Transforming agriculture waste into useful filler for a sustainable epoxy-glass fabric composites: microwave absorbing applications

The electronic industry is compelled to improve its environmental performance by making use of agriculture wastes and cleaner manufacturing process. This paper provides the use of silica rich rice husk ash (RHA) as reinforcement for the epoxy (EP)-glass fiber (GF) composites for the development of radar/microwave absorbing material (RAM). The EP/GF/RHA hybrid laminates with RHA content of 0, 5, 10 and 15 wt.% were fabricated by hand layup technique. Scanning electron microscope was used to see the dispersion of RHA particles in the hybrids. Addition of RHA improved the storage modulus (E′) remarkably both in the glassy as well as rubbery regimes. The hybrid containing 5 wt.% RHA showed stiffness higher by 21.5% than the EP/GF matrix without RHA. Amongst hybrids, 5 wt.% RHA containing hybrid exhibited good microwave absorption properties with maximum reflection loss (RL_max) of—8.12 dB at 11.29 GHz frequency.