Application of bio-based polyurethanes in construction: A state-of-the-art review

This paper presents a comparative analysis of bio-based polyurethane insulations and conventional polyurethanes, emphasizing their mechanical properties, thermal and acoustic performance, environmental benefits, and fire resistance. It addresses health and indoor air quality concerns related to volatile organic compounds and formaldehyde emissions from conventional polyurethanes, advocating for a transition to bio-based alternatives in construction to mitigate negative health and environmental impacts. The findings indicate that the eco-friendliness of bio-based polyurethane insulation hinges on the careful selection of bio-components to ensure sustainability compared to their petroleum-based counterparts. However, challenges persist in this area, particularly in optimizing the extraction and purification methods for bio-based polyols. Additionally, while the inclusion of bio-based components such as bio-oils and fillers enhances the properties of the insulation—improving sound absorption and thermal performance due to their porous structure—there is still limited research on the emissions associated with these materials. The review highlights significant research gaps, particularly regarding the environmental impact and performance of bio-based polyurethanes, and calls for comprehensive life-cycle assessments and cost analyses to substantiate their environmental and economic benefits. Future research directions should also include evaluating the recyclability of bio-based foams versus conventional foams, as well as addressing the challenges of integrating bio-based materials into building codes and standards, which can impede widespread adoption. By overcoming these obstacles, the sustainability and performance of bio-based polyurethane insulation products can be significantly improved.