Advancing the Performance and Capabilities of Direct Arylation Polymerization (DArP)

有了这个奖项，化学系的大分子、超分子和纳米化学项目资助了巴里C。汤普森从南加州大学开发绿色和能源效率的方法来生产半导体聚合物。 这类现有的塑料电子材料在有机太阳能电池和发光二极管以及将光转换为电流的几种传感器应用中表现出了巨大的前景。 在这项工作中，半导体聚合物是使用基于廉价和丰富的元素，如铜和镍的催化剂制备的。 这些金属用于降低与聚合过程相关的能量势垒，使其更容易将起始材料转化为所需产物。 因此，它们的使用提高了半导体聚合物的可持续性，并使聚合物具有新的反应性和性能。 与该奖项相关的新方法提供了以几种不同的方式沿着聚合物主链组装重复单体单元沿着的方法，不仅产生由相同重复单元组成的线性链，而且产生其中这些重复单元不同并以受控和可预测的方式排列的链。 因此，在这些聚合物中获得这种先进的结构可能会导致其应用的改进，特别是它们将阳光转化为电能的效率。 这项工作使高分子化学的本科生和研究生得到了出色的培训，并扩展到了来自喜瑞都社区学院的南加州大学的学生。 通过与德国慕尼黑路德维希马克西米利安大学的研究生交流项目的发展产生的广泛影响对于帮助学生接触更广泛的国际研究和合作非常重要。本研究的重点是开发的替代合成路线，直接芳基化聚合的铜和镍配合物催化合成共轭，半导体聚合物。 还特别强调使用绿色和环境友好的溶剂。 直接芳基化聚合的能力通过专注于从逐步增长到链增长的过渡而扩展，这使得能够获得更先进的结构，如嵌段和梯度共聚物。 与直接芳基化聚合实现受控活性聚合的能力相关的研究是该研究领域的重要一步，因为它将能够控制分子量和聚合物多分散性。 另一个方向涉及探索用于相关的分解聚合方法的更可持续的氧化剂，其避免单体卤化和使用化学计量量的银氧化剂。 通过这项工作使用地球上丰富的铜和镍催化剂来获得共轭聚合物是重要的，并且具有显著降低用于共轭聚合物合成的现有程序的成本和复杂性的潜力，现有程序通常不是原子效率的，需要苛刻的反应条件，有毒溶剂，该奖项反映了NSF的法定使命，并通过使用基金会的智力价值进行评估，被认为值得支持和更广泛的影响审查标准。

With this award, the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry is funding Dr. Barry C. Thompson from the University of Southern California to develop green and energy efficient methods to produce semiconducting polymers. This existing class of plastic-electronic materials has shown great promise for use in organic solar cells and light emitting diodes, as well as several sensory applications in which light is converted to electrical current. In this work, semiconducting polymers are prepared using catalysts based on inexpensive and abundant elements such as copper and nickel. These metals are utilized to lower the energy barrier associated with polymerization processes, making it easier to convert starting materials to desired products. Consequently, their use improves the sustainability of semiconducting polymers and enables new reactivity and properties in the polymers. The new processes associated with this award provide means to assemble the repeating monomer units along main polymer chains in several different ways giving rise not only to linear chains composed of identical repeating units, but also chains in which those repeating units are different and arranged in controlled and predictable ways. Consequently, access to such advanced architectures in these polymers could lead to improvements in their applications, specifically the efficiency by which they convert sunlight into electricity. The work enables outstanding training for undergraduate and graduate students in polymer chemistry, extending to students hosted at the University of Southern California from Cerritos Community College. The broad impact through the development of a graduate student exchange program with Ludwig Maximillians University in Munich, Germany is very important for helping to expose students to the broader scope of international research and collaboration. This research is focused on the development of alternative synthetic routes to direct arylation polymerization catalyzed by copper and nickel complexes for the synthesis of conjugated, semiconducting polymers. Special emphasis is also placed on the use of green and environmentally friendly solvents. The capabilities of direct arylation polymerization are extended by focusing toward a transition from step-growth to chain-growth, which enables access to more advanced architectures such as block and gradient copolymers. Studies related to the ability of direct arylation polymerization to effect controlled living polymerization are a significant step forward in this area of research because it would enable control over the molecular weight and polymer polydispersity. An additional direction involves exploration of more sustainable oxidants for the related dehydrogenative polymerization process that avoids monomer halogenation and the use of stoichiometric amounts of silver oxidants. The use of earth-abundant copper and nickel catalysts to access conjugated polymers via this work is important and has the potential to significantly reduce the cost and complexity of existing procedures for conjugated polymer synthesis, which are generally not atom efficient, require harsh reaction conditions, toxic solvents, and create significant amounts of waste products.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.