Recycling Polyurethanes through Transcarbamoylation.

In this paper, we describe a new strategy to recycle polyurethanes (PUs) using base-catalyzed transcarbamoylation. PUs were depolymerized qualitatively in the presence of MeOH (methanol)/tetrahydrofuran as a solvent and -butoxide as a base catalyst. The resulting depolymerized mixture constituted by -dimethylcarbamates and polyols can either be used as the starting material to synthesize new PUs with the transcarbamoylation approach or be purified to recover polyols and diisocyanates. The versatility and easy scaling-up of the experimental procedures and high depolymerization outcomes of the presented method make this strategy very attractive for PU recycling.