Besides rigid polyurethane foam (PUR) Nestaan also produces rigid polyisocyanurate foam (PIR). PUR as a material has some advantages on PIR; it is more flexible and cheaper to produce. Why should we make PIR? For a very important reason: the excellent fire behaviour.
PIR foam is made by mixing a polyol blend with an isocyanate. Adding a blowing agent to this mixture enables the foaming process. The different chains in the molecular web that originate after the reaction give the foam its specific features. When the PUR-joint is more flexible and less brittle, PIR foams exhibit increased fire performance and reduced combustibility and higher service temperature limits compared to PUR. During a fire PIR foam creates a carbon skin that prevents a fast expansion of the fire.
PIR is produced in the same dimensions as PUR, with thicknesses from 10 to 680 mm. All PIR products are B2 according to DIN 4102 and M3 according to Epiradiateur. A special quality M1 for the French and UK market is also available.