In a study published in the Journal of Polymer Research, S. Gokulraj, K.G. Saravanan, K. Vijayakumar, and K. Arunkumar explored the effects of adding almond shell biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More to glass fiber-reinforced epoxy composites. The researchers investigated how incorporating this waste biomass-derived biochar influenced the composites’ mechanical and thermomechanical performance.  

The composites were made using a hand lay-up method, maintaining a constant 20% weight fraction of glass fiber and varying the almond shell biochar content from 0 to 20% by weight. The biochar, derived from almond shells, was uniformly dispersed in the epoxy resin using ultrasonication to ensure even distribution.  

The study’s key findings highlight that the addition of biochar affects the composite material’s properties. While higher biochar content increased water absorption, the mechanical properties showed an interesting trend. Specifically, the composite with 10% almond biochar exhibited the highest tensile strength (324.66 MPa) and flexural strength (376.12 MPa). This 10% composite showed an increase of 21.36 MPa in tensile strength and a 13.17% increase in flexural strength compared to the composite without biochar.  

Scanning electron microscopy (SEM) was used to examine the dispersion of particles within the composites and to analyze the tensile failure mode. Dynamic properties analysis revealed improved damping characteristics with the addition of 10% biochar, leading to higher storage modulus (8496.4 MPa) and loss modulus, indicating increased stiffness.  

Overall, this research demonstrates the potential of using almond shell biochar, an agricultural waste product, as a cost-effective reinforcement in polymer composites. The study highlights the efficacy of biochar in enhancing the material properties of these composites, contributing to more sustainable materials engineering.  

SOURCE: Gokulraj, S., Saravanan, K. G., Vijayakumar, K., & Arunkumar, K. (2025). Thermo-mechanical and mechanical performance of interlaced glass fiber epoxy hybrid composites reinforced with almond biochar biofiller. Journal of Polymer Research, 32(162)