Determination of Fundamental Structure-Topology-Morphology-Properties for Naturally-derived Recyclable Polymer Materials Designed to Address Environmental and Societal Challenges

第一部分：非技术性总结全球塑料污染问题正处于关键时刻。聚合物材料(塑料)在日常产品中影响社会，促进安全、健康和福利，也有利于美观、快乐和便利。虽然有些塑料材料应该是耐用的并具有长期稳定性(例如轮胎、汽车塑料部件、头盔等)，但在初始设计阶段应考虑整个聚合物生命周期，以便在材料的功能完成后纳入可回收机制。塑料堆积和持久性对环境的负面影响正变得越来越重要。这项工作的预期广泛影响将是天然衍生聚合物材料的发展，这些材料的设计具有复杂性，使其能够展示独特的性能，并具有用于其解聚和回收的内置机制。重点将是构建具有高吸水性和韧性的水凝胶材料，并将进行严格的研究，以确定聚合物材料的有效性，以满足与全球水资源挑战相关的需求，以及减少摩擦、生物污垢和结冰的技术挑战。这项工作的重大成果预计将是未来几代科学家的先进知识和认识，他们将考虑他们开发的技术的整个生命周期。第2部分：技术总结总体目标是开展基础研究，以加深对二元共价和非共价(超分子)交联聚合物材料的组成-结构-拓扑-形态效应的理解，并有兴趣开发机械坚固的功能聚合物，这些聚合物来自天然原料，设计用于各种应用，展示水凝胶、防污、防结冰、污染物隔离和其他行为，以应对社会挑战，同时还可以回收，以限制材料长期对环境的不利影响。葡萄糖将作为构建复杂拓扑结构的滑环聚合物网络的主要构件，具有共价和超分子相互作用，从而产生动态的、机械性能良好的水凝胶行为，并进一步扩展到具有高吸水性和高孔隙率的聚合物高内相乳液(PolyHIPE)材料。将进行基础研究以确定完整材料的性能，然后调查它们基于有意解聚的可回收性和长期水解性降解性。假设系统地研究结合了共价键、超分子主客体相互作用、滑环拓扑和聚HIPE形态的网络将增强对composition-structure-topology-morphology-properties关系的基本理解，并导致能够具有超高吸水性动力学和容量的先进材料，同时表现出动态的、响应的物理化学和力学行为，具有广泛的应用前景。重要的是，将开发用自然来源的原料和内置的解聚和分解路线来制造此类材料的技术，以提高可持续性和可回收性。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

PART 1: NON-TECHNICAL SUMMARYThe global plastics pollution problem is at a critical point. Polymer materials (plastics) impact society in everyday products that facilitate safety, health and welfare, and also beauty, pleasure and convenience. Although some plastic materials are meant to be durable and possess long-term stability (e.g. tires, plastic parts for automobiles, helmets, etc.), the full polymer life cycle should be considered during the initial design stages, to incorporate mechanisms for recyclability once the function of the material has been completed. The negative environmental effects of plastic accumulation and persistence are becoming of increasing importance. The expected broad impact of this work will be in the advancement of naturally-derived polymer materials that are designed to possess complexities that allow for them to exhibit unique properties, and have in-built mechanisms for their depolymerization and recycling. A focus will be upon constructing the materials to behave as super-absorbent and tough hydrogels, and rigorous studies will be conducted to determine the effectiveness of the polymer materials to meet needs associated with global water resource challenges, and technological challenges of reducing friction, biofouling, and ice formation. Significant outcomes of this work are expected to be an advanced knowledge and awareness by future generations of scientists who will consider the full life cycle of the technologies that they develop. PART 2: TECHNICAL SUMMARYThe overall objective is to conduct fundamental studies that lead to advanced understanding of the composition-structure-topology-morphology effects for dual covalently and non-covalently (supramolecularly) crosslinked polymer materials, with an interest in developing mechanically-robust functional polymers that are derived from natural feedstocks and designed to exhibit hydrogel, anti-fouling, anti-icing, pollutant sequestering and other behaviors for diverse applications that address societal challenges, while also being recyclable to limit adverse environmental impacts of the materials long-term. Glucose will serve as the primary building block from which topologically-complex slide-ring polymer networks will be constructed, having both covalent and supramolecular interactions to result in dynamic, mechanically-robust hydrogel behaviors, with further extension to polymeric high internal phase emulsion (polyHIPE) materials for superabsorbency and high porosity. Fundamental studies will be performed to determine the properties of the intact materials, followed by investigation of their intentional depolymerization-based recyclability and long-term hydrolytic degradability. It is hypothesized that systematic investigation of networks that combine components of covalent linkages, supramolecular host-guest interactions, slide-ring topology and polyHIPE morphology will enhance the fundamental understanding of composition-structure-topology-morphology-properties relationships and lead to advanced materials that are capable of ultra-high water uptake kinetics and capacity, while exhibiting dynamic, responsive physicochemical and mechanical behaviors for broad applications. Importantly, techniques to build such materials from naturally-sourced feedstocks and with in-built depolymerization and disassembly routes will be developed to advance sustainability and recyclability.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.