Mechanical, thermal conductivity, and water absorption properties of biosilica and palm kernel fiber reinforced epoxy composite rebar for building materials

• Published in: Biomass conversion and biorefinery 2024, Vol.14 (16), p.19973-19983
• Main Authors: Sasirekha, S., Giridharan, K., Chakravarthi, G.
• Format: Article
• Language: English
• Subjects: Biotechnology; Bonding strength; Building materials; Chemical synthesis; Compressive strength; Energy; Epoxy resins; Fiber composites; Fiber reinforced polymers; Fiber-matrix adhesion; Fillers; Flexural strength; Heat conductivity; Heat transfer; Interfacial bonding; Microstructural analysis; Millet; Original Article; Pressure molding; Rebar; Renewable and Green Energy; Stress transfer; Tensile strength; Thermal conductivity; Thermodynamic properties; Variance analysis; Water absorption; Water hardness
• ISSN: 2190-6815; 2190-6823
• DOI: 10.1007/s13399-024-05838-1

This research explores the mechanical, thermal conductivity, and water absorption characteristics of epoxy-based composite rebar material reinforced with biosilica derived from proso millet husks and palm kernel fiber. The main objective of this research study is to investigate the effect of biosilica addition into the natural fiber reinforced epoxy resin rebar and its load bearing characteristics. The biosilica is synthesized from waste proso millet husks via thermo-chemical method and the composites were made using mold in the name of PP, PP1, PP2, PP3, and PP4. Series of tests including tensile, flexural, compression, hardness, water absorption, and thermal conductivity were performed on the composite rebar and analyzed rigorously. Results indicate that PP3 exhibits superior tensile strength (114 MPa), flexural strength (156 MPa), and compression strength (132 MPa) compared to other samples. This improvement is attributed to the optimized dispersion of biosilica filler within the resin matrix, leading to enhanced interfacial bonding and stress transfer mechanisms. Conversely, PP4 displays enhanced hardness of Shore-D 82, increased water absorption of 0.044%, and reduced thermal conductivity of 0.196 W/mK. Microstructural analysis using SEM reveals enhanced fiber-matrix adhesion and reinforcement in PP3 and PP4. According to ANOVA, the results are significant with P value of 3.386e −14 . Overall, these findings suggest that incorporating biosilica filler enhanced the mechanical and thermal properties of the composites, with PP3 and PP4 demonstrating promising attributes for a variety of engineering applications such as structural, pre-casted walls, hand rails, and readymade wall portions.