转矩流变仪表征熔融聚合物的流变性能

摘要

采用温度校正后的转矩流变模型,研究了结晶与非晶聚合物的流变性能,并将流变结果与毛细管流变仪进行对比.结果表明,在非牛顿指数及流动活化能测量方面,转矩流变仪与毛细管流变仪测量结果差异较小;由于黏滞耗散作用,转矩流变仪在进行流变表征时需要进行转矩的温度校正;转子等效半径与几何结构有关,而与物料种类及加工条件无关;转矩流变仪测量的剪切速率范围较窄.%A temperature corrected equation is developed to measure theological parameters of the crystalline and amorphous polymer in torque rheometer, and theological results were compared with capillary rheometer results. The results showed that the activity energy and flow index data measured with torque rheometer were in good accordance with those measured with capillary rheometer. When measuring the rheological parameters, the torque values measured should be corrected for the temperature rise due to viscous dissipation. Equivalent radius was a quantity depending only on geometrical dimensions of the mixer but independent of the nature of the fluid and the mixing conditions. Torque rheometer has a narrow range of shear rate.