Design and Development of a Bio-Based Hybrid Polyurethane Foam for Sustainable Thermal Insulation Applications

In the context of global efforts to reduce energy consumption in buildings, polyurethane insulation panels play a crucial role. The work focuses on replacing petroleum-derived components in conventional polyurethanes with bio-based alternatives sourced from lignocellulosic biomass. The developed material consists of a hybrid polyurethane foam in which conventional polyols are replaced with lignin-derived ones. A key innovative step is the incorporation of cellulose nanocrystals into the polyurethane matrix which acts as a multifunctional additive. Thermal constant characterization was conducted, accompanied by Scanning Electron Microscopy imaging analyses of cellulose nanocrystals. This methodological approach enabled a rigorous evaluation of the technical implications of lignin and cellulose nanocrystals utilization, providing a solid framework for interpreting differences in material behavior and assessing the feasibility of lignin as a functional component in advanced polyurethanes.