【作者】 魏小昕；

【导师】 张平则； 李淑琴；

【作者基本信息】 南京航空航天大学 ， 材料加工工程， 2009， 硕士

【摘要】 碳纳米管是一种新型的一维纳米材料,具有优异的力学性能,独特的微观结构,极大的长径比和比表面积,有望成为先进复合材料的理想增强体。但是碳纳米管本身容易团聚,这使得碳纳米管在聚合物中难以均匀分散,而且由于碳纳米管的表面惰性,使得碳纳米管与聚合物之间界面结合力较弱。这使得碳纳米管在复合材料中的应用受到一定的限制。为了解决这些问题,本论文通过对多壁碳纳米管进行表面改性处理,以改善碳纳米管在环氧树脂中的分散性以及和环氧树脂之间的界面结合力。并采用溶液混合法,制备了碳纳米管/环氧树脂复合材料。使用FT-IR、TEM、FE-SEM和万能材料拉伸机等仪器对材料的结构和性能进行了测试和表征,并分析了微观结构与性能之间的关系。结果表明:（1）在温和的反应条件下,酸处理(V_H2SO4/V_HNO3=3:1)可使无定型碳和催化剂等杂质去除,并且在不损坏碳纳米管结构的基础上使MWCNT表面产生羧基、羟基等活性基团。酸化处理后的碳纳米管经进一步酰胺化反应可在表面接枝三乙烯四胺,实现碳管的胺功能化。（2）采用等离子体处理方式对碳纳米管进行表面改性处理后,同样能够在碳纳米管表面接上羰基,胺基等活性基团,提高碳纳米管在环氧树脂中的分散性。（3）力学性能测试发现,加入原始碳纳米管对环氧树脂的力学性能的改善并不明显,且当含量大于0.75%后,环氧树脂的力学性能变差。而加入改性处理后的碳纳米管的环氧树脂的力学性能都有较大的提高。环氧树脂力学性能也与碳纳米管的含量相关,当加入原始碳纳米管及表面化学改性处理碳纳米管含量为0.75%时,碳纳米管/环氧树脂复合材料的力学性能最好。由于等离子体处理碳纳米管的分散性及与环氧树脂基体界面结合最好,因而加入等离子体处理碳纳米管的含量增加到1%时,复合材料的力学性能最好。更多还原

【Abstract】 Caron nanotubes(CNT) is a new one-dimensional nanometer material, it exhibit an excellent mechanical property: the super high tensile strength, toughness and Young’s modulus, and a unique microstructure: high specific surface area and high aspect ratio, which can be considered as an ideal reinforcement additive for advanced composites. However, the agglomeration of CNT into bundles results in poor CNT dispersion in polymer matrix, and the inactive surface of CNT makes weak interfacial bonding between polymer matrix and CNT. This makes the application of CNT in composites has been limited. To overcome these problems, in this paper, by modification the surface of MWCNT, to improve the dispersion of MWCNT in epoxy resin and the interfacial bonding between epoxy resin. MWCNT/epoxy resin composites were prepared using solution mixing method. The mechanical properties and the relationship between microstructure and properties of the composites were investigated by FT-IR、TEM、FE-SEM and tensile testing machine. The results indicated that:(1) Under mild reaction, acid solution (VH2SO4/VHNO3=3:1) could remove the impurities presented in the pristine MWCNT such as amorphous carbon and metal catalysts and produce carboxyl、hydroxylic groups on the surface of MWCNT without great damage to the structure of MWCNT. The surface of the MWCNT treated by acid could graft triethylene-tetramine(TETA) groups successfully by amidation route.(2)After modification the surface of MWCNT by plasma, it also can produce carbonyl、amidine groups on the surface of MWCNT. So as to improve the dispersion of MWCNT in epoxy resin and the interfacial bonding between epoxy resin.(3)From the result of the testing of mechanical properties, we can find that: When the pristine MWCNT added into the epoxy resin couldn’t improve the mechanical properties of epoxy resin obviously. And when the contents of the pristine MWCNT more than 0.75%, the mechanical properties of the epoxy resin were deteriorate. But when the MWCNT after modification added into epoxy resin it could improve the mechanical properties of the epoxy resin. The mechanical properties of epoxy resin also related with the contents of the MWCNT. When the contents of the pristine MWCNT and the surface chemical modification MWCNT reached 0.75%, the mechanical properties of the epoxy resin were the best. As the good dispersion in epoxy resin, and the better interfacial bonding with the epoxy, the contents of the MWCNT after plasma modification could reach 1%, At this point, the mechanical properties of the epoxy resin were the best.更多还原