三元乙丙橡胶挤出压力振荡现象的影响因素

Effect factors on extrusion pressure oscillation phenomena of ethylene-propylene-diene rubber

采用恒速型双筒毛细管流变仪研究了剪切速率、口模温度和含氟弹性体偏氟乙烯-六氟丙烯-四氟乙烯共聚物(PPA)对三元乙丙橡胶(EPDM)挤出压力振荡现象的影响。结果表明,EPDM高速挤出时,升高温度可以推迟挤出压力振荡现象的发生;振荡周期和振幅均随剪切速率的增加而减小;加入PPA可以改善EPDM挤出物的外观,且挤出压力低于纯EPDM,PPA质量分数越大,其降低幅度越大。

The influences of shear rate, die temperature, fluoroelastomer vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer （PPA） on the extrusion pressure oscillation phenomena of ethylene-propylene-diene rubber （EPDM） were systematically studied through a double capillary rheometer. The results showed that the extrusion pressure oscillation phenomena of EPDM was delayed with increasing temperature at high speed extrusion,the pressure oscillation period and the amplitude were decreased with the increase of shear rate. The appearance quality of EPDM melt was improved with adding PPA. The extrusion pressure was lower than that of pure EPDM, and its decreasing range was larger with increasing mass fraction of PPA.