Fire-performance lightweight cellulose-based composite for thermal insulation

Abstract Bio-based construction materials show strong market potential and are expected to gain popularity. However, their widespread use in the construction industry requires overcoming key challenges, such as enhancing fire and biodeterioration performance while maintaining recyclability and safe disposal options. The aim of the research was to develop a lightweight cellulose-based composite for use as an insulation material, focusing on enhanced fire performance and temporary biological durability. The cellulose-based composites demonstrate promising fire performance, with SBI test results indicating the potential to achieve Euroclass B or C. They are biodegradable and susceptible to degradation by brown and white rot fungi. The addition of expanded graphite reduced mass loss by about 30%, while boron compounds, by increasing the material’s moisture content, effectively limited fungal growth due to their toxicity, thereby reducing biodeterioration. In terms of insulation properties, the composites feature low thermal conductivity and high heat capacity, making them promising insulating materials with good energy buffering capacity. However, composites containing boron compounds are less practical as thermal insulators due to their high hygroscopicity, which reduces insulation efficiency under moist conditions. The developed materials demonstrate high potential for application as specialized thermal insulation materials in the construction sector due to their biodegradable nature and enhanced fire performance.