Collaborative Research: Highly ordered concentric multilayer nanostructures with probable liquid crystalline features from rigid sphere-rod amphiphiles in solution

合作研究：溶液中刚性球棒两亲物具有可能液晶特征的高度有序同心多层纳米结构

• 批准号: 2215190
• 负责人: Tianbo Liu
• 金额: $ 51.86万
• 依托单位: University of Akron
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2215190&HistoricalAwards=false
• 关键词: Collaborative; Research; Highly; ordered; concentric

Non-technical Summary With support from the Solid State and Materials Chemistry program as well as the Condensed Matter Physics program, both in the Division of Materials Research, this project combines experimental and computational research and education aimed at advancing the fundamental understanding of how rigid block copolymers behave and self-organize in solution to liquid crystals. Liquid crystal is a state of matter between fluid liquids and solid crystals, and broadly used as display devices in TV screens (LCD), cell phones and contact lenses. Block copolymers are formed by linking two or more different long chain polymers together. Different blocks often possess different properties such as solubility, which lead block copolymers to self-organize into various nanometer-scale structures and make them important materials in drug delivery, coating and lubrication. While block copolymers with flexible chains have been well studied, those with fully rigid components are poorly understood. Investigators from the University of Akron and Kent State University design and study fully rigid block copolymers with special shapes for each block. This fundamental investigation enables the researchers to understand how these rigid copolymers behave in solution, what types of supramolecular structures they can self-organize into, and how the structure formations are controlled by temperature, solvent, as well as the shape and architecture of copolymers. The team focuses in particular on exploring the possible liquid crystal features emerging from such rigid block copolymer assemblies. The team examines a probable new type of liquid crystals formed by rigid block copolymers and their potential applications as materials through a series of experiments and complementary computer simulations. Furthermore, the project engages graduate students, undergraduate students through the NSF-REU center at the School of Polymer Science and Polymer Engineering at the University of Akron, and high school students from the Akron-Kent areas in Ohio. Graduate students from both institutions supported by this grant can expand their experience by mutual visits, collaborative experiments and discussions. The team also visits local schools that are serving large numbers of minorities and encourage students to take science courses and pursue careers in STEM.Technical SummarySupported by the Solid State and Materials Chemistry program as well as the Condensed Matter Physics program, both in the Division of Materials Research, Professors Liu and Tsige at University of Akron, along with Professor Lavrentovich at Kent State University, team up to explore the self-assembly of fully rigid, sphere-rod shaped amphiphilic block copolymers. Such rigid copolymers demonstrate completely different assembly behaviors from the well-studied flexible block copolymers, by forming uniform, onion-like, multilayer concentric assemblies with identical, well-defined inter-layer distance. The assemblies respond to the change of solvent polarity, temperature and others by changing the number of layers while maintaining the overall structure and inter-layer distance. The project includes the following objectives which are pursued by combining experimental characterizations and computer simulations: (1) investigation of the mechanism and driving forces of this novel onion-like assembly and the reason for the uniform assembly size; (2) elucidation of the rational control of their size (number of layers) via changing solvent, counterions or temperature; (3) studying the effects of rod length, rod number, sphere size/shape, and rod orientation on the self-assembly, and (4) determination whether these onion-like supramolecular structures possess liquid crystalline features, and if so, how these unique features impact liquid crystal science and technology. The research expands the fundamental understanding of block copolymer materials (from flexible ones to rigid ones) and liquid crystals, as well as their potential applications as functional materials.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

非技术摘要在固态和材料化学计划的支持以及凝聚态物理计划的支持下，无论是在材料研究部，该项目都结合了实验和计算研究和教育，旨在促进对刚性块共聚物如何在液晶溶液中表现出刚性块共聚物的基本理解。液晶是流体液体和固体晶体之间的物质状态，在电视屏幕（LCD），手机和隐形眼镜中广泛用作显示器。通过将两个或更多不同的长链聚合物连接在一起，形成块共聚物。不同的块通常具有不同的特性，例如溶解度，这些特性会导致共聚物自我组织成各种纳米尺度结构，并使它们成为药物输送，涂料和润滑的重要材料。虽然对具有柔性链的块共聚物进行了充分的研究，但具有完全刚性组件的组合物知之甚少。阿克伦大学和肯特州立大学设计和研究完全刚性的共聚物的研究人员，每个区块都有特殊的形状。这项基本研究使研究人员能够了解这些刚性共聚物在溶液中的行为，它们可以自我组织的哪种类型的超分子结构以及如何通过温度，溶剂，溶剂以及共聚物的形状和结构来控制结构的形成。该团队尤其专注于探索从这种刚性块共聚物组件中出现的液晶特征。该团队通过一系列实验和互补的计算机模拟来研究由刚性块共聚物及其作为材料的潜在应用形成的可能的新型液晶。此外，该项目通过聚合物科学与聚合物工程学院的NSF-REU中心与阿克伦大学的NSF-REU中心以及来自俄亥俄州阿克伦 - 肯特地区的高中生。来自这两个机构的两家机构的研究生都可以通过相互访问，协作实验和讨论来扩大他们的经验。 The team also visits local schools that are serving large numbers of minorities and encourage students to take science courses and pursue careers in STEM.Technical SummarySupported by the Solid State and Materials Chemistry program as well as the Condensed Matter Physics program, both in the Division of Materials Research, Professors Liu and Tsige at University of Akron, along with Professor Lavrentovich at Kent State University, team up to explore the self-assembly of fully rigid,球形杆形两亲块共聚物。这种刚性共聚物通过形成具有相同且定义明确的层间距离的均匀，类似洋葱的多层同心组件来表现出与良好的柔性块共聚物的完全不同的组装行为。组件通过更改层的数量，同时保持整体结构和层间距离，从而对溶剂极性，温度和其他人的变化做出反应。该项目包括通过结合实验表征和计算机模拟来追求的以下目标：（1）研究这种新型洋葱样装配的机制和驱动力，以及统一组装大小的原因； （2）通过改变溶剂，柜台或温度来阐明其大小（层数）的合理控制； （3）研究杆长，杆数，球体尺寸/形状和杆方向对自组装的影响，以及（4）确定这些类似洋葱的超分子结构是否具有液晶特征，如果是这样，这些独特特征如何影响液晶晶体晶体科学和技术。该研究扩展了对块共聚物材料（从柔性到刚性的材料）和液晶的基本了解，以及它们作为功能材料的潜在应用。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准通过评估来获得支持的。