Improving Mechanical and Thermal Properties of Cellulose Foam with Alumina Nanofibers

Foam-formed cellulose biocomposites provide a promising, innovative approach to creating lightweight and eco-friendly materials for utilization in packaging and insulation. This study investigates the production and characterization of temperature-resistant, mechanically stable cellulose fiber (CF) composite foams reinforced with alumina nanofibers (ANFs). To evaluate the impact of ANFs on rheology and drainage, CF suspensions were prepared at a concentration of 20 g/kg, with ANFs added at 2 wt% and 5 wt%. All foams exhibited shear-thinning behavior, with variations in flow characteristics influenced by ANF consistency and particle-bubble interactions. ANFs were integrated into the dry CF foam structure using two methods: (i) immersion in an ANF water suspension, and (ii) direct injection of the suspension into the foam matrix. Mechanical and thermal analyses of the dried CF foams with 2% ANFs demonstrated significant improvements in strength and thermal stability. Incorporating ANFs into CF-based foams enhances their rheological properties, improves mechanical and thermal performance, and reduces combustion rates. These results highlight the potential of ANF-reinforced CF foams for use in industries requiring biodegradable insulation and packaging materials.