Valorization of wood pulp to mechanically strong and biodegradable packaging foams by wet foaming process

This research focuses on developing environmentally friendly, biodegradable foams as alternatives to traditional petroleum-based materials like polyurethane and expanded polystyrene (EPS). Utilizing pulp and lignin through a cost-effective method, the study optimized factors such as sodium dodecyl sulfate (SDS) concentration, lignin content, and foaming time to achieve desirable mechanical properties and porosity. The box-behnken design identified optimal samples with varied characteristics, including densities from 0.013 g/cm³ to 0.077 g/cm³ and porosities from 95.2% to 99.2%. The introduction of lignin improved foam strength, with compression pressures ranging from 37.5 to 379 kPa. Additionally, the impact of chitosan on porosity, strength, and water resistance was examined. Incorporating 20 wt.% of chitosan enhanced strength by 4% and reduced water absorption by 60%. Over three months, the biodegradable foams displayed significant degradation, introducing them as sustainable alternatives to EPS for diverse applications like packaging.,