CAS: Lewis Pair Catalyst Platform for Functional Polyether Synthesis

CAS：用于功能性聚醚合成的路易斯对催化剂平台

• 批准号: 2004167
• 负责人: Nathaniel Lynd
• 金额: $ 39.78万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004167&HistoricalAwards=false
• 关键词: CAS; Lewis; Pair; Catalyst; Platform

With this award, the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry is funding Professor Nathaniel Lynd of the Department of Chemistry at the University of Texas at Austin to develop new polymerization techniques for the controlled synthesis of polyethers. Polyethers are a class of large molecules in which every repeating unit contains a carbon-oxygen bond. They are typically prepared from small cyclic carbon-oxygen containing compounds called epoxides. This class of polymers is becoming increasingly important in today’s society because they are easier to degrade pathways than widely used plastics that contain mostly carbon-carbon bonds along the main polymer chains. Hence, polyethers might provide a viable solution to the recyclability problem which is of vital importance from an environmental perspective. In this research, catalysts based on aluminum are systematically designed to speed up the synthesis. The new chemical reactions are simple and can be transferred to laboratories around the world, which could greatly expand access to these types of polymers. This research is having a broader impact by providing education and research training to a diverse population of undergraduate and graduate students. Additional outreach efforts are focused on interactions with students from the Austin School for the Deaf and K-8 students through on-campus introductions to polymer chemistry at the Introduce a Girl to Engineering Day at the University of Texas-Austin. This research is focused on development of Lewis pair catalyst systems for functional polyether synthesis. There is currently no consensus polymerization technique available for polyethers that provides access to polymers with controlled molecular weights, chain-end functionality, good tolerance to monomer functionality, and availability to the non-specialist. This research seeks to further the development of such a tool by exploring the kinetics and mechanisms of the N-Al Lewis pair catalysts. Steric and electronic factors that govern Lewis-pair catalyst activity for epoxide polymerization are systematically explored. Detailed studies associated with Lewis pair formation and structure are also conducted. Special emphasis is placed on the investigation and elimination of parasitic initiation/termination through decomposition of a zwitterionic intermediate resulting in alkyl, or hydride terminal polymers, and/or undesirable cyclization. The methodology associated with this work introduces a readily available polymerization platform requiring only mixing of two commercially available chemicals. As such, it opens doors to new chemists with limited technical or infrastructural means to convert structurally diverse epoxides into functional and useful polymers.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.

通过该奖项，化学系的大分子，超分子和纳米化学计划是为德克萨斯大学奥斯汀分校化学系的纳撒尼尔·林恩（Nathaniel Lynd）提供资金，以开发新的聚合技术，以用于聚会者控制的合成。聚乙烯是一类大分子，每个重复单元都包含一个碳氧键。它们通常是由含有称为环氧化合物的化合物的小环氧氧中制备的。在当今社会中，这类聚合物变得越来越重要，因为它们比广泛使用的塑料更容易降解途径，而塑料主要含有主要聚合物链沿着主要的聚合物链。因此，聚乙烯可能会为可回收性问题提供可行的解决方案，从环境角度来看，这一点至关重要。在这项研究中，基于铝的催化剂是系统设计的，以加快合成。新的化学反应很简单，可以转移到世界各地的实验室，这可以大大扩展对这些类型的聚合物的访问。这项研究通过为本科生和研究生的多样性人群提供教育和研究培训，从而产生更大的影响。额外的外展工作集中在与奥斯汀学校的聋人和K-8学生的互动上，通过校园内的聚合物化学介绍在德克萨斯大学 - 奥斯汀大学的工程日介绍一个女孩。这项研究的重点是开发用于功能性聚醚合成的刘易斯对催化剂系统。目前尚无共有的聚合技术可用于提供对具有控制分子量的聚合物，链端功能，对单体功能的良好耐受性以及对非专家的可用性的聚合物的访问。这项研究旨在通过探索N-Al Lewis对催化剂的动力学和机制来进一步开发这种工具。系统地探索了控制环氧化物聚合的空间和电子因素。还进行了与刘易斯对形成和结构相关的详细研究。特别重点是通过分解寄生/终止的投资和消除，导致烷基或氢化物末端聚合物和/或不良环化的分解。与这项工作相关的方法引入了一个容易获得的聚合平台，仅需要两种市售化学品的混合。因此，它为具有有限的技术或基础设施的新化学家打开了大门，将结构上的环氧化物转化为功能和有用聚合物。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响审查标准通过评估来获得的支持。

项目成果

A guide to modern methods for poly(thio)ether synthesis using Earth-abundant metals

使用地球丰富的金属合成聚（硫）醚的现代方法指南

• DOI: 10.1039/d3cc03046f
• 发表时间: 2023
• 期刊: Chemical Communications
• 影响因子: 4.9
• 作者: Ferrier, Robert C.;Kumbhar, Gouree;Crum-Dacon, Shaylynn;Lynd, Nathaniel A.
• 通讯作者: Lynd, Nathaniel A.

Ionic Conductivity, Salt Partitioning, and Phase Separation in High-Dielectric Contrast Polyether Blends and Block Polymer Electrolytes

高介电对比聚醚共混物和嵌段聚合物电解质中的离子电导率、盐分配和相分离

• DOI: 10.1021/acs.macromol.2c02023
• 发表时间: 2023
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Zhu, Congzhi;Pedretti, Benjamin J.;Kuehster, Louise;Ganesan, Venkat;Sanoja, Gabriel E.;Lynd, Nathaniel A.
• 通讯作者: Lynd, Nathaniel A.

Structure–Property Relationships for Polyether-Based Electrolytes in the High-Dielectric-Constant Regime

高介电常数状态下聚醚基电解质的结构与性能关系

• DOI: 10.1021/acs.macromol.2c00639
• 发表时间: 2022
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Pedretti, Benjamin J.;Czarnecki, Natalie J.;Zhu, Congzhi;Imbrogno, Jennifer;Rivers, Frederick;Freeman, Benny D.;Ganesan, Venkat;Lynd, Nathaniel A.
• 通讯作者: Lynd, Nathaniel A.

Controlling Architecture and Mechanical Properties of Polyether Networks with Organoaluminum Catalysts

用有机铝催化剂控制聚醚网络的结构和机械性能

• DOI: 10.1021/acs.macromol.2c00602
• 发表时间: 2022
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Dookhith, Aaliyah Z.;Lynd, Nathaniel A.;Creton, Costantino;Sanoja, Gabriel E.
• 通讯作者: Sanoja, Gabriel E.