A multifunctional epoxy composites based on cellulose nanofiber/carbon nanotube aerogels: Simultaneously enhancing fire-safety, thermal conductive and photothermal performance

As 5G technology develops and electronic power density increases, preparing epoxy resin (EP) composites with excellent fire-safety, thermostability, and thermal conductivity remains challenging. Herein, hexaphenoxy cyclotriphosphazene and poly(piperazine methylphosphonic acid pentaerythritol ester) were used as synergistic flame retardants (FR) for EP. The cellulose nanofiber/carboxylated multiwalled carbon nanotubes aerogels (CCA 80 ) were prepared and immersed into the EP and FR mixture to obtain EP/CCA 80 /FR composites. Compared with neat EP, the limiting oxygen index of EP/CCA 80 /6 wt% FR increased by 38.9 %, the total heat release and CO 2 production rate decreased by 30.61 % and 39.47 %, respectively, achieving the UL-94 V-0 rating. Moreover, its thermal conductivity was 1.06 W · m −1 ·K −1 , 457.9 % higher than neat EP, while maintaining excellent electrical insulation. Its surface temperature maintained at 94.5 °C under 1.0 kW·m −2 irradiation for 2 h, exhibiting good photothermal conversion capability and photobleaching resistance. A novel fabrication methodology of multifunctional EP composites for high-performance electronic component was proposed.