Akademik Veri Yönetim Sistemi
Journal of Polymer Science, cilt.64, sa.4, ss.1041-1057, 2026 (SCI-Expanded, Scopus)
This study presents a novel, systematic approach to developing lightweight, flexible microwave absorbing composites based on styrene–butadiene–styrene (SBS) filled with conductive and magnetic fillers. Graphite and nickel powders were combined to simultaneously introduce dielectric and magnetic loss mechanisms, allowing their combined effect to enhance microwave absorption, while a physical blowing agent created microcellular foam at two target densities (0.6 and 0.44 g cm−3) to evaluate porosity effects. Systematic variation of filler ratios and foam morphology enabled tuning of dielectric–magnetic interactions and impedance matching. Scanning electron microscopy showed nickel addition affected graphite dispersion, and higher blowing agent content produced finer, more uniform cells; dielectric and magnetic characterization revealed enhanced permittivity and magnetic permeability from interfacial polarization and magnetic dipolar effects, especially in the optimal 40 phr graphite/40 phr nickel formulation. This composite showed a minimum reflection loss (RLmin) of −18 dB and an effective absorption bandwidth of 9.71–12.50 GHz (~2.79 GHz) (at ~0.6 mm), outperforming the graphite-only composite with 40 phr filler, which exhibited only a narrow window near 8–9 GHz (~1.0 GHz). Further enhancement was achieved with the foamed version at 0.44 g cm−3, where the finer, more homogeneous cellular morphology yielded RLmin = −54 dB (10.49 GHz) and broadband coverage across the X-band (8.0–12.5 GHz) at ~0.8 mm.