CAREER: Developing New Polymer Supported Catalysts with High School, Undergraduate, and Graduate Students

在这个由化学系化学催化项目（CAT）资助的项目中，Sam Houston州立大学（SHSU）的Christopher Hobbs教授与本科生和研究生合作开发新的可回收化学催化剂。化学催化剂能加快化学反应的速度。催化剂通常用于制备塑料和药品等重要材料。为了避免使用金属元素所带来的高成本和环境问题，人们希望制造具有长寿命的催化剂。在这项研究中，聚合物支撑（“塑料骨架”）用于从反应中回收催化剂，使其可以重复使用。根据聚合物载体的不同，开发了不同的分离策略。霍布斯教授和他的学生开发的聚合物支撑催化剂具有“相选择性”，与油从水中分离的原理大致相同，因此在促进化学反应后，它们会从产物中分离出来。这种绿色化学方法避免了浪费和耗时的净化步骤。此计划的教育方面，旨在透过开发新的实验课程，以及让本科生亲身参与研究实验室，扩大上海外国语大学高分子科学教育的范围。额外的社会效益包括招募和参与研究项目的弱势学生（高中、本科生和研究生），以及在温德姆学区（Windham school District）担任数学和科学导师的志愿者工作，温德姆学区是德克萨斯州刑事司法部门（TDJC）的公立学校系统。Hobbs教授和他的学生开发了新的聚合物支持的配体和催化剂，这些配体和催化剂是非极性和相选择性可溶的。这些聚合物负载催化剂采用开环复分解聚合（ROMP）、无环二烯复分解聚合（ADMET）和原子转移自由基聚合（ATRP）的组合制备。这些都是对聚合物结构提供高水平控制的技术。该项目的具体目标是聚合物支持的salen， n -杂环碳（NHC）和n -杂环基配体和催化剂。Hobbs教授正在进一步准备阶段选择性单链纳米颗粒（SCNP）和单分子配体/引发剂系统（ULIS）支持催化剂的第一个例子。由于它们的非极性选择性，这些催化剂可以在简单的液/液分离条件下回收和再循环，从而避免了色谱纯化。清除和回收的能力减少了溶剂浪费，并突出了该项目作为绿色和可持续化学模型的意义。这项工作的更广泛影响包括从代表性不足的群体中招募学生从事STEM（科学、技术、工程和数学）职业，以及促进针对德克萨斯州刑事司法部（TDJC）系统中被监禁的个人的外展和志愿服务。该奖项反映了美国国家科学基金会的法定使命，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。

In this project funded by the Chemical Catalysis Program (CAT) of the Division of Chemistry (CHE), Professor Christopher Hobbs of Sam Houston State University (SHSU) works with undergraduate and graduate students to develop new and recyclable chemical catalysts. Chemical catalysts increase the speed of chemical reactions. Catalysts are commonly used for preparing important materials such as plastics and medicines. It is desirable to make catalysts with long lives to avoid the high costs and environmental problems associated with the metallic elements that are often used. In this research, polymers supports ("plastic backbones") are used to recover a catalyst from a reaction so it can be re-used. Varied separation strategies are developed, depending on the polymer support. In much the same way that oil separates from water, the polymer-supported catalysts developed by Professor Hobbs and his students are "phase-selective" so they physically separate from the products after facilitating a chemical reaction. This green chemistry approach avoids wasteful and time-consuming purification steps. Educational aspects of this project are aimed at broadening the scope of polymer science education at SHSU through the development of new experiments for laboratory courses as well as hands-on participation in the research lab by undergraduates. Additional societal benefits include the recruitment and participation of under-represented students (high school, undergraduate, and graduate) in research projects and volunteer work as math and science tutors in the Windham School District, the public-school system for those incarcerated in the Texas Department of Criminal Justice (TDJC).Professor Hobbs and his students develop new polymer-supported ligands and catalysts which are nonpolar and phase-selectively soluble. These polymer-supported catalysts are prepared using a combination of ring opening metathesis polymerization (ROMP), acyclic diene metathesis (ADMET) polymerization, and atom transfer radical polymerization (ATRP). These are all techniques that offer high levels of control over polymer architecture. Specific goals of the project target polymer-supported salen, N-heterocyclic carbene (NHC), and N-heterocycle-based ligands and catalysts. Professor Hobbs is further preparing the first examples of phase-selective single chain nanoparticle (SCNP) and unimolecular ligand/initiator system (ULIS) supported catalysts. Because of their non-polar phase selectivity, these catalysts may be recovered and recycled under simple liquid/liquid separation conditions, thus avoiding chromatographic purifications. The ability to remove and recycle diminishes solvent waste and highlights the implications of this project as a model for green and sustainable chemistry. Broader impacts of this work include recruitment of students from under-represented groups to STEM (science, technology, engineering and mathematics) careers, as well as promoting outreach and volunteerism aimed at individuals who are incarcerated in the Texas Department of Criminal Justice (TDJC) System.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.