CNTs的表面改性及其在环氧树脂复合材料中的应用

摘要

The multi-walled carbon nanotubes (MWCNTs) were oxidized by the vitriolitric acid, and then modified silance coupling agent (KH560) treated with DOPO(9,10-dihydro-9-oxa-10-heteropoly philippine-10- oxide ) (DOPO-KH560) were used to modify the oxidized MWCNTs to obtain the chemical modified MWC NTs. Finally, we dispersed the modified carbon nanotubes into epoxy resin system to study the effect of modi- fied MWCNTs on the tensile properties of epoxy resins. The FT-IR experimental results indicated that the hy- droxyl and carboxy and the polymer chains were grafted to surface of carbon nanotubes. The results showed that the addition of carbon nanotubes in epoxy resin could effectively increase the toughness and strength of the epoxy resin. Moreover, the tensile strength and toughness of the epoxy resin composites were gradually increased by the addition of the original carbon nanotubes, oxide carbon nanotubes and the modified carbon nanotubes.%首先采用浓硫酸/浓硝酸对多壁碳纳米管（MWCNTs）进行混酸氧化处理,再将氧化后的CNTs与DOPO改性后的硅烷偶联剂（DOPO-KH560）进行改性,制备了DOPO-KH560表面化学修饰的MWC-NTs。在此基础上,将改性前后的CNTs分散在环氧树脂体系中,制成样条,研究了处理前后样条力学性能的变化。材料表面结构的红外光谱（FT-IR）分析表明,CNTs混酸氧化成功,表面成功引入了羟基和羧基,而且DOPO-KH560成功接枝到酸化CNTs上。材料微结构的透射电子显微镜（TEM）观察表明,酸化后MWCNTs被截短,分散性变好,接枝DOPO-KH560后CNTs表面包覆了一层低聚物。对处理后的样条进行力学性能测试并用扫描电镜（SEM）分析观察断面形态的变化。结果表明,环氧树脂中加入CNTs,能有效地增加环氧树脂的韧性和强度,且加入原CNTs、氧化CNTs、改性后的CNTs时增强增韧效果逐渐增加,加入最终CNTs后环氧树脂的增强增韧效果最明显。