Improved wear resistance and recycling of carbon fiber/epoxy composites via incorporation of regenerated lignin cellulose

Combining wood matrix with thermosetting resin promises to be a new generation of resin-based friction material alternatives. Herein, regenerated lignin-cellulose (RLC) was prepared by waste wood, and precursor matrix slurry (EP@RLC) was obtained by mixing aqueous epoxy resin (EP) with RLC in different proportions. The impregnation and low-temperature curing processes were used to realize the combination of carbon fibers (CFs) and wood-plastic matrix. RLC filled the voids between CFs and adhered to their surfaces to build a CF-RLC reinforced structure, improving the surface roughness of the CFs/wood-plastic resin-based composite (CFs/EP@RLC) and enhancing the tensile strength and wear resistance. It has excellent mechanical strength with the tensile strength of up to 151.9 MPa, tensile modulus of up to 8.52 GPa, and toughness of up to 9.05 MJ/m3. In the tribological performance test, CFs/EP@RLC showed a stable friction coefficient (0.06) and low wear rate (0.64 mm), and no damage occurred at the interface of CFs after a long period of cyclic testing. In comparison with current research on resin-based friction materials, the CFs/EP@RLC meet the requirements in terms of mechanical and tribological properties. Besides, the CFs contained in end-of-life products can be easily recovered in hot alkaline solutions.