Chitosan foams with promising mechanical properties, heat-insulating ability, and flame retardancy were produced through oven drying. The chitosan foams were reinforced with cellulose, boric acid, and different ratios of activated carbon. The foams showed desirable low density (80.2 to 109.8 kg/m3) and compression properties. The compression resistance and compression modulus of foams ranged between 53.6 and 98.5 KPa and 214 to 394 KPa, respectively. Thermal conductivity tests revealed that the foams endowed low thermal conductivity values (0.035 to 0.051 W/mK). The limiting oxygen index (LOI) of the foams was as high as 32.9% for activated carbon (20 g/L). The activated carbon reinforcement produced higher thermal properties and decreased the mass loss 48.1% at 600 °C. The produced foams exhibited good biodegradability (39% degradation in 15 days). The overall test results showed that the chitosan foams can be utilized as a promising environmentally friendly material in thermal insulation fields
