RUI: Supramolecular main-chain liquid crystalline networks as a probe of mesogen formation and stability

RUI：超分子主链液晶网络作为介晶形成和稳定性的探针

• 批准号: 1105256
• 负责人: Kurt Wiegel
• 金额: $ 17万
• 依托单位: University of Wisconsin-Eau Claire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105256&HistoricalAwards=false
• 关键词: RUI; Supramolecular; main; chain; liquid

TECHNICAL SUMMARYInitial investigations funded by the Solid State and Materials Chemistry(SSMC) Program have indicated that the creation of supramolecular liquid crystalline networks produce materials with very interesting properties - simple one-ringed pyridyl systems produce networks that tie the reduction of liquid crystallinity in with statistical correlations of hydrogen bond acceptors. Similarly, more rigid groups allow for higher concentrations of disruptor inclusion. Non-macromolecular systems, created from simple 4-alkoxybenzoic acid groups retain liquid crystallinity at disruptor loadings above 99%. Continuation of funding from SSMC will allow for the development of new systems of varying functionality of the disrupting hydrogen bond acceptor groups (bis, tris and tetrakis), increasing rigidity and size of the hydrogen bond acceptor components (one ring pyridyl groups or longer, stilbazole structures). The study will include introduction of flexibility into all hydrogen bond accepting systems: ethyleneglycoxy chains for distonic, mesogen-forming acceptors (three, four and five) and alkyl chains (2, 4, 6 and 11 carbons) for increasing flexible netpoint creation. These systems will be studied using spectroscopic, thermal and x-ray analytical techniques. Special attention will be paid to the compositions of systems that only just eliminate liquid crystallinity, as these will be used as a probe for mesophase stability. The creation of these new liquid crystalline systems will provide valuable insight into the ability of a mesophase to stabilize in unfavorable, constrained (networked) conditions, providing 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. The results from this work will 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. Imparting new 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. NON TECHNICAL SUMMARYThis supported work will study the effects of reversible bonding on liquid crystalline polymers and networks. These materials will aid in understanding the effects of non-permanent linkages on the formation of materials important to the optical display industry. New visualization devices could be designed from the results of this work. Beyond the scientific impact of this project, activities will be used to enhance research infrastructure and give undergraduate students opportunities to carry out potentially industrially significant work. Over half of the student body at the University of Wisconsin- Eau Claire is low-income (11%) or first generation (41%) and about 60% are female, all of which are underrepresented in the scientific communities. According to the American Chemical Society UW-Eau Claire was recently ranked third nationally in the number of chemistry graduates -the highest of any Wisconsin college or university. Also, almost half of all UW- Eau Claire Chemistry undergraduates matriculate into graduate or professional programs. The research activities described will greatly enhance student training and intellectual development through hands-on experience with sophisticated techniques, equipment and the opportunities to develop their work for publication in professional journals and to present their findings at international meetings to an audience of the experts in the field.

技术概述由固态和材料化学（SSMC）计划资助的初步研究表明，超分子液晶网络的产生产生具有非常有趣的性质的材料-简单的单环吡啶基系统产生将液晶性的降低与氢键受体的统计相关性联系在一起的网络。类似地，更刚性的基团允许更高浓度的干扰物包含。由简单的4-烷氧基苯甲酸基团产生的非大分子体系在高于99%的破坏剂负载下保持液晶性。SSMC继续提供资金，将允许开发具有不同功能的破坏氢键受体基团（双，三和四）的新系统，增加氢键受体组分（一个环吡啶基或更长的，stilbazole结构）的刚性和尺寸。该研究将包括在所有氢键接受体系中引入灵活性：用于二阶、介晶形成受体（三、四和五个）的乙二醇氧基链和用于增加灵活网点产生的烷基链（2、4、6和11个碳）。这些系统将使用光谱，热和X射线分析技术进行研究。将特别注意仅消除液晶性的系统的组成，因为这些将用作中间相稳定性的探针。 这些新的液晶体系的产生将提供对中间相在不利的、受约束的（网络化的）条件下稳定的能力的有价值的洞察，提供对中间相形成的性质的洞察，以及对液晶形成中涉及的超分子力的量和强度的比较。这一研究成果将对超分子液晶领域产生广泛的影响。氢键介晶的应用受到缔合链结构脆弱性的限制。赋予超分子液晶系统新的特性将提供新的材料，结合共价物种的稳定性与氢键缔合链结构的不稳定性和愈合能力。非技术总结这项支持的工作将研究可逆键合对液晶聚合物和网络的影响。这些材料将有助于理解非永久性连接对光学显示器工业重要材料形成的影响。新的可视化设备可以设计从这项工作的结果。 除了这个项目的科学影响，活动将用于加强研究基础设施，并让本科生有机会开展潜在的工业重要工作。超过一半的学生在威斯康星州-欧克莱尔的大学是低收入（11%）或第一代（41%），约60%是女性，所有这些都是在科学界代表性不足。根据美国化学学会的数据，UW-Eau Claire最近在全国化学毕业生人数中排名第三，是威斯康星州所有学院或大学中最高的。此外，几乎一半的所有UW-欧克莱尔化学本科生进入研究生或专业课程。所述研究活动将大大加强学生的培训和智力发展，因为这些活动将使学生亲身体验先进的技术和设备，并有机会发展他们的工作，以便在专业杂志上发表，并在国际会议上向该领域的专家介绍他们的研究结果。