【作者】 徐鹏；

【导师】 姜世梅； 沈家骢；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2008， 博士

【摘要】 近年来,嵌段共聚物自组装结构的研究倍受人们关注,同时,利用自组装嵌段共聚物制备各种不同形态及有序结构的功能纳米材料和纳米结构材料也成为了目前研究的热点。然而,利用嵌段共聚物对纳米粒子的聚集结构的调控以及对制得的纳米粒子的进一步研究还比较少。本论文的主体思想是利用嵌段共聚物制备出纳米粒子,一方面对纳米粒子的聚集形貌进行调控,另一方面结合纳米粒子的特性拓展其应用。本论文开展了以下几个方面的工作:1.对两亲性嵌段共聚物PS-b-P2VP和PCMA-b-P2VP在溶液中的自组装结构以及胶束薄膜的形貌进行了研究,为进一步制备纳米粒子提供了基础。2.基于PS-b-P2VP,制备出了金属铼配合物的纳米颗粒和CdS纳米粒子,利用PS链段和P2VP链段对溶剂亲和性的差异,通过调节溶剂环境,实现了对纳米粒子聚集结构的调控。3.分别利用PS-b-P2VP和PCMA-b-P2VP的胶束结构制备基底表面支持的Au、Ag纳米粒子阵列,并结合微接触印刷方法(μCP),实现对金属纳米粒子聚集体更大尺度(微米级)上的控制,制备出多尺度图案化的金属纳米粒子阵列。4.为了进一步拓展制备出的规整结构纳米粒子的应用。我们利用嵌段共聚物胶束制备出氧化铁纳米粒子,并结合铁纳米粒子对碳纳米管生长的催化特性,实现了碳纳米管在催化剂基底上的可控生长,并结合其它一些处理手段,制备出了图案化的高定向性碳纳米管。更多还原

【Abstract】 The self-assembling micelles of amphiphilic block copolymers and their applications in fabricating nanoparticles are among the hottest topics of polymer science. This thesis focuses on the behaviors of amphiphilic block copolymers in dilute solutions and thin films, including the effects of solvent nature and solution concentration on the self-assembly of two amphiphilic block copolymers. The micelles are used as nanoreactors to fabricate some metal nanoparticles and semiconductor nanoparticles, the size and the aggregates of the nanoparticles in the micelles have been controlled in our experiments. In addition, the nanoreactors of micelles, combined with microcontact printing (μCP), have been successfully in fabricating patterned metal arrays and carbon nanotubes.First, we systematically investigated the effects of the solvent nature and solution concentration on the self-assembling behaviors of two amphiphilic block copolymers (PS-b-P2VP and PCMA-b-P2VP). The affinity of the solvent to different blocks seriously affected the solubility and self-assembly of the block copolymers. In some solvents, which were preferential affinity to a specific block, the block copolymer can self-assemble into nanometer-sized spheral micelles consisting of a soluble corona and an insoluble core. By spin-coating the solution of micelles onto the substrates, after evaporating the solvent, the thin films with regular morphologies of nanodots remained on the substrates. Due to the different solubility of the block chains, the thin films from the micelles show sensitivity to the solvent atmosphere around them. Dipping the films in a solvent, which was selective to the core blocks, with the swollen of the core blocks, the surface of the thin films transformed from the nanodots to nanoporous.The micelles from amphiphilic block copolymer PS-b-P2VP and PCMA-b-P2VP used as nanoreactors have been succeed in fabricating Au, Ag, CdS nanoparticles. To the block copolymers, the pyridine ligands in the micelles either in the core parts or in the corona parts can be easily incorporated with some metal ions or proton, so the nanoparticles can be selectively located in the core parts or corona parts. In addition, the reversion of the block copolymer micelles endues the tunable morphologies of the aggregations of nanoparticles. The aggregations of Au nanoparticles and CdS nanoparticles in the micelles of PS-b-P2VP can be transformed from core-embedded to corona-embedded. We also attached Rhenium complex, a luminescence molecule, to the PS-b-P2VP chains. The resulting polymer metal complexes were able to form micelles in different solvent systems, and the emissive complexes tagged on the block copolymers can act as luminescent probes in the resulting micelles.To obtain Au nanoparticles, four methods were introduced to our system. In the colloid solution, beside NaBH4, pyrrole was used as an effective reducing agent, the formed Au nanoparticles and Au-polypyrrole compound haved been investigated. In order to generate periodically ordered Au nanopartiles, thermal decompension and oxygen plasma were used as effective reducing procedures, but the obtained Au nanoparticles show great different in the scale to these two methods.Taking advantage of the nanoreactors of amphiphilic block copolymers, we introduced a simple, convenient, and versatile approach for fabricating arrays of gold, silver nanoparticle aggregates of various sizes by combining them with the method of microcontact printing (μCP).Moreover, Fe nanoparticles were fabricated in our system by the same way, which have been successfully used as templates to fabricate carbon nanotubes in a PECVD system. Besides the intensity and scale of the carbon nanotubes could easily controlled, with the introducing ofμCP, patterned carbon nanotubes successfully fabricated on the substrates. In addition, with the pre-coating of the substrate with a layer of Al2O3 and changing the size of catalysts, patterned and aligned carbon nanotubes were successfully fabricated in our system.更多还原