【作者】 佘希林；

【导师】 宋国君；

【作者基本信息】 北京化工大学 ， 材料学， 2005， 博士

【摘要】 一维纳米材料,包括纳米线、纳米管、同轴纳米电缆等,因具有许多独特的光学、电学、磁学、化学等方面的性能,而成为近年来纳米材料领域的研究热点之一。聚合物纳米管是继碳纳米管之后又一个崭新的研究领域,正在异军崛起。本论文紧跟国际前沿,在大量检索、整理、综合分析文献的基础上,首次以孔径为200 nm阳极氧化铝(Anodic Aluminum Oxide,AAO)膜为模板、采用简单可行的模板浸润的物理技术,成功地组装了多种常规分子量的聚合物纳米管;并采用电化学沉积技术,首次成功地组装了常规聚合物包覆金属的同轴纳米电缆;分别对它们的结构与性能进行了表征,并首次对模板浸润法组装聚合物纳米管的机理进行了初步探讨。 1 聚合物纳米管 采用聚合物溶液和熔体浸润AAO模板的方法,组装了常规分子量的PS、PA6、PP、PA66、PU、PRSN—130、PCL和ABS等十多种聚合物纳米管和纳米线,并进行了结构与性能的表征。 (1)采用模板浸润法,首次在200 nm的AAO模板中组装了常规分子量聚苯乙烯(PS)纳米管。采用SEM、FESEM和TEM等测试表明:纳米管外径约为300 nm;当溶液浓度为2.5wt%,5.0wt%和10.0wt%时,制得的纳米管的管壁厚度分别为50 nm,70 nm和80 nm;在较更多还原

【Abstract】 One-dimensional nanomaterials, such as nanowire, nanotube and nanocable, have attracted increasing attention due to their novel optical, electronic, magnetic, chemical and good mechanical properties. Polymer nanotube is another heat point besides carbon nanotube. Various kinds of methods have been developed to prepare one-dimensional nanomaterials. Template method is proved to be very effective. In this thesis, the wetting template method, based on porous anodic aluminum oxide (AAO) membranes, has been used to fabricate several kinds of one-dimensional nanomaterials, including polymer nanotubes, metal nanowires and polymer enveloping metal coaxial nanocables. Their structures, properties have been characterized, and the mechanisms of difference methods have been tentatively studied. 1. Polymer nanotubesMore than 10 normal relative molecular mass polymer nanotubes and nanowires, such as PS, PA6, PP, PA66, PU, PRSN-130, PCL and ABS, etc., and their arrays were fabricated by simple physical techniques in the AAO templates with polymer solution and melt.(1) PS nanotubes with array was prepared by depositing a solution or melt of a high molecular weight PS (BASF) within the 200nm pores of anodic aluminum oxide (AAO). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM) were used to investigate their morphology and structures. These results illuminated that PS tubules weresuccessfully obtained and the wall thickness of PS nanotubes prepared by the 2.5wt%, 5.0wt% and 10.0wt% PS solution were respectively 50, 70 and 80 nm . The structure of polymer nanotubes depends strongly on the concentration of PS solution. The nanotubes made by 2.5wt% solution contain defects in its walls. Otherwise, the nanotubes by 5.0 wt% and 10.0 wt% solution are intact. The wall thickness of nanotubes from PS melt is about 110 nm. As to solution methods, the arrayed polymer nanotubes are easily prepared by the "down-to-up " wetting method, a simple solution wetting method.(2) The preparation of PA6, PP and PA66 nanotubes has not been reported. Template wetting method was, at the first time, applied to fabricate these nanotubes with polymer solution. PA6, PP and PA66 nanotubes and nanowires were, respectively, prepared at the different temperature. PP and LDPE nanotubes were successfully obtained by melt method. Based on the above result, the new viewpoint is raised that the polarity of polymer has much less influence on wetting process than the high surface energy of AAO template.(3) The bending modulus of polymer nanotubes was characterized by advanced AFM technique at the first time. PS nanotube’s bending modulus is 0.7 GPa.(4) PS, PA6 and PA66 nanotubes were characterized by TGA and DTA. The results indicated that polymer nanotubes have better anti-oxidation and anti-pyrogenation properties than their bulk polymer. In addition, polymer nanotubes have good anti-solvent properties.(5) Based on the results of testing properties, we can deduce that the array of the molecular chain in the wall of polymer nanotubes is different from normal bulk polymer. Further, it verifies the Martin’s conclusion that the polymer chains in the microcrystallites are oriented perpendicularly to the long axis of the nanotubes and the pore walls of the template.(6) At the first time, we put forward multi-layer wetting mechanism of polymer solution and critical value principle of polymer melt and drew its model graphs.2. Metal nanowiresPt, Fe and Au nanowires have been prepared by electrochemical deposition method.更多还原