Supramolecularly Templated Living REP-ROP Polymerizations and Block Copolymers

凯尔特艺术、童子军结、莫比乌斯带环和M.C.埃舍尔的艺术吸引了观众，并挑战了他们追踪连接起源的能力。一段时间以来，数学家们将环和具有可编程特性的循环重叠结构的拓扑结构描述为所谓的“结论”。在聚合物科学中，了解聚合物链缠绕的长度以及如何使这些缠绕的链溶解在溶液中可以产生具有有趣的物理性质和化学性质的新材料，可以扩展塑料，涂料，橡胶和复合材料的应用。在这个跨学科和实践性的领域，有很多培训和指导未来科学家的机会。这项研究有助于准备一个劳动力，解决复杂的问题和生产有价值的产品。本项目侧重于通过单体开环聚合（RO）和大引发环扩张聚合（REP）或REP- rop聚合设计和合成新的链链聚合物和嵌段共聚物组合物。利用结理论，可以获得各种结大分子，这些大分子具有可控的缠结以及具有高收率和高分子量的嵌段共聚物组成。螯合大分子的合成方法主要有：1)基于菲罗啉的大引发剂模板；2)原子转移自由基聚合方法衍生的均聚物和嵌段共聚物，以及具有原子转移自由基偶联的闭环；3)聚己内酯扩环策略；4)修饰侧基、控制链的组成和相互作用参数的聚合物反应。表征方法包括核磁共振波谱、MALDI质谱、原子力显微镜、排粒径色谱、流变学等，验证了聚合物在溶液和固体状态下的化学结构、拓扑结构和相分离。与聚合物物理学家、理论家和流变学家合作，利用链链聚合物的特性作为实际应用的材料和增容剂。

Celtic art, Boy Scout knots, Mobius strip rings, and M.C. Escher's art have fascinated the viewer and challenged their ability to trace the origin of connectivity. For some time now, mathematicians have described the topology of rings and cyclic overlapping structures with their programmable qualities into the so-called Knot Theory. In polymer science, understanding how long polymer chains become tangled and how to get those tangled chains to dissolve in a solution can result in new materials with interesting physical properties and chemical properties that can extend the applications of plastics, coatings, rubber, and composites. There are many opportunities for training and mentoring future scientists in this interdisciplinary and practical field. This research helps preparing a workforce that solves complex problems and produces valuable products. This project focuses on the design and synthesis of new catenated polymer and block copolymer compositions via monomer ring opening (RO) and macroinitiator ring expansion polymerizations (REP) or REP-ROP Polymerizations. By utilizing the Knot Theory, it may be possible to obtain various knotted macromolecules, which have controlled entanglements as well as block copolymer composition with high yields and high molecular weight. The approaches towards the synthesis of catenated macromolecules involve: 1) phenanthroline-based macroinitiator templates; 2) homopolymers and block copolymers derived from atom transfer radical polymerization methods and ring closures with atom transfer radical coupling; 3) ring expansion strategies with polycaprolactones; and 4) polymer reactions that modify the side groups and control the composition and interaction parameters of the chains. Characterization methods include nuclear magnetic resonance spectroscopy, MALDI mass sppectrometry, atomic force microscopy, size-exclusion chromatography, and rheometry, which verify the polymer's chemical structure, topology, and phase separation in solution and solid state. Collaborations with polymer physicists, theorists, and rheologists are pursued to harness the properties of the catenated polymers as materials and compatibilizers for practical applications.