Upcycling of Carbon Fiber/Thermoset Composites into High‐Performance Elastomers and Repurposed Carbon Fibers

Abstract

Recycling of carbon fiber‐reinforced polymer composites (CFRCs) based on thermosetting plastics is difficult. In the present study, high‐performance CFRCs are fabricated through complexation of aromatic pinacol‐cross‐linked polyurethane (PU‐AP) thermosets with carbon fiber (CF) cloths. PU‐AP thermosets exhibit a breaking strength of 95.5 MPa and toughness of 473.6 MJ m‐3 and contain abundant hydrogen‐bonding groups, which can have strong adhesion with CFs. Because of the high interfacial adhesion between CF cloths and PU‐AP thermosets and high toughness of PU‐AP thermosets, CF/PU‐AP composites possess a high tensile strength of >870 MPa. Upon heating in N,N‐dimethylacetamide (DMAc) at 100 °C, the aromatic pinacols in the CF/PU‐AP composites can be cleaved, generating non‐destructive CF cloths and linear polymers that can be converted to high‐performance elastomers. The elastomers are mechanically robust, healable, reprocessable, and damage‐resistant with an extremely high tensile strength of 74.2 MPa and fracture energy of 149.6 kJ m‐2. As a result, dissociation of CF/PU‐AP composites enables the recovery of reusable CF cloths and high‐performance elastomers, thus realizing the upcycling of CF/PU‐AP composites.

Ligand Dissociation of Metal-Complex Photocatalysts toward pH-Photomanipulation in Dynamic Covalent Hydrogels for Printing Reprocessable and Recyclable Devices

“…Dynamic polymers have garnered significant attention due to their unique dynamic features and similar mechanical performances to traditional static polymers. − Their reversible networks allow them to reconfigure and restructure, with potential applications in high-performance smart materials, soft devices, electronics, and other fields. − For example, programmatically controlling the dynamic equilibrium in polymers enables precise shape-memory behavior in specific environments. − Their dynamic nature gives them excellent self-healing, reprocessable, and recyclable properties under external stimuli. − Especially dynamic hydrogels, with their water-rich and porous structures, offer biomimetic microenvironments, while reversible bonding provides mechanical dynamics for stiffness control in cell culture, tissue repair, and conformable bioelectronics fabrication. − Moreover, dynamic polymer hydrogels with covalent bonding interactions demonstrate superior mechanical performance to those with noncovalent interactions. Combining hydrogel preparation with emerging additive manufacturing technologies can further extend their advanced applications with complex structures. , Therefore, developing high-performance dynamic covalent hydrogels is essential and presents an intriguing topic in related fields.…”