The primary goal of the research is to develop a resilient material for electromagnetic interference (EMI) shielding. This study investigates the mechanical, dielectric, and electromagnetic interference (EMI) shielding properties of a composite material reinforced with biocarbon extracted from abaca bract and pineapple fiber in a rigid vinyl ester matrix. The biocarbon is obtained through a pyrolysis process, ensuring its origin from sustainable sources. The fabrication process involves employing the hand layup method, adhering to ASTM standards for comprehensive characterization. Among the fabricated composites, VB3, featuring 2 vol% of biocarbon and 40 vol% of pineapple mat fiber, stands out for exhibiting superior mechanical properties. It achieves a tensile strength of 143 MPa, flexural strength of 184 MPa, compression strength of 161 MPa, and impact energy of 4.31 J. Conversely, VB4, with a higher volume of biocarbon, experiences a slight reduction in mechanical properties attributed to biocarbon agglomeration, while showcasing an enhanced Shore-D hardness of 82. Silane treatment of both pineapple fiber and biocarbon contributes to improved adhesion in the matrix. In terms of electromagnetic interference (EMI) shielding, VB4 surpasses others, delivering maximum shielding effectiveness with total shielding values of 11.18 dB, 30.53 dB, 54.16 dB, and 65.51 dB for frequency bands at 8 GHz, 12 GHz, 16 GHz, and 20 GHz. Similarly, in dielectric properties, VB4 outperforms other designations with a dielectric constant of 9.8, 7.4, 5.8, 4.5, and dielectric loss values of 0.15, 0.31, 0.42, and 0.5 for the respective frequency bands. Moreover, increased biocarbon content further enhances the hydrophobic behavior of the matrix in VB4, achieving a water contact angle of 97°.These findings highlight the multifunctional capabilities of VB4, demonstrating not only superior mechanical strength and EMI shielding but also enhanced dielectric properties and hydrophobic nature. The comprehensive approach to incorporating biocarbon and pineapple fiber, coupled with silane treatment, contributes to the overall performance and versatility of the composite material.
