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自制了邻苯二甲酰化壳聚糖、萘甲酰化壳聚糖、羧甲基化壳聚糖等3种壳聚糖衍生物对多壁碳纳米管(MWNTs)进行表面处理,发现邻苯二甲酰化壳聚糖(PhthCS)能有效提高MWNTs在极性6～10范围溶剂中的分散性及稳定性,并考察了PhthCS的分子量及浓度对MWNTs的分散性及稳定性的影响;通过微观形貌和元素分析,发现MWNTs部分表面包覆了一层厚度约为5～10 nm的包覆膜.经凝胶纺丝工艺制备了PhthCS-MWNTs/聚丙烯腈复合原丝,经预氧化、炭化制备了复合碳纤维,SEM结果表明PhthCS-MWNTs在复合原丝和复合碳纤维中分散均匀,良好取向;PhthCS-MWNTs对复合原丝和复合碳纤维的力学性能具有明显的改善作用,当PhthCS-MWNTs含量为0.5%时,复合碳纤维的拉伸强度提高了19.8%;增加PhthCS-MWNTs用量对复合碳纤维的拉伸模量具有显著提高,当PhthCS-MWNTs含量为3%时,复合碳纤维的杨氏模量从6.24 GPa提高到了13.86 GPa,增大了122%.
Three types of chitosan derivatives, such as phthaloylated chitosan, naphthoyl chitosan and carboxymethylated chitosan, were surface-treated with multi-walled carbon nanotubes (MWNTs) PhthCS can effectively improve the dispersibility and stability of MWNTs in solvents with the range of 6-10, and study the influence of molecular weight and concentration of PhthCS on the dispersibility and stability of MWNTs. Through the micro-morphology and elemental analysis, it was found that the MWNTs partially coated with a layer of coating thickness of about 5 ~ 10 nm PhthCS-MWNTs / polyacrylonitrile composite yarn prepared by the gel spinning process, pre- Oxidation and carbonization. The SEM results showed that PhthCS-MWNTs dispersed uniformly in the composite precursor and composite carbon fibers. PhthCS-MWNTs had a significant improvement on the mechanical properties of composite precursor and composite carbon fibers. When PhthCS- When the content of MWNTs was 0.5%, the tensile strength of the composite carbon fiber increased by 19.8%. The tensile modulus of the composite carbon fiber increased significantly when the amount of PhthCS-MWNTs was increased. When the content of PhthCS-MWNTs was 3% Modulus increased from 6.24 GPa to 13.86 GPa, increased 122%.