碳纳米管/超支化重氮盐自组装膜的制备及性能研究

利用静电吸附自组装技术将酸化处理后的单壁碳纳米管(SWNTs)与超支化重氮盐(DAS)组装成多层膜.利用紫外光谱、椭偏仪、原子力显微镜、扫描电镜、拉曼光谱等对自组装膜的生长过程、膜厚增长、自组装膜表面形貌以及纳米管在膜中的存在状态等进行了检测,并利用纳米压痕仪测试了自组装膜的硬度和弹性模量.研究结果表明,SWNTs与DAS不仅发生了静电吸附,而且还发生了化学交联.同时碳纳米管均匀分散在自组装膜中.这两种因素的共同作用使得自组装膜表现出良好的纳米力学性能,硬度达到2.0GPa左右,弹性模量达到10.0GPa左右,而且可以从基底上剥离下来成为独立支撑膜.

FABRICATION AND PROPERTIES OF SINGLE WALL CARBON NANOTUBES AND HYPERBRANCHED DIAZONIUM SALT SELF-ASSEMBLY MULTILAYERS

Acid treated single-wall carbon nanotubes(SWNTs)were fabricated into multilayers with a hyperbranched polymer of diazonium salt(DAS)using the layer-by-layer electrostatic adsorption technique.The fabrication process,multilayer thickness variation,multilayer surface morphology and the interaction between SWNTs and DAS were detected by UV-Vis absorption spectroscopy,ellipsometry,atomic force microscopy,scanning electron microscopy and Raman spectroscopy,respectively.Moreover,the nanomechanical properties of the multilayer film was measured by nanoindentation.All results show that SWNTs and DAS can be fabricated into multilayers based on the cooperation of electrostatic attraction and chemical cross-linkage between SWNTs and DAS.Further,this cooperation endows the SWNTs/DAS multilayer films with outstanding nanomechanical properties.Their hardness and modulus may be as high as 2.0 GPa and 10.0 GPa,respectively.Finally,the SWNTs/DAS multilayer film can be peeled off from the substrate as a free-standing membrane.