Polyhydroxyurethanes — sustainable materials with broad potential applications

The increased awareness against the toxicity of isocyanates have led researchers to develop synthesis pathways of polyurethanes without isocyanates. One promising class of non-isocyanate polyurethanes is known as polyhydroxyurethanes, which are prepared from reacting cyclic bicarbonates with diamines to form linear polyurethane chains with pendent hydroxyl groups. The sustainability features of polyhydroxyurethanes are discussed in the light of green chemistry principles, and their distinct kinds prepared from various renewable raw materials are presented. The potential applications of these partially/fully bio-sourced polyhydroxyurethanes are also reviewed while addressing their limitations and means to overcome them, so polyhydroxyurethane products can be eventually commercialized.