A novel amine- functionalized apple peel biocarbon and beta vulgaris cellulosic fiber-based rigid vinyl-based microwave shielding composite

This present study investigates an eco-friendly electromagnetic interference (EMI) shielding material developed using cellulosic fiber and apple peel extracted biocarbon for safe electronic applications. The primary aim is to study how the biomass derived biocarbon influences in the wave shielding phenomenon. The fiber and filler both used from waste biomass which promotes circular economy and amine functionalization on both fiber and filler brings the novelty to this research. Further, the prepared composite under hand layup process is further assessed as per ASTM standards. Results revealed that due to the addition of surface modified cellulosic fiber and even dispersion of biochar particle into composite enhance mechanical, dielectric, EMI shielding effectiveness of the composite material. Thus, when compared to the plain vinyl ester resin (V), the amine functionalized cellulosic fiber reinforced composite material (V0) shows improved tensile, flexural and impact strength of 125 MPa, 151 MPa, and 4.1 J respectively. Further, the addition of biochar particle of 3 vol.% into the composite (V2) shows improved hydrophobicity behavior of 107° contact angle and the composite V2 further enhanced the tensile, flexural, impact strength of the composite of 145 MPa, 189 MPa, 5.1 J respectively. Moreover, the increase in biochar of 5 vol.% in to the composite (V3) shows effective dielectric loss of 0.28 in E band and 0.45 in J band. Furthermore, the composite under (V2) of 40 vol.% fiber, and 3 vol.% biochar shows maximum EMI shielding effectiveness of 8 dB in E band and 40 dB in J band, when compared to the 40 vol.% of fiber reinforced composite (V0) of EMI shielding effectiveness 9 dB in E band and 55 dB in J band respectively. Thus, this effective EMI shielding effectiveness, dielectric strength and load carrying capacity, impact strength and cost effective, light weight nature makes the composite material to be utilized in high signal protection applications, sensor, navigational devices, and various electric and electronic gadgets, etc.