Development and thermal performance of aerogel-based cellulose composites for thermal insulation applications

Cellulose, a sustainable and eco-friendly material comprising around 85% recycled waste paper, could be utilized as a thermal insulation material. However, its low moisture resistance limits its feasibility under extremely harsh weather. Furthermore, it also requires a high thickness to achieve certain thermal resistance, which reduces the interior space in small buildings. To improve the performance of cellulose, this study aims to develop a thermally efficient, sustainable, and low-cost composite material utilizing cellulose and aerogel particles along with selective additives such as surfactant, binder, and rheology modifier. A detailed experimental study using the modified transient plane source (MTPS) method was conducted by systematically assessing the effect of each component on the thermal conductivity of the composite, based on 265 test specimens. The study was initiated by studying the thermal conduction of homogenous cellulose, followed by the addition of aerogel particles, surfactant, binder, and finally rheology modifier at varying concentrations. The effect of density and moisture content on the thermal conductivity of the composite was also investigated. It was observed that increasing aerogel from 0% to 50% by volume resulted in a thermal conductivity of 0.0551 and 0.0321 W/m.K, representing around a 42% reduction. Using 4.5% surfactant volume, the conductivity was further reduced to 0.0307 W/m.K, whereas adding up to 4% binder and 2.5% rheology modifier has a minimal effect on thermal conduction. Utilizing the super-insulating properties of aerogel and the low-cost and sustainability of cellulose, the proposed composite insulation material could be a robust option for housing in extreme environments. • The study developed an aerogel-based cellulose composite for thermal insulation • Aerogel addition (0-50%) reduced thermal conductivity by 42% • Thermal mapping enhanced aerogel dispersion with surfactant • A small amount of Binder and rheology modifier showed minimal effect on λ • The developed composite was found to be suitable for buildings in extreme climates