石蜡油对动态硫化EPDM/PP热塑性弹性体力学性能的影响

Influences of Paraffin Oil on Mechanical Properties of Dynamic Vulcanized EPDM/PP Thermoplastic Elastomer

通过双螺杆挤出机制备了动态硫化三元乙丙橡胶（EPDM）/聚丙烯（PP）热塑性弹性体。运用抽提法测试了该EPDM/PP弹性体的凝胶含量,并采用万能试验机等对其力学性能进行测试,研究了软化剂石蜡油的添加量对动态硫化EPDM/PP热塑性弹性体力学性能的影响。结果表明：当石蜡油添加量为20%时,EPDM/PP共混物的凝胶含量最大;当石蜡油添加量为25%时,EPDM/PP共混物的拉伸强度和断裂伸长率均达到最大值。此外,石蜡油的引入不仅能降低EPDM/PP热塑性弹性体的硬度和压缩永久变形,还能提高材料的耐热氧老化性能,其适宜添加量为20%-25%。

The thermoplastic elastomers with ethylene-propylene-diene monomer（EPDM） rubber/polypropylene（PP） as the matrix were prepared by twin screw extruder. The gel content was measured with extraction method and mechanical properties were tested by an universal test machine. The influences of paraffin oil on mechanical properties of dynamic vulcanized EPDM/PP thermoplastic elastomer was studied. The results show that： when the paraffin oil content is 20%, the maximum gel content of EPDM/PP blends can be obtained; when the paraffin oil content is 25%, both the tensile strength and elongation at break reach the maximum. The hardness and compression set reduce and the resistant aging properties increase with the addition of paraffin oil, and 20%-25% of paraffin oil is suitable.