A Bio-based healable/renewable polyurethane elastomer derived from L-Tyrosine/Vanillin/Dimer acid

Bio-based, healable, and recyclable polyurethane materials conform to the sustainability of the polyurethane industry. By introducing dynamic covalent bonds, the cross-linked polyurethane can obtain the performance of network rearrangement, thereby realizing self-healing and reprocessing. In this work, a self-healing/renewable polyurethane based on bio-based vanillin and tyrosine was successfully synthesized solvent-freely and catalysts-freely. Due to two different thermal reversible mechanisms, metathesis of imines and deblocking/re-blocking of phenolic urethanes, the obtained PU has considerable selfhealing efficiency and renewability. At 120 degrees C, the surface scratches almost completely disappear within 90 min, and the tensile strength can be restored to similar to 95% within 2 h. After remolded for 5 times, the chemical structure, glass transition temperature, deblocking behavior, tensile strength, elongation at break and gel content didn't change significantly. Both the environmental friendliness of bio-based raw materials and the renewability of the obtained polyurethane materials meet the requirements of sustainability. (C) 2022 Published by Elsevier Ltd.