Macromolecular Engineering by Controlled/Living Radical Polymerization

技术概述可控/活性自由基聚合（CRP）是化学领域中发展最为迅速的领域之一。CRP是一种强大的合成技术，可以制备许多定义良好的大分子结构，并可用于生产新的特种材料。本提案的主要目的是探索几个分子结构参数对一系列新材料的形态和性能的影响，这些新材料是专门设计，制备和表征的，以扩展材料性能如何发展的知识。主要的智力挑战是精确控制分子结构，并确定链均匀性，组成或拓扑结构的缺陷将如何影响一些宏观性质。两个或两个以上不相容的单体将以统计、梯度、多段和块状的方式共聚；所得共聚物将被表征；他们的形态，以及他们的热机械和其他物理性质将被研究。可以产生具有高和低玻璃化转变温度的非晶聚合物的单体，也可以结晶的单体和可以形成两亲体系的单体将被使用。将确定星形嵌段共聚物中支链的影响和支链数对共聚物光谱性能的影响。新的密臂星型聚合物将被制备并详细分析合成过程的变化如何影响它们的结构和一些性质。合成具有较低临界溶解温度（LCST）的（Co）聚合物，并研究共聚物中单体的顺序分布和分子结构对LCST行为的影响。将评估具有各种可降解连接剂的模型聚合物的降解率，并将开发其结构与pH依赖性降解率之间的相关性。这些可降解单元将以可控的方式并入聚合物段，以制备可降解的乙烯基聚合物。本提案的结果将产生更广泛的影响，通过教育研究生、本科生和博士后，通过及时的出版物（包括“J. Chem”）传播本项目产生的信息。编辑”)，互联网和（国际）国家研讨会和CMU外展计划的演讲。由大约10家公司组成的CRP联盟将继续从NSF支持的活动中获得所有知识。拟议研究的影响将超出合成聚合物化学。它可以影响材料科学的基本概念，并导致一些有商业价值的材料的发展。

TECHNICAL SUMMARYControlled/Living Radical Polymerization (CRP) is among the most rapidly developing areas of chemistry. CRP is a powerful synthetic technique for preparation of many well-defined macromolecular structures and can be used to produce new specialty materials. The main objective of this proposal is to explore the effect of several molecular structural parameters on the morphology and properties of a range of new materials that were specifically designed, prepared and characterized to expand the knowledge of how the properties of material develop. The main intellectual challenge is to precisely control the molecular structure and also to determine how imperfections in chain uniformity, composition or topology will affect some macroscopic properties. Two or more incompatible monomers will be copolymerized in statistical, gradient, multisegmented and blocky ways; the resulting copolymers will be characterized; their morphology as well as their thermomechanical and other physical properties will be studied. Monomers which yield amorphous polymers with high and low glass transition temperature but also monomers which can crystallize and those which will form amphiphilic systems will be used. The effect of branching and the effect of the number of arms in star-block copolymers on the properties of a spectrum of copolymers will be cdetermined. New miktoarm star polymers will be prepared and analyzed in detail how variations in the synthetic procedure can affect their structure and some of their properties. (Co)polymers which exhibit lower critical solution temperature (LCST) will be synthesized and the effect of sequence distribution of monomers in the copolymer and molecular architecture on LCST behavior will be studied. The degradation rate of model polymers, with various degradable linkers, will be evaluated and a correlation between their structure and pH dependent degradation rate will be devloped. These degradable units will be incorporated into polymer segments in a controlled fashion to prepare degradable vinyl polymers. NON-TECHNICAL SUMMARYThe results from this proposal will generate broader impact by educating graduate, undergraduate students and postdoctoral fellows, by dissemination information generated in this project via timely publications (including "J. Chem. Ed."), internet and presentations at (inter)national symposia and CMU outreach programs. CRP Consortium with ~ 10 companies which benefit from all knowledge generated by NSF supported activities will be continued. The impact of the proposed research will extend beyond synthetic polymer chemistry. It could affect basic concepts in materials science and lead to the development of some commercially valuable materials.