Isocyanate-Free Polyurethane Coatings through Thermal Diazirine Curing

de Zwart, F.J.; Wolzak, L.A.; van den Berg, K.J.; Baran, M.J.; Wulff, J.E.; Flapper, J.; de Bruin, B.

ACS Appl. Polym. Mater. 2024, 6, 6, 3517–3522

https://www.doi.org/10.1021/acsapm.4c00266  

Polyurethane coatings have strong material properties due to the hydrogen bonding inherent to the urethane groups. However, installing this urethane moiety usually requires curing through difficult-to-handle isocyanates. In this work, we show the development of a polyurethane-based crosslinker that can be used to formulate a one-component polyurethane coating with material properties similar to those of isocyanate-based polyurethane coatings. To achieve this, we used diazirine functionalities that generate carbenes upon heating, which react with alcohol functionalities in a polyol to generate a crosslinked network with a high storage modulus.