Interface strengthening for carbon fiber‐reinforced poly(ether‐ether‐ketone) laminated composites by introducing fluorene‐containing branched poly(aryl‐ether‐ketone)
Zheng Liu, Xuerong Fan, Xinghan Lu, Xuetao Shi, Junliang Zhang, Hua Guo, Mukun He, Junwei Gu
Abstract
Abstract Fluorene‐containing branched poly(aryl‐ether‐ketone) (BFPAEK) with terminal hydroxyl groups is synthesized by random copolycondensation reaction; then, the CF@BFPAEK/PEEK laminated composite is prepared by the “powder impregnation‐high temperature compression molding” method with poly(ether‐ether‐ketone) (PEEK) as the matrix and BFPAEK‐modified carbon fiber (CF@BFPAEK) as the reinforcement. When the content of branched units in BFPAEK is 10% and the coating amount of BFPAEK on the carbon fiber (CF) surface is 3 wt%, the CF@BFPAEK/PEEK laminated composite has outstanding mechanical properties, with an interlaminar shear strength (ILSS) of 57.3 MPa and flexural strength of 589.4 MPa, which are 80.2% and 44.3% higher than those of the pure CF/PEEK laminated composite (31.8 and 408.4 MPa), respectively. After 288 h of hydrothermal aging and high/low‐temperature alternating aging, the corresponding retention rate of ILSS and flexural strength are respectively 87.9% and 84.7%, higher than those of pure CF/PEEK laminated composites (74.5% and 70.4%). The thermal conductivity coefficient and temperature for 5% weight loss of CF@BFPAEK/PEEK laminated composite are 1.85 W m −1 K −1 and 538.0°C, respectively.