PUR - POLYURETHANE
Polyurethane is a huge family of polymers in which the polimeric chain is formed by urethane links -NH-(CO)-O-. Urethane polymers are widely used in the production of great variety of materials. Polyurethanes are obtained after a reaction between a di-isocianate (aromatic or aliphatic) and a polyol (tipically a polyethylen- or polyestherglicole) , furthermore catalysts are added to improve yield of reaction and other additives that give specific features to the maetrial; particularly "surfactants" to modify the surface aspect, flame retardants and/or blowing agents.