CAREER: Site-Differentiated Bimetallic Catalysts for Precise Polyolefin Synthesis

聚合物是当今使用最广泛的人造材料之一。它们的应用范围从普通塑料袋到救生医疗器械。目前用于制造聚合物的许多方法效率低、能源密集型和/或需要昂贵的原材料。为了促进更可持续的生产实践，Loi Do博士正在开发新的方法，直接从天然存在的和容易获得的原材料中制造聚合物。Do博士技术的关键是使用新的催化剂，这种催化剂控制原材料构建块如何连接形成聚合物。这项研究为社会提供了可以改善我们生活质量的新材料，从而造福社会。Do博士还积极参与了他在休斯顿大学(UH)的工业化学兴趣的外展活动。杜博士正在创建一些项目，让高中生和本科生有机会与专业科学家互动，并在日常生活中学习化学知识。Do博士鼓励学生在STEM领域追求职业生涯。杜博士还参与了对年轻化学家的动手实验室培训和指导，为他们成为下一代科学领袖做好准备。在化学系化学催化项目的资助下，休斯顿大学(UH)的Do博士正在开发新的可持续途径，以获得技术上有用的聚烯烃。这项研究旨在消除在制备中低密度聚乙烯时使用昂贵的α-烯烃共单体的必要性，并克服过渡金属催化剂容易被极性乙烯基烯烃抑制的倾向。Do博士的双金属催化剂利用金属-金属的协作性，实现了与传统单金属催化剂不同的反应模式。这些研究以机械研究为指导，使用光谱工具来询问可观察到的反应中间体的性质，并使用计算方法来评估离散反应步骤的能垒。这项工作对我们理解烯烃聚合催化至关重要，并可能为催化剂设计方面的改进提供见解。Do博士还发起了教育推广计划，将向年轻学生介绍化学专业。Do博士教育活动的目标是让公众能够学习化学，并为UH化学专业的学生提供在独立职业生涯中取得成功所需的实用技能。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Polymers are one of the most widely used man-made materials today. Their applications range from common plastic bags to life-saving medical devices. Many methods currently used to make polymers are inefficient, energy intensive, and/or require expensive raw materials. To promote more sustainable manufacturing practices, Dr. Loi Do is developing new ways to create polymers directly from naturally occurring and readily available raw materials. The key to Dr. Do's technology is the use of new catalysts that control how the raw material building blocks are connected to form polymers. This research benefits society by providing new materials that can improve our quality of life. Dr. Do is also actively involved in outreach activities that integrate his interests in industrial chemistry at the University of Houston (UH). Dr. Do is creating programs that give high school and undergraduate students the opportunity to interact with professional scientists and learn about chemistry in everyday life. Dr. Do excites students about pursuing careers in STEM fields. Dr. Do is also engaging in hands-on laboratory training and mentoring of young chemists to prepare them to become the next generation of scientific leaders. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Do at the University of Houston (UH) is developing new sustainable routes to access technologically useful polyolefins. This research seeks to eliminate the need to use expensive alpha olefin co-monomers in the preparation of low- and medium-density polyethylene and to overcome the tendency of transition metal catalysts to be inhibited by polar vinyl olefins. Dr. Do's bimetallic catalysts take advantage of metal-metal cooperativity to achieve reactivity patterns that are distinct from those of conventional monometallic catalysts. These studies are being guided by mechanistic investigations using spectroscopic tools to interrogate the nature of observable reaction intermediates and computational methods to evaluate the energy barriers of discrete reaction steps. This work is critical to our understanding of olefin polymerization catalysis and may provide insights into where catalyst design improvements could be made. Dr. Do is also initiating educational outreach plans that will introduce young students to the chemical profession. The objectives of Dr. Do's educational activities are to make learning chemistry accessible to the general public and give chemistry majors at UH the practical skills that they need to be successful in their independent careers.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.