Optimized synthesis of a high oleic sunflower oil derived polyamine and its lignin-based NIPUs

In the continuing effort towards reducing reliance on fossil resources, the transition to biobased materials is of utmost importance, together with the adoption of more sustainable and safe production processes. This work focuses on the implementation of renewable resources and greener protocols for the synthesis of a bio-based amino crosslinker and its subsequent use in non-isocyanate polyurethane (NIPU) synthesis. NIPUs are a new class of materials, analogous to isocyanate derived polyurethanes (PUs), that avoid hazardous chemicals in their production process, such as phosgene and isocyanates, that raise high concern in the PU manufacturing processes. Vegetable oils and lignin are two abundant renewable feedstocks largely investigated during the last decade. In this paper, we study the synthesis of a high oleic sunflower oil derived polyamine (PA) via thiol–ene photoreaction in batch and in flow. Additionally, cyclic carbonate functionalized lignin (CCLF) was synthesized and reacted with PA to create fully bio-based NIPU networks with different lignin contents. The curing behavior as well as the characterization of the obtained thermosets is described.