Organoborane Polymers in Catalysis and Supramolecular Materials Chemistry

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罗格斯大学纽瓦克分校化学系的Frieder Jaekle教授探索一类含有化学元素硼的新型聚合物的催化性能。 人造聚合物是由许多通过碳-碳键连接在一起的重复分子组成的塑料材料。 聚合物以许多不同的方式使我们的社会受益（例如，重量轻，易于制造，耐用），因此它们已成为日常生活的一部分。 聚合物科学领域的一个重要目标是生产易于回收的塑料材料-这包括在热或压力处理过程中重塑材料。 这项工作解决了与硼起始材料相关的一类独特的聚合物，而不是通常的碳基聚合物。 硼聚合物为“智能”材料的构建提供了优异的构建块，当暴露于外部刺激（如光、热、压力或化合物）时，这些材料会改变其原始特性。 它们可以提供比目前的碳基材料更可回收的塑料。 该项目有助于在高度跨学科的研究环境中培养多样化的学生群体。 Jaekle博士和他的团队参加了高中外展活动，并努力维护和扩大罗格斯-纽瓦克大学（PolyRUN）的聚合物和纳米材料表征设施。研究团队正在制备新的有机硼烷聚合物，研究其性能，并追求多样化的应用。 在第一个目标中，开发了聚合物刘易斯酸和“受挫”刘易斯对（FLP）作为负载型催化剂。 用可聚合基团改性定制的空间位阻但高度缺电子的三芳基硼烷，并使其与具有刘易斯碱基和/或促进聚合物回收的取代基的单体进行共聚。 研究了共聚物在亚胺、醛和酮的氢化和硅氢加成等无金属催化反应中的应用。 本工作的第二个目标集中在制备具有较少位阻的有机硼烷作为超分子材料的构建块的聚合物。当与刘易斯碱官能化的聚合物组合时，这些嵌段可逆地形成经典的刘易斯对作为瞬态聚合物网络的交联。 最后一个目标集中在有机硼烷聚合物的机械变色和刺激响应性能和聚苯乙烯的B-N类似物（氮杂硼杂环聚合物）的合成。 这项工作中的化学具有高度的变革性，具有产生具有新功能和广泛应用的新型材料的强大潜力。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With this award, the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry is funding Professor Frieder Jaekle of the Department of Chemistry at Rutgers University-Newark to explore catalytic properties of a new class of polymers that contain the chemical element boron. Artificial polymers are plastic materials consisting of many repeating molecules that are joined together by carbon-carbon bonds. Polymers benefit our society in many different ways (e.g., light-weight, easy to manufacture, and durable) and so they have become a part of everyday life. An important goal in the field of polymer science is to generate plastic materials that can be readily recycled - and this includes reshaping the materials during heat or pressure treatments. This work addresses a unique class of polymers associated with boron starting materials, instead of the usual carbon-based polymers. Boron polymers provide excellent building blocks for construction of 'smart' materials that change their original properties when exposed to external stimuli such as light, heat, pressure or chemical compounds. They may provide plastics that are more recyclable than current carbon-based materials. The project contributes to the training of a diverse group of students in a highly interdisciplinary research environment. Dr. Jaekle and his group participate in high school outreach activities and efforts at maintaining and expanding access to a polymer and nanomaterials characterization facility at Rutgers-Newark (PolyRUN).The research team is preparing new organoborane polymers, studying their properties, and pursuing diverse applications. In the first goal, polymeric Lewis acids and 'frustrated' Lewis pairs (FLPs) are developed as supported catalysts. Tailor-made and sterically hindered, yet highly electron-deficient, triarylboranes are modified with polymerizable groups and subjected to copolymerization with monomers that feature Lewis base groups and/or substituents that facilitate polymer recovery. The copolymers are investigated in metal-free catalysis reactions such as hydrogenation and hydrosilylation of imines, aldehydes and ketones. The second goal of this work focuses on the preparation of polymers with less sterically hindered organoboranes as building blocks for supramolecular materials. When combined with Lewis base-functionalized polymers, these blocks reversibly form classical Lewis pairs as crosslinks of transient polymer networks. The last goal concentrates on the mechanochromic and stimuli-responsive properties of organoborane polymers and the synthesis of B-N analogs of polystyrene (azaborine polymers). The chemistry in this work is highly transformative with a strong potential to lead to novel materials with new functions and a breadth of applications.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.