【作者】 杨杰；

【导师】 黄飞鹤；

【作者基本信息】 浙江大学 ， 化学， 2017， 博士

【摘要】 分子自组装指分子自发地(在氢键、静电、疏水亲脂作用、范德华力等弱作用力驱动下)构筑具有特殊结构和形状的稳定集合体的过程。在化学科学方面,超分子化学提供了新的观念、方法和途径来设计和制备自组装构筑基元,探索新颖的分子自组装手段,使得具有特定结构和基团的分子按照一定的方式自发地组装成所需的性质各异的超分子材料。主客体作用由于其固有的可逆性和适应性以及大环主体本身的特殊性,成为了一种非常重要的用来构筑超分子自组装体系的推动力。基于大环的超分子自组装是近年来研究的热点,多种基于大环主体的超分子自组装体系被广泛研究,如超分子两亲,超分子聚合物,超分子有机无机杂化材料等,并且已经应用在不同领域,如生物医学,材料科学,分析化学等。本论文主要基于大环主体-柱芳烃主客体识别体系来构筑各种刺激响应性的超分子自组装体系。论文主要包括以下五个部分:在第一部分工作中,我们利用偶氮苯桥连的柱芳烃二聚体作为主体,季铵盐衍生物作为客体构筑了线型超分子聚合物,并且用此柱芳烃二聚体交联季铵盐衍生化的聚丙烯酸甲酯,成功制备交联的超分子聚合物网络。结合氢谱、二维扩散排序谱图、粘度以及扫描电子显微镜,我们系统地证实了这种聚合物的形成。线性超分子聚合物的动态聚合/解聚合过程可以通过pH和光照两种方式来调节。更有意义的是,交联的超分子聚合物网络显示液晶性质,并且可以通过光照来改变,在光学领域存在很好的应用前景。在第二部分工作中,我们通过葫芦脲[8]主体增强的π-π作用构筑了基于水溶性柱[6]芳烃的超分子准聚轮烷,并且通过核磁和量热滴定证实了超分子聚合背后的自分类过程。这一方法克服了传统准聚轮烷制备效率低的缺点,为准聚轮烷的研究提供了新的思路,在制备超分子聚合物和其它超分子自组装体系方面具有借鉴意义。在第三部分工作中,我们报道了第一个阴离子水溶性柱[10]芳烃的制备,并系统研究了其和不同客体分子之间的主客体作用,为构筑基于水溶性柱[10]芳烃的超分子自组装体系提供了理论基础。此外,我们还基于水溶性柱[10]芳烃pH响应性主客体识别体系构筑了超分子两亲,研究了其刺激响应的可逆自组装。这种基于水溶性柱[10]芳烃的新的识别体系将有助于新的超分子功能化材料的制备,并且在不同的领域有潜在应用,例如超分子聚合物,纳米电子材料,药物传递和控制释放等。在第四部分工作中,我们成功构建了一个基于水溶性柱[6]芳烃主客体作用的紫外响应超分子两亲体系。通过简单的光照,我们可以方便的实现超分子组装体的形貌变化。此外,我们利用此超分子两亲体系在水相中实现多壁碳纳米管的分散,并且我们可以通过光控来实现碳纳米管的分散与聚集。这种新型的紫外响应的超分子两亲体系在药物控制释放、催化、纳电等领域具有很好的应用前景。在第五部分工作中,我们构筑了一个具有气体和光双重响应性的基于水溶性柱[6]芳烃和偶氮苯衍生物的主客体识别体系。此外,我们进一步利用此智能主客体识别体系构建可逆自组装的超分子两亲体系,实现双重响应的组装体的形貌控制。这种环境友好型的刺激响应性自组装行为提供一种新的可能性来实现"on demand"释放或者吸收各种化学物质如药物。由于二氧化碳和光对生物体至关重要,所以该合成的超分子自组装体系可以为仿生学的研究提供灵感。更多还原

