CAREER: Conformational Control of pi-Conjugated Polymeric Materials through Dynamic Bonds.

非技术总结本项目旨在研究半导电聚合物分子的几何形状与其相应材料性质之间的基本相关性。 大多数聚合物分子在纳米和亚纳米尺度上具有结构柔性，这导致它们可以采用各种3D形状。这种几何可变性影响了广泛的聚合物性质，这些性质对于它们的应用是重要的，特别是与电子和光学性质相关的那些性质。然而，精确控制半导体聚合物的分子形状一直是一个长期存在的科学挑战。这个CAREER项目通过合成聚合物链沿着不同链段之间具有可逆和可控相互作用的分子来解决这个问题。通过这种方法，这些聚合物分子的平面化几何形状可以根据需要被强化和破坏，从而由于可切换的分子形状而导致定制的特性。这种结构控制的建立不仅可以实现改善的功能性能，而且还允许将聚合物材料可行地加工成应用相关的形式。此外，在该项目中获得的知识将促进对材料相关科学的基本理解，并使多个研究学科和STEM教育受益。该计划的教育部分侧重于通过实验室中的相关实验和沉浸式学习体验将科学概念与学生的真实个人知识联系起来。该项目的社会影响包括科学出版物、新课程内容、教育软件以及为学术界和工业界培训的STEM学生带来的好处。技术总结该项目将研究、教育和推广活动整合在功能聚合物材料的总体主题下。通过结合化学合成，工艺工程和材料表征的协同方法，该研究项目旨在建立π共轭系统的受控扭转构象和材料性能之间的明确基本相关性。该计划是由以下假设驱动的，即对扭转构象的主动控制可以显著影响聚合物性能和加工性能。 实现这一目标的关键策略是在聚合物主链中引入可控的分子内动态键。在理论模拟和实验反馈的基础上，将发展出一套系统的设计原则，用于此类聚合物的合成和工艺工程。这些材料的结构-性能关系将通过迭代设计-测试-反馈-优化循环进行研究。最终目标是绘制一个清晰的结构-性能相关性，并建立设计原则，定制共轭聚合物材料的综合性能。与此同时，计划开展教育和推广活动，以提高化学和广泛的STEM学习成果与研究计划的协同作用。教学重点是通过课程开发，本科研究计划和推广活动相结合的综合计划，为下一代STEM学生建立科学知识和现实生活经验之间的重要联系。

NON-TECHNICAL SUMMARYThis project aims to investigate the fundamental correlation between the geometry of electrically semiconducting polymer molecules and their corresponding materials properties. Most polymeric molecules possess structural flexibility at the nanometer and subnanometer scales, which leads to various 3D shapes that they can adopt. Such geometric variability impacts a wide range of polymer properties that are important for their applications, especially those related to electronic and optical properties. Precision control of the molecular shapes of semiconducting polymers, however, has been a long-standing scientific challenge. This CAREER project tackles this problem by synthesizing molecules with reversible and controllable interactions between different segments along the polymer chain. Through this approach, planarized geometries of these polymer molecules can be enforced and disrupted on demand, leading to tailored properties as a result of the switchable molecular shapes. Establishment of this structural control may not only enable the access of improved functional performance, but also allow for feasible processing of polymer materials into application-relevant forms. In addition, the knowledge gained in this project will advance fundamental understanding in materials-related sciences and benefit multiple research disciplines and STEM education. The educational component of this program focuses on connecting scientific concepts and real-world personal knowledge for the students through relevant experiments in the lab and immersive learning experiences. The societal impacts of this project include benefits from scientific publications, new course components, educational software, and trained STEM students for academia and industry.TECHNICAL SUMMARYThis program integrates research, education, and outreach activities under the overarching theme of functional polymer materials. Through a synergistic approach combining chemical synthesis, process engineering, and materials characterization, the research project seeks to establish clear fundamental correlations between controlled torsional conformation and materials properties of pi-conjugated systems. This plan is driven by the underlining hypothesis that active control over torsional conformation can significantly impact polymer properties and processability. The key strategy to achieve this objective is the incorporation of controllable intramolecular dynamic bonds into polymer backbones. A systematic design principle to the synthesis and process engineering of such polymers will be developed on the basis of theoretical simulations and experimental feedback. Structure-property relationships of these materials will be investigated through iterative design-test-feedback-optimization cycles. The ultimate goal is to draw a clear structure-property correlation and to establish design principles for tailoring the integrated properties of conjugated polymeric materials. In parallel, educational and outreach activities are planned to enhance chemistry and broad STEM learning outcome synergistically with the research program. The pedagogical focus is to make the essential connections between scientific knowledge and real-life experiences for the next generation of STEM students through an integrated plan combining course development, undergraduate research programs and outreach activities.