Effect of carbon fiber content on thermal and electrical conductivity, EMI shielding efficiency, and radiation energy of CMC/PVA composite papers with carbon fibers

Abstract

In this study, the thermal, electrical, and mechanical properties, as well as the electromagnetic interference shielding efficiency (EMI-SE), of carboxymethylcellulose (CMC)/polyvinyl alcohol (PVA)/carbon fiber (CF) composite paper (CP), fabricated by a wet-laid process, were examined based on the CF content. The emissivity and radiation energy of the CP were also measured. Uniformly dispersed fibers in the CF3 sample with a basis weight of 50.32 g/m2 and dimensions of 50 mm × 50 mm exhibited good properties: high tensile strength of 11.5 MPa, low power density of 3133 W/m2, low surface resistance of 2.27 ohm/sq, high surface heat temperature of 111.6 °C at 5 V, high EMI-SE of 61.63 dB (1.5 GHz), and good emissivity and radiation energy of 0.915 and 3.53 × 102 W/m2, respectively, at 37 °C. The most efficient CF3 for electrical heaters with uniform temperature distribution was obtained at the optimal concentrations of 92 wt% CMC, 5 wt% CF, and 3 wt% PVA in the system.