Thermoplastic vulcanizate(TPV) was prepared using polypropylene(PP) and ethylene propylene diene terpolymer (EPDM) by means of dynamic vulcanization.The rheological behavior of TPV blend melts was measured using a capillary rheometer.The effects of extrusion temperature and shear rate on the rheological properties of the blend melts were studied,and the flow behavior in capillary extrusion was also investigated.The results showed that the shear stress of the blend melts increased with the increase of shear rate and decreased with the increase of extrusion temperature;the viscosity decreased with the increase of shear rate and extrusion temperature;the die swell rate increased with the increase of flow rate and extrusion temperature;the die pressure drop rose with increasing flow velocity and capillary length.%以聚丙烯(PP)和三元乙丙橡胶(EPDM)等为原料，采用完全动态硫化共混技术制备EPDM／PP热塑性弹性体(TPV)，使用毛细管流变仪对TPV熔体的流变特性进行测试。分别研究了剪切速率、挤出温度对黏度、剪切应力和挤出胀大比的影响，以及不同条件下熔体流过毛细管口模时流速对压力降的影响。结果表明，TPV熔体是假塑性流体，其剪切应力随剪切速率增大而增大，随挤出温度的升高而降低；黏度随剪切速率和挤出温度的增大而降低；挤出胀大比则随剪切速率和挤出温度的增大而增大；毛细管口模的压力降也随流速和毛细管口模长度的增大而增大。
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