Synthetic Approaches to Semi-Sequenced Copolymers

半序列共聚物的合成方法

• 批准号: 1709144
• 负责人: Tara Meyer
• 金额: $ 53万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-15 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1709144&HistoricalAwards=false
• 关键词: Synthetic; Approaches; Semi; Sequenced; Copolymers

Nature encodes properties into large molecules, like DNA and proteins, by combining a set of building block molecules, called monomers, into specific sequences. Spider silk protein, for example, derives its exceptionally tough nature from a specific sequence of amino acid monomers. This model for controlling properties in large molecules like polymers has been difficult to emulate in non-biological materials, however, because of the challenge in preparing perfectly sequenced molecules of this type. With the support from the NSF Macromolecular, Supramolecular and Nanochemistry Program, Professor Tara Meyer at the University of Pittsburgh conducts research to enhance our understanding of how precisely the sequence needs to be controlled to attain the desired polymer properties. This work is expected to have a significant impact scientifically, technologically, and educationally. The new synthesis method and the study of monomer sequence and their resultant properties represent a considerable scientific impact. The demonstration that sequence need not be perfect to be useful could translate into the increased use of sequence in industrially-produced polymers, a potential technological benefit. Finally, the involvement of graduate and undergraduate students in the research, with a particular emphasis on ensuring broad participation of trainees from all backgrounds, should contribute to a well-prepared scientific workforce.The Meyer group has successfully prepared perfectly sequenced, biodegradable, non-toxic polymers called poly(lactic-co-glycolic acids)s (PLGAs) and demonstrated the dependence of their properties on sequence. Unfortunately, the preparation of these perfectly sequenced PLGAs, and almost all other sequenced polymers, is too complicated and expensive to scale up for most applications. The research team thinks that one way to address this barrier is to answer the following two questions: "Is it essential to have a perfect sequence?" and "Is it possible that a polymer with a sequence pattern that is 75% correct would be almost as high performing as a polymer whose sequence is 100% correct?" The goal of this project is to address these questions by developing a new, more scalable method for preparing polymers with "just enough" sequence and then testing the properties of these semi-sequenced copolymers against perfect analogues. A new parallel/successive synthetic strategy is introduced and developed with the goal of creating semi-sequenced step-growth copolymers with an intermediate level of control over monomer order. Inspired by the classic synthesis of polyurethanes, the parallel/successive strategy involves the creation, in parallel, of compositionally controlled pre-oligomers with similar backbones but differing sequences. The successive reaction of these pre-oligomers produces semi-sequenced copolymers with a homogeneous composition in terms of the types of monomers present, but a segmented structure. Careful experimental design and the implementation of the method using a flow system can be implemented to yield materials with varying degrees of fine (monomer-by-monomer) and course (segment-level) sequence control. The comparison of the properties of the semi-sequenced copolymers with those of the perfectly sequence materials improves the understanding of the various mechanisms through which sequence effects manifest. Ultimately, this research may be translated into new technologies in advanced plastics and materials manufacturing.

大自然通过将一组称为单体的构建块分子组合成特定序列，将属性编码到大分子中，如DNA和蛋白质。 蜘蛛丝蛋白质，例如，从氨基酸单体的特定序列中获得其异常坚韧的性质。 然而，这种用于控制聚合物等大分子性质的模型很难在非生物材料中模拟，因为制备这种类型的完美测序分子的挑战。 在NSF大分子、超分子和纳米化学项目的支持下，匹兹堡大学的塔拉迈耶教授进行了研究，以提高我们对序列需要如何精确控制以获得所需聚合物性能的理解。 预计这项工作将在科学、技术和教育方面产生重大影响。 新的合成方法和单体序列及其所得性质的研究代表了相当大的科学影响。 序列不需要完美才有用的证明可以转化为在工业生产的聚合物中增加序列的使用，这是一个潜在的技术优势。 最后，研究生和本科生的参与，特别强调确保来自各种背景的受训者的广泛参与，应该有助于建立一支准备充分的科学工作者队伍。迈耶小组已经成功地制备了完美测序的、可生物降解的、无毒的聚合物，称为聚乳酸-乙醇酸共聚物（PLGA），并证明了它们的性质对序列的依赖性。 不幸的是，这些完美测序的PLGA和几乎所有其他测序聚合物的制备对于大多数应用来说太复杂和昂贵而无法扩大规模。 研究团队认为解决这一障碍的一种方法是回答以下两个问题：“拥有完美的序列是必要的吗？以及“有没有可能一个序列模式正确率为75%的聚合物与一个序列模式正确率为100%的聚合物具有同样高的性能？“该项目的目标是通过开发一种新的、更可扩展的方法来解决这些问题，该方法用于制备具有“刚好足够”序列的聚合物，然后测试这些半序列共聚物与完美类似物的性能。 一个新的并行/连续的合成策略的引入和开发的目标是创建半序列的逐步增长的共聚物与中间水平的控制单体顺序。受聚氨酯经典合成的启发，并行/连续策略涉及并行地产生具有相似主链但不同序列的组成受控的预低聚物。 这些预低聚物的连续反应产生半序列共聚物，就存在的单体类型而言，其组成均匀，但具有链段结构。仔细的实验设计和使用流动系统的方法的实施可以被实施以产生具有不同程度的精细（逐单体）和过程（片段水平）顺序控制的材料。 半序列共聚物与完全序列材料的性质的比较提高了对序列效应表现的各种机制的理解。 最终，这项研究可能会转化为先进塑料和材料制造的新技术。

项目成果

Property impact of common linker segments in sequence-controlled polyesters

• DOI: 10.1039/c8py01443d
• 发表时间: 2019
• 期刊: Polymer Chemistry
• 影响因子: 4.6
• 作者: Jordan H. Swisher;J. Nowalk;T. Meyer

Learning from Peptides To Access Functional Precision Polymer Sequences

• DOI: 10.1002/anie.201902217
• 发表时间: 2019-07-01
• 期刊: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
• 影响因子: 16.6
• 作者: Maron, Eva;Swisher, Jordan H.;Boerner, Hans G.
• 通讯作者: Boerner, Hans G.

Consequences of isolated critical monomer sequence errors for the hydrolysis behaviors of sequenced degradable polyesters

• DOI: 10.1039/c9py00891h
• 发表时间: 2019-09
• 期刊: Polymer Chemistry
• 影响因子: 4.6
• 作者: J. Nowalk;Jordan H. Swisher;T. Meyer

Short-Term and Long-Term Effects of POGIL in a Large-Enrollment General Chemistry Course

• DOI: 10.1021/acs.jchemed.9b01052
• 发表时间: 2020-05-12
• 期刊: JOURNAL OF CHEMICAL EDUCATION
• 影响因子: 3
• 作者: Vincent-Ruz, Paulette;Meyer, Tara;Schunn, Christian D.
• 通讯作者: Schunn, Christian D.

Influence of Short-Range Scrambling of Monomer Order on the Hydrolysis Behaviors of Sequenced Degradable Polyesters

• DOI: 10.1021/acs.macromol.9b00480
• 发表时间: 2019-06
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: J. Nowalk;Jordan H. Swisher;T. Meyer