Nanostructured block copolymer gel electrolytes based on polyethers

该项目的目标是设计用于聚合物电池和双电层电容器的电解液的纳米结构嵌段共聚聚合物凝胶。这些材料还具有自我修复特性，由此设计的纳米结构还能够在机械损伤后恢复功能特性。为此，两亲性聚醚基ABC三嵌段三元共聚物将与(共价)可交联块A(用于Diels-Alder反应的呋喃部分或用于铜催化叠氮-炔化学的炔类)一起使用，B块可溶于提供离子迁移率的有机和水溶液(如聚甲基缩水甘油醚)，而C块携带带电重复单元用于基于羧基和氨基结合的可逆(非共价)交联或替代地，两性离子共单体。然后在水介质中自组装将导致核-壳-电晕胶束，其中核形成块A可以通过共价键进行交联以进一步增强纳米结构的形状，而C块允许基于静电吸引进行进一步的交联；这里，在C块中携带例如阴离子羧基的ABC三嵌段三元共聚胶束打算与在C块中类似地具有阳离子氨基的拮抗胶束结合。这些离子相互作用一方面可能导致形成一个确定的网络或凝胶，另一方面它们的动态性质将成为所需的自我修复机制的基础。此外，中间的B嵌段将使离子能够通过凝胶扩散，在损伤之前和愈合后应确保在可比较的水平上。合成将使用相应缩水甘油醚单体(即A嵌段的呋喃或炔基缩水甘油醚，例如B嵌段的甲基缩水甘油醚，C嵌段的烯丙基缩水甘油醚)的顺序活性阴离子聚合的组合，然后使用硫醇-烯化学对C嵌段进行侧链修饰，以实现带电的重复单元。表征将在这个项目中发挥重要作用，从对ABC三嵌段三元共聚物的全面分析到各自凝胶的制备，除了形态研究外，还包括研究交联效率和探索稳定性。此外，对于离子的扩散，应该准确地了解凝胶的功能，即离子的导电性，以评估最终的自愈进展。最后，凝胶电解液将用于测试电池，作为新电解液材料的原理证明。

The goal of this project is to design nanostructured block copolymer gels for use as electrolytes in polymer-based batteries and electric double-layer capacitors. These materials also feature self-healing properties, whereby the designed nanostructure additionally enables the restoration of the functional properties after mechanical damage. For this purpose, amphiphilic polyether-based ABC triblock terpolymers will be utilized with a (covalently) crosslinkable block A (furfuryl moieties for Diels-Alder reactions or alkynes for copper-catalyzed azide-alkyne chemistry), a block B being soluble in both organic and aqueous electrolytes providing ion mobility (e.g., poly(methyl glycidyl ether)), and a block C carrying charged repeating units for reversible (non-covalent) crosslinks based on combinations of carboxyl and amino moieties or alternatively, zwitterionic comonomers. Self-assembly in aqueous media will then lead to core-shell-corona micelles, wherein the core-forming block A can be crosslinked to further enhance the nanostructured shape by covalent bonds whereas the C block allows for further crosslinks based on electrostatic attractions; here, an ABC triblock terpolymer micelle carrying, for example, anionic carboxyl moieties in the C block is intended to be combined with the antagonistic micelles, which analogously possess cationic amino groups in the C block. These ionic interactions might on the one hand lead to the formation of a defined network or gel, and on the other their dynamic nature will be the basis for the desired self-healing mechanism. Furthermore, the middle B block will enable the diffusion of ions through the gel, which should be ensured at a comparable level before damage and after healing.The synthesis will be accomplished using a combination of sequential living anionic polymerization of the respective glycidyl ether monomers (i.e. furfuryl or alkynyl glycidyl ether for block A, e.g., methyl glycidyl ether for block B, allyl glycidyl ether ether for block C) followed by side chain modification of the C block using thiol-ene click chemistry to realize the charged repeating units. The characterization will play an important role in this project starting from the comprehensive analysis of the ABC triblock terpolymers towards the preparation of the respective gels, including investigations of crosslinking efficiencies and probing the stability besides morphological studies. Furthermore, the functionality, i.e. the ionic conductivity, of the gels should be precisely understood with regard to the diffusion of ions, to evaluate the self-healing progress in the end. Finally, the gel electrolytes will be used in test batteries as proof-of-principle for new electrolyte materials.