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Synthesis and characterization of liquid-crystalline supramolecular architecture by a combination of molecular recognition and polymerization reaction.

机译：分子识别和聚合反应相结合的液晶超分子结构的合成和表征。

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In nature, self-assembly with well defined shapes obtained from combinations of polymeric building blocks with complex architecture are abundant since they are responsible for the production of structural materials and for the generation of some of the most efficient mechanisms. One of the many roles liquid crystallinity plays in natural systems is in their self-assembly and organization. The assembly of these complex natural systems is largely under thermodynamic control which is manipulated by their liquid crystallinity. The goal of this thesis is to use Nature as a model for the development of new synthetic concepts and strategies in the field of polymer science. The two models selected are rod-like and icosahedral viruses. The strategy involved in this thesis requires the design of libraries of monodendritic building blocks with well defined flat tapered and conical shapes which self-assemble into cylindrical and respectively spherical shapes. By analogy with viruses these supermolecules will generated hexagonal columnar and spherical cubic thermotropic phases. These liquid crystalline phases allow the determination of their shape by X-ray diffraction and Scanning Force Microscopy. Libraries of flat tapered and conical monodendritic building blocks will be functionalized with polymerizable groups and polymerized to generate the first examples of polymers of cylindrical and spherical shapes with diameter and length, and diameter controlled at the nanoscale level. The organization of these dendritic monomers in a liquid crystalline assembly is also used to aggregate their polymerizable groups in a reactor of artificially enhanced concentration and restricted geometry during the polymerization process and therefore, generate a new approach to the control of polymerization. The resulting liquid crystallinity provides access to the thermodynamically controlled assembly and characterization of these newly developed polymers. With few exceptions, there is no precedent for polymers with controlled cylindrical and spherical shapes which assemble into thermotropic liquid crystalline phase. The molecular design, synthesis, characterization and polymerization of these bulky monomers and polymers requires a combination of supramolecular chemistry, liquid crystallinity and polymer science. This thesis will provide an entry into the design of visualizable polymeric materials with dramatically different properties which are determined by their shape. Cylindrical and spherical polymers obtained from flexible backbones jacketed with dendritic coats will access a mechanism to control the conformation and rigidity of their flexible chains. The rigidity of cylindrical polymers can be manipulated via their diameter, internal structure and conformational restrictions. Mechanisms to change in a reversible and controlled way to change the shape of the polymer from rod-like to spherical is elaborated and this work can open a new technological concepts in areas such as fibers, films, membranes, electronic, photonic and controlled release systems.
机译：从本质上讲，通过将复杂结构的聚合物结构单元组合而成的具有明确定义形状的自组装是丰富的，因为它们负责结构材料的生产和某些最有效机制的产生。液晶性在自然系统中发挥的众多作用之一是它们的自组装和组织。这些复杂的自然系统的组装在很大程度上受热力学控制，而热力学由其液晶性控制。本文的目的是使用自然作为模型来发展高分子科学领域中新的合成概念和策略。选择的两个模型是棒状病毒和二十面体病毒。本文涉及的策略要求设计具有明确定义的扁平渐缩形和圆锥形形状的单树突状构建体的库，这些形状可自组装成圆柱状和球形。与病毒类比，这些超分子将产生六方柱状和球形立方热致变相。这些液晶相可通过X射线衍射和扫描力显微镜确定其形状。平坦的锥形和圆锥形单树枝状结构单元的库将通过可聚合的基团进行功能​​化，并进行聚合，以生成直径和长度以及直径控制在纳米级别的圆柱形和球形聚合物的第一个示例。这些树枝状单体在液晶组件中的组织也用于在聚合过程中在人工提高浓度和限制几何形状的反应器中聚集其可聚合基团，因此产生了控制聚合的新方法。所得的液晶度提供了对这些新开发的聚合物进行热力学控制的组装和表征的途径。除少数例外，没有任何先例可控制组装成热致液晶相的圆柱形和球形聚合物。这些庞大的单体和聚合物的分子设计，合成，表征和聚合需要超分子化学，液晶性和聚合物科学的结合。本论文将为可视化聚合物材料的设计提供一个入口，该材料具有明显不同的特性，这些特性由其形状决定。从带有树枝状涂层的柔性骨架获得的圆柱形和球形聚合物将获得一种机制来控制其柔性链的构象和刚性。圆柱形聚合物的刚性可以通过其直径，内部结构和构象限制来控制。阐述了以可逆和可控方式将聚合物的形状从棒状变为球形的机制，这项工作可以在纤维，薄膜，膜，电子，光子和控释系统等领域开启新的技术概念。

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