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

非技术总结本项目旨在研究电半导体聚合物分子的几何结构与其相应的材料性能之间的基本关系。大多数聚合物分子在纳米和亚纳米尺度上具有结构柔性，这导致了它们可以采用不同的3D形状。这种几何变化会影响对其应用非常重要的一系列聚合物性质，特别是与电子和光学性质相关的性质。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。这个职业项目通过合成分子来解决这个问题，分子在聚合物链上的不同链段之间具有可逆和可控的相互作用。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进行强制和破坏，从而由于分子形状可切换而产生定制的性质。这种结构控制的建立不仅能够获得改进的功能性能，而且还允许将聚合物材料可行地加工成与应用相关的形式。此外，从这个项目中获得的知识将促进对材料相关科学的基本理解，并有利于多个研究学科和STEM教育。该项目的教育部分侧重于通过实验室的相关实验和身临其境的学习体验，为学生连接科学概念和现实世界的个人知识。该项目的社会影响包括从科学出版物、新课程组成部分、教育软件以及为学术界和工业界培训的STEM学生中受益。技术总结该项目在功能聚合物材料的总体主题下整合了研究、教育和推广活动。通过结合化学合成、工艺工程和材料表征的协同方法，该研究项目试图在受控扭转构象和pi共轭体系的材料性质之间建立明确的基本关联。这一计划是由以下假设驱动的：对扭转构象的主动控制可以显著影响聚合物的性能和加工性。实现这一目标的关键策略是将可控的分子内动态键结合到聚合物主链中。在理论模拟和实验反馈的基础上，将为此类聚合物的合成和工艺工程制定一套系统的设计原则。这些材料的结构-性能关系将通过迭代的设计-测试-反馈-优化循环进行研究。最终目标是画出清晰的结构-性能关联，并建立设计原则，以适应共轭聚合物材料的综合性能。同时，计划开展教育和推广活动，以加强化学和广泛的STEM学习成果与研究计划的协同作用。教学重点是通过结合课程开发、本科生研究计划和外联活动的综合计划，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.