接枝改性对芳纶纤维增强天然橡胶复合材料性能的影响

Grafting Modification of Aramid Fiber on Aramid Fiber Reinforced Natural Rubber Composites

采用氢氧化钾溶液对芳纶纤维(AF)表面进行处理,在此基础之上用环氧树脂/端羟基液体聚异戊二烯橡胶(EP/LIR)的甲苯溶液接枝纤维,将处理后的纤维、端羟基液体聚异戊二烯橡胶以及天然橡胶制成母炼胶,制备芳纶纤维增强天然橡胶复合材料。考察了纤维接枝的改性效果,以及KOH浓度、EP含量对复合材料力学性能的影响。红外光谱、扫描电镜、X射线能谱检测表明芳纶纤维接枝改性改善了纤维表面与复合物基体间的界面粘接,力学性能显示当KOH溶液的浓度为0.1%,EP含量为m(EP)/m(AF)=16.7/100时300%定伸应力和撕裂强度均有最优值。动态力学分析结果表明EP的加入会增大复合材料的储能模量和损耗模量,降低损耗因子峰值,从而提高了纤维与橡胶基体的界面粘合。

Aramid fiber（ AF） was grafted and coated with epoxy resin / hydroxyl-terminated liquid isoprene rubber（ EP/LIR） in toluene solution on the basis of aramid fiber treatment with KOH solution,then master batch was made by incorporating mixture of the modified fiber,LIR and natural rubber,after that,aramid fiber reinforced natural rubber composites were prepared. The effects of AF grafting modification,concentration of KOH,content of EP on mechanical properties of the composites were investigated. The results of FT-IR,SEM and EDS show that the grafting modification on aramid fiber makes the adhesive interface force between fiber surface and composite matrix prominent. Mechanical properties and DMA reveal that when the concentration of KOH is 0. 1% and m（ EP） / m（ AF） = 16. 7 /100,the stress at 300% elongation and tear strength show a optimal value,respectively. DMA reveal that AF / NR composites have higher storage modulus and loss modulus and lower peak of loss factor after addition with EP,implying that the interfacial adhesion is enhanced.