云母微粒对聚丙烯流变性能及热性能的影响(英文)

Influence of Mica Particles on Rheological and Thermal Properties of Polypropylene

采用毛细管流变仪测试云母微粒/聚丙烯(PP)共混熔体的流变性能,用热重分析仪研究云母微粒对PP热稳定性能的影响。结果表明:云母微粒/PP共混熔体属于非牛顿假塑性流体,其表规粘度随剪切速率的增大而减小;随着云母微粒含量的增加,熔体的流动性能基本呈下降趋势,但当云母质量分数为4%时,熔体的粘度接近于纯PP:温度升高使得熔体表观粘度降低,非牛顿指数增加:在相同剪切速率下,云母含量的增加对其混熔体粘流活化能的影响不大;添加云母微粒后可以显著提高PP的热稳定性能。

The influence of mica particles on the rheological and thermal properties of polypropylene(PP)/mica composites were investigated by capillary rheometer and TG.The results display that the PP/mica blends show a non-Newtonian pseudoplastic flow behavior and the viscosity decreases with the increasing of the shear rate.It is worth pointing out that the flow behavior of melting PP/mica composites decreases with the increasing of the content of mica,while the apparent viscosity of the blends is similar to that of the pure PP when the content of mica particles is about 4 wt%.With the rise of temperature,the apparent viscosity decreases and the non-Newtonian index increases.On the other hand,the activation energy of PP/mica is very close to that of PP as the shear rate is same,but the thermal stability of the modified PP is significantly improved by the addition of mica particles and the application range of PP is developed.