本论文首先研究gemini表面活性剂辅助或未添加任何表面修饰剂条件下多壁碳纳米管（MWNTs）在多种有机溶剂中的解缠绕和分散性，在此基础上成功制备了一系列PS/MWNT和sPS/MWNT复合材料。另外，较深入地探讨了MWNTs对sPS的结晶行为的影响，并较系统地研究了PS/MWNT和sPS/MWNT复合材料的热稳定性能、导电性能和力学性能等。 主要研究内容和结果如下： 1、借助一种双子型表面活性剂（gemini表面活性剂）9BA-4-9BA促进MWNTs在甲苯中的分散。沉降实验、光学显微镜和TEM观察结果表明，9BA-4-9BA可以显著促进MWNTs的解缠绕，使其均匀分散于甲苯中。在此基础上，通过溶液复合法制备PS/MWNT复合材料，扫描电镜法（SEM）研究结果表明MWNTs在PS基体中的分散良好。通过对PS/9BA-4-9BA/MWNT复合材料中MWNTs对PS性能的研究表明，其导电性能相对于纯PS以及未添加9BA-4-9BA的PS/MWNT复合材料显著提高，热稳定性能相对于纯PS也有所提高，但力学性能没有明显改善。 2、沉降实验、光学显微镜和透射电镜法（TEM）观察结果表明，经过高速分散和超声处理后，MWNTs可以解缠绕并均匀分散在丙酮、二氯甲烷、THF和NMP中，并且在这四种体系中可以观察到明显的丁达尔效应，证明这些体系属于胶体分散系。 SEM观察表明，均匀分散的MWNTs-NMP体系经溶液复合制备的sPS/MWNT复合材料中，MWNTs分散良好。X-射线衍射（XRD）和差示扫描量热（DSC）测试结果表明，sPS及其复合材料在升温过程中均出现一个的晶相转变过程；在熔融结晶过程中，sPS/MWNT复合材料中sPS主要生成β晶，而sPS/9BA-4-9BA/MWNT复合材料在结晶过程中同时形成晶和β晶。与纯sPS相比，复合材料的结晶度有所降低。sPS/MWNT复合材料和sPS/9BA-4-9BA/MWNT复合材料的热稳定性能相对于纯sPS显著提高，导电性和弹性模量相对于纯sPS也有所提高。

Firstly, we studied the gemini surfactant-improved or pristine CNTs’ debundling and dispersion in various organic solvents. Then, a series of PS/MWNT and sPS/MWNT composites were fabricated based on the homogeneous dispersion of CNTs in the organic solvent. Finally, the crystallization behavior of sPS/MWNT composites, and the properties of PS/MWNT and sPS/MWNT composites were studied in detail. The main contents and the results of this thesis are listed in the following: 1. A gemini surfactant, 9BA-4-9BA, is employed to achieve homogeneous and stable dispersions of MWNTs in organic solvent and subsequent PS/9BA-4-9BA/MWNT composite. Sedimentation, optical microscopy and transmission electron microscopy (TEM) studies demonstrate that 9BA-4-9BA can greatly improve the dispersion and stabilization of MWNTs in toluene. Scanning electron microscopic (SEM) images clearly confirm the homogenous dispersion of individual MWNTs in PS. In addition, desired enhanced electrical property of the PS/9BA-4-9BA/MWNT composite relative to that of the neat PS and PS/MWNT composite is obtained. The thermal property of the composite is also enhanced relative to that of the neat PS, while the tensile property is not improved obviously. 2. Sedimentation, optical and TEM images clearly show that after high-shearing and ultrasonication, MWNTs can be debundled and dispersed in acetone, tetrahydrofuran (THF), dichloromethane and N-methyl-2-pyrrolodone (NMP). Additionally, the Tyndall effect suggests that the upper dispersions of MWNTs are colloidal systems rather than solutions. SEM images clearly confirm the homogenous dispersion of individual MWNTs in sPS/MWNT composites, which are prepared by solution-dispersion using the uniform dispersion of MWNTs in NMP. X-ray diffraction (XRD) and differential scanning calorimetric (DSC) studies show the occurrence of the  to  phase transition during the first heating process. In the cooling or melting crystallization process, sPS mainly forms β crystalline form in sPS/MWNT composite, while both  and β crystalline forms can be detected in sPS/9BA-4-9BA/MWNT composite. The composites have decreased crystallinities, however, enhanced thermal, electrical properties and tensile modulus relative to that of the neat sPS matrix.