采用硝酸氧化法制备氧化多壁碳纳米管(MWNTs-COOH),在其表面引入羧基.以对甲苯磺酸(PTSA)为催化剂、二甲亚砜(DMSO)为溶剂,采用羟丙基-β-环糊精(HP-β-CD)修饰MWNTs-COOH,制备了分散性较好的羟丙基-β-环糊精-多壁碳纳米管 (HP-β-CD-g-MWNTs)复合材料.经透射电镜(TEM)、傅里叶变换红外光谱(FT-IR)、热重分析(TGA)等测试后表明,HP-β-CD被成功接枝到多壁碳纳米管(MWNTs)表面.分散性研究结果表明,HP-β-CD-g-MWNTs复合材料在水溶液中的分散能力达到2.3mg/mL,这一属性使得该材料有望成为医学材料或药物载体材料.采用紫外-可见(UV-Vis)吸收光谱法研究扁桃酸与HP-β-CD-g-MWNTs复合材料的相互作用,结果表明扁桃酸可能通过π-π堆积、极性相互作用及氢键吸附在复合材料表面.基于上述分子间作用力的形成,与碳纳米管作用的分子可望实现从碳纳米管表面得到控制释放或缓释.

Carboxyl groups are oxidized by nitric acid and introduced onto multi-walled carbon nanotubes (MWNTs). Catalyzed by ptoluenesulfonic acid (PTSA), the oxidized MWNTs (MWNTs-COOH) are reacted with hydroxypropyl-β-cyclodextrin (HP-β-CD) to obtain HP-β-CD-g-MWNTs with good dispersivity. The prepared composites are fully characterized by Transmission Electron Microscopy (TEM), Fourier Transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA), the results indicate that HP-β-CD is successfully grafted onto MWNTs. The dispersion performance test indicates that HP-β-CD-g-MWNTs are well-dispersed in the aqueous solutions, thus the composites are able to find their potential applications in biomedical materials or drug deliveries. The interactions between HP-β-CD-g-MWNTs and mandelic acid are investigated by using Ultraviolet-Visible light (Uv-Vis) absorption spectrum. The results indicate that mandelic acid is adsorbed on the surface of HP-β-CD-g-MWNTs by conjunct interactions, such as π-π stacking, polar interaction, and hydrogen bonding. Due to the molecular interactions, the absorbed molecules are able to realize controlled-releasing or sustained-releasing from the surface of MWNTs.