A critical study on interfacial modification and scalable processing of high-performance regenerated carbon fiber reinforced thermoplastic composites from waste CFRP
Ming‐Yuan Shen, Zih‐Hao Guo, Weilin Liu
Abstract
The substantial annual generation of carbon fiber–reinforced polymer (CFRP) waste from key industries, including sporting goods and aerospace, poses a serious environmental challenge, as most of this material is disposed of via landfilling. This study demonstrates a scalable and industrially viable process to fabricate high-performance carbon–reinforced thermoplastic composites (CFRTP) from regenerated carbon fibers (rCF) to address this issue. The rCF were recovered from discarded bicycle frames and wind turbine blade spars via microwave-assisted pyrolysis, subsequently surface-modified with a novel modifier, and compounded with polyamide 66 (PA66) using a custom-designed high-temperature dispersion kneader. Experimental results revealed that an optimal 5 wt.% surface modification yielded comprehensive mechanical enhancements over unmodified composites, including increases in tensile strength (+ 10.0%), Young’s modulus (+ 22.8%), flexural strength (+ 8.3%), flexural modulus (+ 13.1%), and impact strength (+ 23.8%). Notably, the modified rCF composites also outperformed a benchmark commercial composite (reinforced with virgin carbon fibers) in tensile strength (by 20.3%) and flexural strength (by 21.4%). Scanning electron microscopy analysis attributed this superiority to enhanced fiber-matrix bonding and greater fiber length retention, a direct result of the low-shear nature and high-dispersion efficiency of the kneader process. This work validates a robust pathway for the high-value recycling of CFRP waste, offering a sustainable solution for producing high-performance composites with strong potential for industrial applications in the automotive and sporting goods sectors.