高剪切应力对苯乙烯-乙烯/丁烯-苯乙烯三嵌段聚合物马来酸酐化反应的影响  

Influence of high shear stress on functionalization of maleic anhydride with styrene-ethylene/butylene-styrene terblock polymer

作　　者：杜丽[1] 张玲[1] 张云灿[1] 

机构地区：[1]南京工业大学材料科学与工程学院,南京210009

出　　处：《合成橡胶工业》2013年第4期279-283,共5页China Synthetic Rubber Industry

摘　　要：通过提高双螺杆挤出机螺杆转速的应力引发方法,研究了高剪切应力下马来酸酐(MAH)与苯乙烯-乙烯/丁烯-苯乙烯三嵌段聚合物(SEBS)的官能化反应。结果表明,随着双螺杆挤出机螺杆转速的提高,官能化产物的接枝率和熔体流动速率明显增大。高剪切应力的作用引起大分子链断链,形成大分子自由基,从而引发SEBS的接枝反应。通过提高螺杆转速可有效地抑制交联副反应,制得接枝率较高(质量分数0.79%～0.89%)、熔体流动速率适宜(1.859～4.398 g/min)和凝胶含量较低(质量分数不大于0.32%)的官能化产物。同时,由应力诱导引发所得官能化产物SEBS-g-MAH对尼龙(PA 66)的增韧效果较好,其共混物的悬臂梁缺口冲击强度能达到约94 kJ/m2,较纯PA 66提高30余倍,而其拉伸和弯曲强度的下降并不剧烈。The functionalization reaction of sty- rene-ethylene/butylene-styrene terblock polymer （SEBS） with maleic anhydride （MAH） was investi- gated through the high shear stress-induced initiation by increasing the screw rotation speed of twin-screw extruder. The results showed that the percent of grafting and the melt flow rate of functionalized products （SEBS-g-MAH） increased obviously with the increase of screw rotation speed, indicating that the high shear stress produced by increasing screw rotation speed led to the chain scission and the mac- ro-radical, thus initiating the grafting reaction be- tween SEBS and MAH. The crosslinking reaction could be effectively suppressed through increasing screw rotation speed to prepare the functionalized product SEBS-g-MAH with higher percent of grafting （mass fraction 0.79% - 0. 89% ） and appropriate melt flow rate （ 1. 859 -4. 398 g/min） and lower gel content （no more than mass fraction 0.32% ） . Meanwhile, the toughening effect of SEBS-g-MAH on nylon （PA 66） was much better. The Izod not- ched impact strength of the blend reached up to 94 kJ/m^2, which was 30 times more than that of pure PA 66 without significant decrease of tensile and flexural strengthes.

关 键 词：苯乙烯-乙烯 丁烯-苯乙烯三嵌段聚合物 高剪切应力 马来酸酐 官能化 力学性能 结构形态 尼龙 

分 类 号：TQ330.1[化学工程—橡胶工业]