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.

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德克萨斯大学奥斯汀分校化学系的Nathaniel Lynd教授开发用于聚醚可控合成的新聚合技术。 聚醚是一类大分子，其中每个重复单元都含有碳-氧键。 它们通常由称为环氧化物的小环状含碳-氧化合物制备。 这类聚合物在当今社会中变得越来越重要，因为它们比广泛使用的塑料更容易降解，这些塑料主要含有沿着主要聚合物链的碳-碳键。 因此，聚醚可能为可回收性问题提供可行的解决方案，从环境角度来看，这是至关重要的。 在本研究中，系统地设计了基于铝的催化剂以加速合成。 新的化学反应很简单，可以转移到世界各地的实验室，这可以大大扩大对这些类型的聚合物的访问。 这项研究通过为不同人群的本科生和研究生提供教育和研究培训，产生了更广泛的影响。 额外的推广工作的重点是通过在德克萨斯大学奥斯汀分校的“介绍女孩到工程日”活动上介绍聚合物化学，与奥斯汀聋人学校的学生和K-8学生进行互动。 本研究主要是开发用于功能性聚醚合成的刘易斯对催化剂体系。 目前没有可用于聚醚的共识聚合技术，其提供具有受控分子量、链端官能度、对单体官能度的良好耐受性以及非专业人员可用性的聚合物的途径。 本研究旨在通过探索N-Al刘易斯对催化剂的动力学和机理来进一步开发这样一种工具。 系统地探讨了影响路易斯对催化剂环氧化物聚合活性的空间和电子因素。 详细的研究与刘易斯对形成和结构也进行了。 特别强调的是放置在调查和消除寄生的起始/终止通过分解的两性离子中间体导致烷基，或氢化物末端聚合物，和/或不希望的环化。 与这项工作相关的方法引入了一个容易获得的聚合平台，只需要混合两种市售化学品。 因此，它为那些技术或基础设施有限的新化学家打开了大门，将结构多样的环氧化物转化为功能和有用的聚合物。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。

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.