碳纳米管-有机化蒙脱土多维纳米界面构筑及其对环氧树脂的增韧机制

分别采用混酸、环氧树脂（EP）和硅烷偶联剂对碳纳米管（CNTs）进行功能化处理，用十八烷基三甲基氯化铵对蒙脱土（MMT）进行有机化处理，将具有一维纳米尺度的CNTs和二维纳米尺度的有机化蒙脱土（OMMT）复合引入EP酸酐固化体系，通过溶液共混法制备纳米OMMT/EP、CNTs/EP、CNTs-OMMT/EP复合材料。使用简支梁冲击试验仪测试三种复合材料的冲击强度，并利用SEM观察纳米复合材料的冲击断面形貌。实验结果表明，当OMMT的含量为4wt%时，纳米OMMT/EP复合材料的冲击强度比未掺杂纳米组分的EP提高了16.7%。经硅烷偶联剂处理后的CNTs（Si-CNTs）能与EP基体形成良好界面，当Si-CNTs的含量为0.9wt%时，纳米Si-CNTs/EP复合材料冲击强度比未掺杂纳米组分的EP提高了84.0%。当OMMT的含量为4wt%、Si-CNTs的含量为0.9wt%时，纳米Si-CNTs-OMMT/EP复合材料的冲击强度比未掺杂纳米组分的EP提高了135.4%。管状CNTs和片层结构OMMT对EP的韧性具有协同提高作用。

Formation of interface and toughening mechanism of carbon nanotubes-organic montmorillonite/epoxy resin composites

Carbon nanotubes (CNTs) were respectively treated by mixed acid, epoxy resin (EP) and silane coupling agent. Montmorillonite (MMT) was modified by eighteen alkyl three methyl ammonium chloride. CNTs and organic montmorillonite (OMMT) were placed in EP cured by anhydride. Nano OMMT/EP, CNTs/EP and CNTs-OMMT/EP composites were prepared by method of solution blending. The impact strength of the three kinds of was tested by Charpy impact tester. The impact profile of the nano CNTs/EP, OMMT/EP and CNTs-OMMT/EP composites were observed by scanning electron microscopy. The experimental results show that when the mass fraction of OMMT is 4wt%, the impact strength of OMMT/EP composites is 16.7% higher than that of the pure EP. The interface between Si-CNTs and EP cured by anhydride is strong. When the mass fraction of Si-CNTs is 0.9wt%, the impact strength of Si-CNTs/EP composites is 84.0% higher than that of the pure EP. When the mass fraction of OMMT is 4wt% and the mass fraction of CNTs is 0.9wt%, the impact strength of Si-CNTs-OMMT/EP composites is 135.4% higher than that of the pure EP. CNTs and OMMT can synergistically enhance the toughness of EP.