Experimental Investigation of thermal conductivity of bio based composite material made from jute, cotton and coir fibers

This research investigates the production and thermal evaluation of a novel ternary hybrid composite consisting of Jute, Cotton, and Coir fibers arranged in a symmetric J-Ct-Co-Ct-J stacking sequence. As the global demand for eco-friendly construction materials rises, natural fiber hybrids offer a low-cost, biodegradable alternative to synthetic petroleum based insulators. In this study, two distinct samples with varying thicknesses (5.2 mm and 13.8 mm) were fabricated using the hand lay-up technique. The thermal conductivity (k) was experimentally determined using the Lee’s Disc method, applying Fourier’s Law of Heat Conduction under steady-state conditions. The results indicate a significant thickness-dependent insulation effect; Sample B (13 layers) achieved a thermal conductivity of 0.092 W/mK, representing a 37.8% reduction compared to the thinner 5-layer Sample A. This enhancement is attributed to the increased inter-facial thermal resistance and air entrainment within the porous coir-cotton core. The findings suggest that the proposed ternary hybrid architecture provides a superior thermal barrier, making it a viable candidate for green building insulation and sustainable packaging applications.