摘要
在熔融挤出过程中,采用提高双螺杆挤出机螺杆转速所产生的高剪切应力诱导引发的方法及添加引发剂与提高螺杆转速的复合引发方法,研究了三元乙丙橡胶(EPDM)与马来酸酐(MAH)的官能化反应。结果表明,双螺杆挤出机的高螺杆转速所产生的高剪切应力作用可诱导EPDM的断链反应,引起官能化产物黏均相对分子质量的明显减小及接枝率与熔体流动速率的明显增大;在适量过氧化物类引发剂存在的条件下,此种高剪切应力作用可抑制EPDM官能化过程中的交联副反应,使产物的凝胶含量明显下降,接枝率及熔体流动速率明显增大;此种官能化反应过程易于控制,可制得接枝率0.80%～1.13%、熔体流动速率0.11～0.28g/min及凝胶质量分数不大于1.0%的MAH官能化EPDM。
The functionalization reactions of ethylene propylene diene monomer （EPDM） with maleie anhydride （MAH） were investigated in melt state through the high shear stress-induced initiation by increasing the screw rotation speed of twin-screw extruder and the initiation by both adding some initiator and increasing the screw rotation speed as well. The results showed that with the increase of screw rotation speed and reaction temperature, the grafting ratio and the meltflow rate of the functionalized products（EPDM-g-MAH） increased obviously, and the viscosity-average molecular weight decreased, implied that the grafting reaction consisted of the chain cleavage and the grafting reaction of the produced macroradicals with MAH. In the presence of peroxide initiator of an appropriate amount, the cross-linking reaction during melt extrusion could be suppressed by increasing the screw rotation speed, so the gel mass fraction decreased appriciately, and the grafting ratio and melt flow rate increased obviously. The process control of this method was easier than that of single peroxide initiation, and using this method the EPDM-g-MAH with grafting ratio of 0. 80% - 1.13% , melt flow rate 0. 11 - 0. 28 g/min and gel mass fraction not more than 1.0% could be obtained.
出处
《合成橡胶工业》
CAS
CSCD
2009年第1期29-32,共4页
China Synthetic Rubber Industry
关键词
高剪切应力诱导引发
三元乙丙橡胶
马来酸酐
官能化
引发剂
high shear stress-induced initiation
ethylene propylene diene monomer
malefie anhydride
functionalization
initiator
