Upcycling of Carbon Fiber Reinforced Polymer for Thermal Management Application

Abstract

The utilization of carbon fiber reinforced epoxy resin (CFRE) has gained remarkable prominence across diverse industrial domains due to its excellent rigidity, hardness, and corrosion resistance. However, the intricate three-dimensional network crosslinked structure of thermosetting epoxy resin engenders formidable challenge in the realm of material recycling for further value-added products. In this paper, solid-state shear milling (S3M) technology is applied to removal of the epoxy resin matrix enshrouching the carbon fiber surface, facilitating the subsequent fabrication of value-added PA/WFRE/BN composite through the incorporation of boron nitride (BN). The BN engenders a progressive connection with the high aspect ratio carbon fiber and established cohesive thermal conductivity network. Specifically, the thermal conductivity of PA/ WFRE/BN-20 reached 1.24 W/mK escalated by an impressive 375% vs pristine polyamide (PA), and resistivity is higher than 10 10 Ω•cm. An excellent thermal management performance can also be noticed for PA/WFRE/BN-20 composite, whose surface temperature drops from 60 to 20 °C in only 55 s, which is much shorter than PA/BN-20 (almost 100 s). Furthermore, the tensile and flexural strengths of the composite reached as high as 88.6 and 127.7 MPa, which are 76% and 93% higher than pristine PA. In summation, this work offered a facile pathway for the fabrication of value-added thermal management composites from waste carbon fiber reinforced epoxy and showed a promising strategy for the upgrade recycling of thermosetting resins.