Thermally Recyclable Soybean Oil-based Polyurethane Foams

Abstract: Soybean oil-based polyol (SO-polyol), the pioneer among biobased polyols in commercial market, has steadily gained traction in the polyurethane foam (PUF) industry. However, akin to petrochemical polyurethane and other thermoset foams and plastics, current soybean oil-based polyurethane foams (SO-PUFs) face limitations as they are neither recyclable nor compostable. To enhance the circularity of renewable PUFs and fully realize their sustainability potential, there is s a pressing need for advancements in their recyclability. 

In this study, we leverage dynamic covalent chemistry to introduce recyclability to current SO-PUF materials through straightforward modifications in both formulation and strcutural design.  Our primary focus is on accelerating reprocessability by manipulating the free hydroxyl content within the network structure and incorporating a cleavable chain extender/crosslinker during the preparation of SO-PUF. This approach not only significantly enhances the recycling rate through compression molding but also facilities rapid recycling through blending with waste thermoplastics.