Binary hybrid filler composite formulations of surface modified Fe–Si–Al alloys for multifunctional EMI shielding and thermal conduction

Sendust/expanded graphite and Sendust/boron nitride binary composite fillers adhered through surface silane modification and their non-modified, simply mixed, polymer composites were fabricated for optimization of multifunctional EMI shielding and thermal conduction properties. The effect of filler type, filler content, surface modification, and dispersion properties in thermoplastic polyurethane matrix were examined. Through extensive screening of hybrid composite compositions, tunable properties in EMI shielding (2.8–32.1 dB at 3 GHz and 7.6–48 dB at 10 GHz, sample thickness 0.6 mm), through-plane thermal conductivity (0.3–1.694 W/mK), and in-plane thermal conductivity 1.102–6.084 W/mK) were elucidated through electrical conductivity measurements and dispersion morphology within the polymer matrix. The composite materials database reported in this study allows for the selection of customizable properties according to desired application.