A new approach for the reuse of scrap carbon fiber in high-added value continuous fiber reinforced composite structures

• This study proposed a novel processing method for reusing scrap carbon fibers. • Thermoplastic prepregs were produced via the wet-laid method. • These prepregs were then hot stacked with woven glass fabrics. • Carbon fiber in the laminates increased the flexural strength up to 60% • 140% improvement in the flexural strength was achieved after surface modification. This study proposes an innovative processing approach for high-added value hybrid fiber-reinforced composite structures by reusing scrap carbon fiber (CF). Thermoplastic prepregs were produced via wet-laid method using chopped polyamide 6.6 fibers as matrix and short scrap CFs as the reinforcing phase. These prepregs were then hot stacked with woven glass fabrics, forming a novel hybrid lightweight composite laminate. Silane treatment was used to improve the adhesion of glass fabric to the novel wet-laid scrap CF/PA6.6 prepregs. Tensile, flexural, dynamic-mechanical, and morphological properties of the composites were examined to characterize the effectiveness of the hybridization of short scrap CFs and glass fabric. The results showed that short scrap CF in the laminates increased the tensile strength up to 30% and flexural strength up to 60%. Moreover, silane surface modification of the glass fabric yielded a 140% improvement in the flexural strength of scrap CF/PA6.6 prepreg-glass fabric hybrid laminates.