CLIMA/Collaborative Research: Discovery of Covalent Adaptable Networks for Sustainable Manufacturing and Recycling of Wind Turbine Blades

风能在可再生能源领域的持续增长是减缓气候变化的关键。然而，这需要建设大规模的能源基础设施，在制造和退役期间可能是能源和成本密集型的。特别是，在风力涡轮机叶片的制造和回收方面存在着关键的可持续性挑战。这些挑战源于风力涡轮机叶片结构基础的纤维增强热固性聚合物复合材料的永久性。这项气候变化减缓和适应民用基础设施研究（CLIMA）奖支持加速发现新聚合物家族的基础研究，共价适应性网络（can）及其复合材料具有机械强度且可逆，可回收，修复和再加工。从该项目中获得的知识将促进风力涡轮机叶片的成本效益制造和回收，从而提高风能在全球清洁能源领域的竞争力和可持续性，并扩大美国的工业和经济。此外，该项目还支持外展活动，以吸引国家实验室和风能行业的研究人员，对K-12学生进行复合材料、有机材料、计算机辅助设计和清洁能源方面的教育，招募本科生研究人员，特别是代表性不足的群体，并通过客座讲座丰富课程。共价适应性网络（can）是由共价键交联的聚合物，在加热或其他外部刺激下可逆。它们结合了热固性塑料的结构稳定性和热塑性塑料的延展性。本项目旨在建立一个系统的研究框架，以发现新的can及其复合材料，以满足风力涡轮机叶片的制造、运行和回收对材料性能的多方面要求。该研究以力学、材料和制造的跨学科合作为特色，包括三个组成部分：分子设计、有机材料合成和新聚合物的力学。对于分子设计，创建了一个结合机器学习和分子动力学（MD）模拟的网络平台来生成候选的can单体。合成组件建立了一个可行的分子设计空间，并允许从候选单体合成CAN聚合物用于制造和测试。力学部分侧重于测试和模拟CAN聚合物的力学行为。通过制备券级CAN复合材料样品，并将其机械性能与目前用于风力涡轮机叶片的热固性复合材料进行基准测试，将这三个组件集成在一起。研究了CAN复合材料的真空袋成型、热成型、层压和化学溶解等制造和回收工艺以及工艺条件的影响。该项目由工程理事会土木、机械和制造创新（CMMI）司的材料和结构力学（mom）和先进制造（AM）计划共同支持。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The continued growth of wind energy in the renewable energy landscape is key to the mitigation of climate change. However, this requires the construction of large-scale energy infrastructure that can be energy- and cost-intensive during manufacturing and decommissioning. In particular, there are critical sustainability challenges in the manufacturing and recycling of wind turbine blades. These challenges originate from the permanent nature of the fiber-reinforced thermoset polymer composites that underlie the structure of wind turbine blades. This CiviL Infrastructure research for climate change Mitigation and Adaptation (CLIMA) award supports fundamental research that accelerates the discovery of a new family of polymers, Covalent Adaptable Networks (CANs), and their composites that are mechanically strong yet reversible to enable recycling, repairing, and reprocessing. Knowledge to be obtained from this project facilitates cost-effective manufacturing and recycling of wind turbine blades, thereby improving the competitiveness and sustainability of wind energy in the global clean energy landscape and augmenting U.S. industry and economy. Additionally, this project supports outreach activities to engage researchers in national laboratories and the wind energy industry, educate K-12 students in composites, organic materials, computer-aided design and clean energy, recruit undergraduate researchers especially underrepresented groups, and enrich curricula through guest lectures.Covalent Adaptable Networks (CANs) are polymers crosslinked by covalent bonds that become reversible upon heating or other external stimuli. They combine the structural stability of thermosets and the malleability of thermoplastics. This project aims to establish a systematic research framework to discover new CANs and their composites to meet the multi-faceted requirements of material properties posed by the manufacturing, operation, and recycling of wind turbine blades. The research features an interdisciplinary collaboration among mechanics, materials, and manufacturing, and includes three components: molecular design, organic material synthesis, and mechanics of the new polymers. For molecular design, a cyber-platform combining machine learning and molecular dynamics (MD) simulations is created to generate candidate monomers of CANs. The synthesis component establishes a feasible molecular design space and allows CAN polymers to be synthesized from candidate monomers for manufacturing and testing. The mechanics component focuses on testing and modeling the mechanical behavior of the CAN polymers. The three components are integrated by preparing coupon-scale CAN composite samples and benchmarking their mechanical properties against the thermoset composites currently used in wind turbine blades. Manufacturing and recycling processes such as vacuum bag molding, thermoforming, lamination and chemical dissolution of CAN composites and the effects of processing conditions are also investigated. This project is supported jointly by the Mechanics of Materials and Structures (MoMS) and the Advanced Manufacturing (AM) programs of the Civil, Mechanical and Manufacturing Innovation (CMMI) Division in the Directorate for Engineering.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.