RUI: The Study of Multiple Hydrogen Bonds on Mesophase Structure and Stability

威斯康星大学欧克莱尔分校（University of Wisconsin-Eau Claire）材料研究部固态材料化学项目授予该RUI奖项，旨在研究新型液晶系统的创建，这将为利用多个氢键结合稳定中间相的能力提供有价值的见解。Wiegel教授在该领域的初步调查指出了本研究的三种理想体系：a)苯甲酸/吡啶结合（单氢键）；B)吡啶酮二聚体（双氢键）；c)亚胺/二氨基三嗪组合物（三氢键）。这些系统中的每一个都形成了一个强大的整体关联，并且在概念上具有线性和刚性，可以形成灾难性的、盘状的和香蕉状的液晶。为了研究各种介质形状和大小的影响，该项目将改变介质的刚性，以及尾部/间隔基团的灵活性和长度，并形成小分子（适用于每种介质类型）和聚合物（适用于灾难和香蕉介质）。这些系统将使用光谱、x射线和热分析技术进行研究。这个项目的结果有望提供对中间相形成的本质的洞察，以及对液晶形成过程中涉及的超分子力的数量和强度的比较。特别地，我们将学习当氢键数目增加时中间相是如何稳定的。此外，这些数据可能对超分子液晶领域产生广泛的影响。结合链结构的脆弱性限制了氢键介质的应用。了解中间相的稳定性作为氢键强度和多重性的函数可能对光学显示行业产生相当大的影响。多氢键聚合物和网络组合物表现出优于共价类似物的物理性质。将类似的特性赋予超分子液晶系统将提供新的材料，将共价体的稳定性与氢键结合链结构的稳定性和愈合能力结合起来。液晶在过去十年中成为最重要的光学材料之一，已成为科技界的支柱。利用非共价相互作用组装液晶材料提供了许多有趣的领域，包括活体聚合物系统和介质自愈能力。修复宏观结构缺陷。对每个缔合能形成一个、两个或三个氢键的液晶系统的研究，将有助于理解与缔合链结构的组装有关的液晶相的稳定性。此外，这项研究将用于加强研究基础设施，并支持威斯康星大学欧克莱尔分校的人力资源开发，这是一所低成本的公立机构，具有悠久的本科生/教师研究合作传统。该大学近一半的学生是来自低收入家庭的第一代学生，其中约60%是女性。所描述的研究活动可以通过对先进设备的亲身体验和在区域和国家会议上展示其研究成果的机会，大大加强学生的训练和智力发展。这些经验将是训练下一代科学家的宝贵步骤

This RUI award to University of Wisconsin-Eau Claire by the Solid State Materials Chemistry program in the Division of Materials Research is to study the creation of new liquid crystalline systems, which will provide valuable insight into the ability of a mesophase to stabilize using multiple hydrogen bonding associations. Initial investigations by Professor Wiegel in this field have pointed to three ideal systems for this study: a) benzoic acid/pyridine associations (single hydrogen bonds); b) pyridone dimers (double hydrogen bonds); and c) imide/diaminotriazine assemblies (triple hydrogen bonds). Each of these systems forms a strong overall association and conceptually possesses the linearity and rigidity to form calamitic, discotic and banana-shaped liquid crystals. In order to study the effects of various mesogenic shapes and sizes, the project will alter the rigidity of the mesogens, as well as the flexibility and length of the tails/spacer groups and forming both small molecules (for each of the mesogen types) and polymers (for the calamitic and banana mesogens). These systems will be studied using spectroscopic, X-ray and thermal analytical techniques. Results from this project are expected to provide insight into the nature of the formation of a mesophase, and a comparison of the quantity and strength of supramolecular forces involved in the formation of liquid crystals. In particular, we will learn how the mesophase is stabilized when the number of hydrogen bonds is increased. In addition, these data could have a broad impact on the field of supramolecular liquid crystals. The applications of hydrogen bonded mesogens are limited by the fragility of the associative chain structure. An understanding of the stability of a mesophase as a function of hydrogen bond strength and multiplicity could have considerable impact on the optical display industry. The multiple hydrogen bond polymer and network assembles have shown physical properties superior to their covalent analogs. Imparting similar characteristics to supramolecular liquid crystalline systems would provide new materials, combining the stabilities of covalent species with the lability and healing capabilities of hydrogen bonded associative chain structures. Liquid Crystals have become a mainstay of the scientific and technological community, emerging as one of the most important optical materials of the past decade. The assembly of liquid crystalline materials using non-covalent interactions offers many interesting areas involving living polymeric systems and the ability of the mesogens to self ?heal? and repair macroscale structural defects. A study of liquid-crystalline systems capable of forming one, two or three hydrogen bonds per association will lead to an understanding of the stability of liquid crystalline phases as related to the assembly of the associative chain structures. In addition, this research will be used to enhance research infrastructure and support human resource development at University of Wisconsin- Eau Claire, which is a low-cost public institution that has a long-established tradition of strong undergraduate/faculty research collaboration. Almost half of the students at the University are of first generation students from low-income families, and about 60% female. The research activities described could greatly enhance student training and intellectual development through hands-on experience with sophisticated equipment and the opportunity to present their findings at regional and national meeting. These experiences will be valuable steps in the training of the next generation of scientists