挤出反应温度与剪切应力对动态硫化PP/EPDM性能的影响

采用动态硫化的方法,在双螺杆挤出机中制备了聚丙烯(PP)/三元乙丙橡胶(EPDM)热塑性弹性体,研究了挤出反应温度与螺杆转速提供的剪切应力对动态硫化PP/EPDM热塑性弹性体性能的影响。结果表明,适当提高挤出反应温度或螺杆转速可提高PP/EPDM热塑性弹性体的拉伸强度、拉断伸长率和凝胶含量,当挤出反应温度为200℃、螺杆转速为600 r/min时,热塑性弹性体的综合拉伸性能最好,拉伸强度为19.87 MPa,拉断伸长率为527.3%,凝胶含量为54.69%。高螺杆转速提供的高剪切应力可在一定程度上提高PP/EPDM热塑性弹性体的熔融温度。

Inlfuences of Extrusion Reaction Temperature and Shearing Stress on Properties of Dynamic Vulcanized PP/EPDM Thermoplastic Elastomer

Using dynamic vulcanization method,PP/EPDM thermoplastic elastomers were prepared in the twin screw ex-truder. The effects of extrusion reaction temperature and shearing stress generated by screw rotation speed on the properties of the dynamic vulcanized thermoplastic elastomers were studied. The results indicate that improving the extrusion reaction temperature or screw rotation speed properly can increase the tensile strength, elongation at break and gel content. When the extrusion reaction tem-perature is 200℃,screw rotation speed is 600 r/min,the comprehensive tensile properties of the thermoplastic elastomer is best, the tensile strength is 19.87 MPa,the elongation at break is 527.3% and the gel content is 54.69%. The higher shearing stress gener-ated by higher screw rotation speed can improve the melt temperature of the thermoplastic elastomer to some extent.