3. Reducing isocyanate toxicity

Isocyanates are essential components in the preparation of PUs. However, with current health and environmental concerns (notably changes in REACH regulations) linked to the synthesis or use of isocyanates, research groups and industries are working intensively to replace isocyanates with safer alternatives and to use precursors of biobased origin. In this section, alternatives to isocyanates and strategies to reduce their toxicity are presented.