MDI is a hot potatoes. High performance versus health with isocyanate monomers

Polyurethanes are products of the reaction of polyols and polyisocyanates. Polyols are easy to replace by renewable resources as hydroxyl groups are common in natural products whereas isocyanates are usually based on petrochemical resources. Aromatic socyanates are suspected of being cancerogenic whereas some aliphatic isocyanates are toxic. Probably the aim is not changing to non-isocyanate routes but to monomer free hardeners. Polyurethanes based on 100 % renewable raw materials means to avoid isocyanates due to their production via the phosgene process. Waiving of isocyantes however seems to be hardly possible from the current point of knowledge. Polyurethanes are uniting outstanding chemical and excellent mechanical resistance as well as high elasticity in a unique way. Discussing the isocynate categorization in an industrial environment means to discuss formaldehyde containing x-linkers in the same moment, for formaldehyde is also declared carcinogenic cat.