Optimization of the formulation for the synthesis of bio-based foams
Résumé
Development of new eco-friendly materials destined to insulation applications is a major necessity. Aiming to contribute with this ecological strategy, we previously developed a new organic foam based on tannins and lignosulfonate. Our promising results lead us to analyze the role and impact of additives on the foaming process as well as on the solid foam properties. In fact, additives are critical factors in foam characterization since they define foam's properties. Thus, in the present study, we tested different additive concentrations, such as hexamine, glyoxal and tween 80, in order to have a better understanding of their impact on foam properties characteristics and performances aiming to improve foam fabricating process. The densities of the obtained foams varied from 105 to 188 kg/m3 and our study reveals that the mixture viscosity during foaming seems to play a crucial role in foam properties. Solvent, by diluting the mixture, tend to decrease mixture viscosity resulting in lower mechanical properties and density of the final material. Conversely, hexamine which act as bonding agent tend to increase mixture viscosity leading to higher density and mechanical resistance. Finally, some process enhancement propositions are discussing. © 2016 Elsevier Ltd