【Abstract】 Molecular self-assembly refers to the process by which molecules spontaneously self-assembled to a stable state with special structures driven by weak forces such as hydrogen bondings,electrostatic interactions,hydrophobic effects,van der Waals forces,etc.In chemical science,supramolecular chemistry provides novel ideas and approaches to the design and preparation of self-assembly building blocks and to explore unique molecular self-assembly means,so that molecules with specific structures and groups could spontaneously assembled into the supramolecular materials with desired properties in a certain way.Host-guest interaction is a very important driving force for constructing supramolecular self-assembly systems because of its inherent reversibility and adaptability and the particularity of the macrocycilc hosts themselves.Macrocyclic host-based supramolecular self-assembly is a hot spot in recent years and various macrocyclic host-based supramolecular self-assembly systems have been widely studied,such as supramolecular amphiphiles,supramolecular polymer,supramolecular organic and inorganic hybrid materials,and further applied in different areas,such as biomedicine,materials science,analytical chemistry.In this thesis,we mainly focuse on the construction of a variety of functional self-assembly systems based on an emerging macrocyclic host-pillararene.The paper mainly includes these following five parts:In the first part,we prepared a novel linear supramolecular polymer and a supramolecular network based on the pillar[5]arene/secondary ammonium salt molecular recognition motif in CDCI3/CH3CN.The presence of an azobenzene moity acting as a molecular bridge and the pH-controlled reversible host-guest complexation played essential roles for the supramolecular polymer to show UV and pH-responsiveness,making it possible to achieve reversible polymer-oligomer and polymer-monomer transitions,respectively.More interestingly,the crosslinked supramolecular network exhibited liquid crystal property,and could be easily controlled by photo irradiation,bringing about lots of potential photonics applications.In the second part,we have developed an effective strategy to fabricate a linear supramolecular pseudopolyrotaxane with control and studied the mechanism behind the supramolecular polymerization,which can enrich the general self-sorting methodology to realize controllable supramolecular polymerization.This process prefers to accomplish selective recognition with larger numerical differences in the binding affinities among each interaction.We can foresee that our method has a tremendous potential in fabricating supramolecular polymers by different interactions with a variety of possible topologies.In the third part,we reported the first synthesis of water-soluble pillar[10]arene and the host-guest chemistry was fully investigated by kinds of methods.Furthermore,supramolecular amphiphiles based on these new host-guest systems were constructed,and their pH-responsive self-assembly in water were studied.These novel recognition motifs based on the water soluble pillar[10]arene in aqueous media will be helpful for the fabrication of functional architectures and definitely bring about many promising applications,such as supramolecular polymers,nanoelestronics,drug-delivery and controlled release.In the fourth part,we have successfully constructed a UV-responsive supra-amphiphile based on the host-guest complexation of a water-soluble pillar[6]arene.In contrast to the nanosheets formed by the amphiphilic guest itself,the supra-amphiphile self-assembled into nanorods.Upon irradiation with UV light,the transformation from nanorods to nanosheets was obtained.Furthermore,we applied this supramolecualr system in the photo-responsive dispersion of MWNTs into water.This new kind of supramolecular organic/inorganic hybrid material has numerous potential applications in many fields,including nanoelectronics,sensors and organic-inorganic hybrid materials.In the last part,a gas and photo dual-responsive host-guest recognition motif was established based on a water-soluble pillar[6]arene and an azobenzene derivative in an aqueous medium.This smart inclusion complex was further applied in the construction of a supra-amphiphile that could reversibly self-assemble into vesicles as a smart carrier for stimuli-responsive controlled release upon UV/vis irradiation or bubbling with N2/CO2.It is anticipated that utilizing green stimuli methods to realize unique self-assembly behavior in aqueous solution may offer new possibilities in "on demand" release or absorption of chemicals such as drugs.As both CO2 and light are crucial for living organisms,the system also provides inspiration for biomimicry by using synthetic supramolecular systems.更多还原