Improving interfacial adhesion and mechanical properties of carbon fiber reinforced polyamide 6 composites with environment-friendly water-based sizing agent. (1st June 2023)

• Record Type: Journal Article
• Authors: Yan, Chun; Zhu, Yingdan; Liu, Dong; Xu, Haibing; Chen, Gang; Chen, Mingda; Cai, Guangbin
• Is Part Of: Composites. Number 258(2023)
• Publication Date: 2023-06-01
• Subjects: Carbon fibers -- Interfacial adhesion -- Polyamide 6 -- Water-based sizing agent -- Mechanical properties; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2023.110675
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: In this study, a water-based aminoethylpiperazine-polyamide (AEPPA) is synthesized and its water-based sizing agent is prepared to improve the interfacial properties of carbon fiber reinforced polyamide 6 (CF/PA6) composites. The results show that the AEPPA sizing layer enhances the wettability of CF surface, thereby promoting the sufficient impregnation of PA6 resin on the fiber surface. Meanwhile, a strong interface is formed due to the interdiffusion and hydrogen bond formation between AEPPA and PA6 molecular chains. Accordingly, the interfacial shear strength increases by 29.3% and 20.2% from 41.9 MPa for as-received and 45.1 MPa for desized CF/PA6 composites to 54.2 MPa for 4 wt% AEPPA sizing agent treated CF/PA6 composites. In addition, to clarify the applicability of the resultant sizing agent, unidirectional CF/PA6 prepregs are prepared, and the mechanical properties of CF/PA6 composites are evaluated in detail. The average interlaminar shear strength, tensile strength and flexural strength increase by 14.2%, 10.5% and 20.0% from 73.8, 2198.1 and 1393.6 MPa for desized CF/PA6 composites to 84.3, 2638.7 and 1539.9 MPa for those treated with AEPPA sizing agent due to the effective stress transfer across the interface, respectively. Moreover, the cross-section morphologies and fracture behavior are analyzed to verify the improvement of mechanical properties. Furthermore, the strengthening mechanism of interfacial properties is intensively discussed.