Collaborative Research: Syntheses and Solution-Phase Properties of Rigid Conjugated Ladder Polymer Chains

合作研究：刚性共轭梯形聚合物链的合成和溶液相性质

• 批准号: 2304969
• 负责人: Xiaodan Gu
• 金额: $ 35万
• 依托单位: University of Southern Mississippi
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2304969&HistoricalAwards=false
• 关键词: Collaborative; Research; Syntheses; Solution; Phase

With the support of the Macromolecular, Supramolecular and Nanochemistry program in the Division of Chemistry, Lei Fang of Texas A&M University and Xiaodan Gu of the University of Southern Mississippi are preparing and investigating solution-phase properties of rigid-rod conjugated ladder polymers. Conjugated polymers are a unique class of polymers with semiconducting properties resembling that of the chemical element silicon, unlike commonly used insulating polymers. They are extensively used in light emitting devices (LEDs), flexible electronics, sensors, biomedical imaging, and other applications that utilize the optoelectronic property of these polymeric materials. Conjugated ladder polymers, on the other hand, are a type of double stranded polymers with the bond connectivity resembling a ladder, so that the repeating units along the polymer main chain are all fused in the form of conjugated rings. Such a unique constitution imparts a conjugated ladder polymer with distinct polymer physics properties in comparison with conventional single stranded polymers. The studies associated with this project will focus on polymer-solvent interactions, single chain conformation, as well as chain diffusion dynamics in a series of conjugated ladder polymers that are soluble in common organic solvents. Additionally, synthetic methodologies will be developed to further gain control over polymer’s chain lengths and distribution of molar masses. This research has the potential to impact other fundamental scientific disciplines, including synthetic chemistry, polymer physics for semi-rigid polymers, biomacromolecules, polymer processing, and organic electronics. The education plan will focus on revitalizing and modernizing undergraduate chemistry curricula by implementing student-performed “Nobel Prize Reaction” experiments in undergraduate organic laboratory courses at both institutions. Professor Gu will additionally conduct extensive outreach activities among historically regional black colleges and universities in Mississippi via site visits and workshops.This research will aim to develop new fundamental understandings of the solution-phase properties of rigid-rod conjugated ladder polymers. The specific objectives will focus on (1) design and synthesis of defect-free conjugated ladder polymers that can be truly dissolved in organic solvents without aggregation, (2) understanding and quantification of polymer-solvent interaction and chain conformation of these model conjugated ladder polymers in solution, (3) development of controlled chain-growth polymerization methods based on catalyst transfer polymerization to synthesize conjugated ladder polymers featuring precisely tailored molar masses and narrow dispersity, and (4) establishing quantitative correlation between molar masses of conjugated ladder polymers with chain flexibility and diffusion dynamics. The combined collaborative efforts have the potential to advance fundamental knowledge of the synthetic chemistry and solution-phase polymer physics of rigid polymers and enable rational design principles for various applications of conjugated ladder polymers. These applications include organic field effect transistors, organic electrochemical transistors, actuators, electrochromic devices, photo detectors, and other optoelectronic devices.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.

在化学系高分子、超分子和纳米化学项目的支持下，德克萨斯农工大学的方磊和南密西西比大学的顾晓丹正在制备和研究刚性棒共轭梯形聚合物的溶液相性质。是一类独特的聚合物，其半导体特性类似于化学元素硅，与常用的绝缘聚合物不同，它们通常用于发光器件。另一方面，共轭梯形聚合物（LED）、柔性电子产品、传感器、生物医学成像和其他利用这些聚合物材料的光电特性的应用是一种双链聚合物，其键连接类似于梯子。沿着聚合物主链的重复单元均以共轭环的形式稠合，这种独特的结构赋予了共轭梯形聚合物与传统单链相比具有独特的聚合物物理性质。与该项目相关的研究将集中于聚合物-溶剂相互作用、单链构象以及一系列可溶于常见有机溶剂的共轭梯形聚合物中的链扩散动力学。控制聚合物的链长和摩尔质量的分布这项研究有可能影响其他基础科学学科，包括合成化学、半刚性聚合物的聚合物物理学、生物大分子、聚合物加工和有机电子学。该计划将重点通过在两个机构的本科有机实验室课程中实施学生进行的“诺贝尔奖反应”实验来振兴和现代化本科化学课程。顾教授还将通过实地考察在密西西比州历史悠久的地区黑人学院和大学中开展广泛的推广活动。这项研究旨在对刚性棒共轭梯形聚合物的溶液相性质产生新的基本理解，具体目标将集中在（1）设计和合成能够真正实现的无缺陷共轭梯形聚合物。溶解在有机溶剂中而不聚集，（2）了解和量化溶液中这些模型共轭梯聚合物的聚合物-溶剂相互作用和链构象，（3）开发基于催化剂转移聚合的受控链增长聚合方法来合成共轭梯具有精确定制的摩尔质量和窄分散性的聚合物，以及（4）建立具有链柔性和扩散动力学的共轭梯形聚合物的摩尔质量之间的定量相关性，共同的协作努力有可能推进合成的基础知识。刚性聚合物的化学和溶液相聚合物物理，并为共轭梯形聚合物的各种应用提供合理的设计原理，这些应用包括有机场效应晶体管、有机电化学晶体管、执行器、电致变色器件、光电探测器和其他光电器件。通过使用基金会的智力价值和更广泛的影响审查标准进行评估，NSF 的法定使命被认为值得支持。