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。布泽尔的艺术吸引了观众，并挑战了他们追踪连通性起源的能力。一段时间以来，数学家们已经将环的拓扑和循环重叠结构及其可编程特性描述为所谓的纽结理论。 在聚合物科学中，了解聚合物链有多长以及如何使这些缠结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，这些材料可以扩展塑料，涂料，橡胶和复合材料的应用。在这一跨学科和实用领域，有许多培训和指导未来科学家的机会。 这项研究有助于培养一支能够解决复杂问题并生产有价值产品的劳动力。 该项目的重点是通过单体开环（RO）和大分子引发剂扩环聚合（REP）或REP-ROP聚合来设计和合成新的链状聚合物和嵌段共聚物组合物。通过利用纽结理论，可以获得具有受控缠结的各种打结的大分子以及具有高产率和高分子量的嵌段共聚物组成。合成链状大分子的方法包括：1）基于菲咯啉的大分子引发剂模板; 2）衍生自原子转移自由基聚合方法和具有原子转移自由基偶联的环闭合的均聚物和嵌段共聚物; 3）用聚己内酯的扩环策略;和4）改性侧基并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光谱法、MALDI质谱法、原子力显微镜、尺寸排阻色谱法和流变仪，其验证了聚合物的化学结构、拓扑结构和溶液和固体状态下的相分离。与聚合物物理学家，理论家和流变学家的合作被追求，以利用链状聚合物作为材料和增容剂的实际应用的性能。

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.