频率对共混体系流变特性的影响具有波动性,对于质量之比为4∶6的聚丙烯/聚苯乙烯共混体系,15 Hz为其最佳加工工艺参数.振幅可以有效地降低共混体系的壁面剪切应力与熔体黏度.振动力场的引入,有效降低了聚合物的加工温度,达到与升高温度相同的效果,有效地节约了能源消耗,对聚合物的成型具有重要意义.

Rheological Properties of PP/PS Blends in Vibration Force Field

Rheological properties of Propylene/Polystyrene blends with different mass ratio under different temperature and vibration conditions were investigated by using self-made multifunctional all-electric polymer rheometer. The result showed that: The viscosity of blends increased after a decline with the increase of Polystyrene content within a lower shear rate range (< 400 s-1). The critical mass ratio of Polystyrenes to Propylene was 1:1. However, the viscosity of blends was hardly influenced by the mass ratio within a higher shear rate range (> 400 s-1) and the wall shear stress increased. The influence of vibration frequency on blends rheological property fluctuated. As for the blends with the mass ratio of 4:6, the optimized processing parameter was 15 Hz. The vibration amplitude effectively reduced the wall shear stress and viscosity of the blends. The introduction of vibration force field into polymer processing can significantly lower the processing temperature, effectively save energy consumption and is important for polymer molding.