Collaborative Research: Exploring the role of branching in determining the physicochemical properties of dendritic, hyperbranched and linear bis-MPA polyesters

合作研究：探索支化在确定树枝状、超支化和线性双-MPA聚酯的物理化学性质中的作用

• 批准号: 1807358
• 负责人: Scott Grayson
• 金额: $ 30万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807358&HistoricalAwards=false
• 关键词: Collaborative; Research; Exploring; role; branching

A significant percentage of the materials around us are made from plastics, also referred to as "polymers". The vast majority of synthetic polymers exhibit a linear structure, resembling a string, on the molecular level. Within the last few decades, a number of branched polymers, with a more tree-like molecular structure, have been designed and made commercially. The difference in structure from linear to branched results in unique properties and applications. Professor Grayson at Tulane University and Professor Nazarenko at the University of Southern Mississippi are using new synthetic methods to control the exact amount of branching in a family of polyesters. They study the properties of the polyesters to better understand how controlling polymer structure on the molecular level can yield polyesters with improved behavior and performance. This effort engages researchers from both the undergraduate and the graduate levels in a multi-disciplinary, collaborative approach. This project also include outreach to local public high school chemistry classes to demonstrate the use of the scientific method to better understand fundamental concepts in chemistry. A new interdisciplinary archeological chemistry course is also under development. With the support from the Macromolecular, Supramolecular and Nanochemistry Program from the Division of Chemistry, new synthetic tools are being employed to prepare a library of linear, hyperbranched, dendritic and "pseudodendritic" polymers based on the bis(hydromethyl)propanoic acid monomer. Both traditional (nuclear magnetic resonance) and more novel (mass spectrometry) characterization techniques are being utilized to elucidate the structure as well as the reactivity of each architectural class of these polymers. X-ray studies are combined with computer modeling to confirm the nature of the intra-and inter-molecular hydrogen bonding that occurs in these polyesters. Pressure-volume-temperature studies are carried out to understand the molecular packing in the melt and solid states. Finally, the materials dielectric properties are being investigated and correlated with the type of branching, as these materials show promise for high dielectric constant materials.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.

我们周围的材料中很大一部分是由塑料制成的，也称为“聚合物”。 绝大多数合成聚合物在分子水平上表现出类似于弦的线性结构。 在过去的几十年中，已经在商业上设计和制造了许多具有更树状分子结构的分支聚合物。 从线性到分支的结构差异导致独特的属性和应用。 杜兰大学（Tulane University）的格雷森（Grayson）教授和南密西西比大学（University of Southern Mississippi）的纳扎伦科（Nazarenko）教授正在使用新的合成方法来控制一个多植物家族中的确切分支。 他们研究了聚酯的特性，以更好地了解分子水平上的聚合物结构如何产生具有改善行为和性能的聚酯。 这项工作以多学科的协作方法来吸引本科和研究生级别的研究人员。 该项目还包括向当地公立高中化学课程进行宣传，以证明使用科学方法来更好地了解化学中的基本概念。新的跨学科考古化学课程也正在开发中。 在化学划分的大分子，超分子和纳米化学程序的支持下，正在使用新的合成工具来准备基于BIS（Hydromethyl）丙酸丙酸单体的线性，超支，树突状，树突状和“伪生型”聚合物的图书馆。 传统（核磁共振）和更多新颖的（质谱）表征技术都用于阐明这些聚合物的每个架构类别的结构以及反应性。 X射线研究与计算机建模相结合，以确认这些聚酯群体中发生的分子间和分子间氢键的性质。 进行压力 - 温度研究，以了解熔体和固态中的分子堆积。 最后，正在研究材料介电特性并与分支的类型相关，因为这些材料显示出对高介电恒定材料的希望。该奖项反映了NSF的法定任务，并且认为值得通过基金会的知识分子优点评估来支持支持，并具有更广泛的影响标准。

项目成果

Solution size variation of linear and dendritic bis-MPA analogs using DOSY- 1 H NMR

使用 DOSY- 1 H NMR 观察线性和树枝状双 MPA 类似物的溶液尺寸变化

• DOI: 10.1039/d0py01070g
• 发表时间: 2021
• 期刊: Polymer Chemistry
• 影响因子: 4.6
• 作者: Kareem, Oluwapelumi O.;Rahmani, Farzin;Hyman, Jason A.;Keller, Christopher B.;Pasquinelli, Melissa A.;Savin, Daniel A.;Grayson, Scott M.
• 通讯作者: Grayson, Scott M.

Selective monobenzylation of 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) to yield an AB linear monomer and analogous linear oligomers

2,2-双（羟甲基）丙酸（双-MPA）的选择性单苄基化产生 AB 线性单体和类似的线性低聚物

• DOI: 10.1016/j.tetlet.2020.152016
• 发表时间: 2020
• 期刊: Tetrahedron Letters
• 影响因子: 1.8
• 作者: Giesen, Joseph A.;Grayson, Scott M.
• 通讯作者: Grayson, Scott M.

Insights and comparison of structure–bulk property relationships in low generation hydroxylated polyester dendrimer and hyperbranched polymer prepared from bis-MPA monomer

• DOI: 10.1016/j.polymer.2021.124097
• 发表时间: 2021-08
• 期刊: Polymer
• 影响因子: 4.6
• 作者: Beibei Chen;M. Syed;Samantha P. Daymon;B. Olson;Oluwapelumi O. Kareem;Joseph A. Giesen;Gregory B. Fahs;R. R. Moore-R.;Scott M. Grayson;S. Nazarenko

Synthesis and Characterization of Linear, Homopolyester, Benzoyl-Protected Bis-MPA

苯甲酰保护的线性均聚酯双 MPA 的合成和表征

• DOI: 10.1021/acs.macromol.0c01045
• 发表时间: 2020
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Kareem, Oluwapelumi O.;Daymon, Samantha P.;Keller, Christopher B.;Chen, Beibei;Nazarenko, Sergei;Grayson, Scott M.
• 通讯作者: Grayson, Scott M.