Composition containing isocyanate and isocyanurate groups, and rigid pur/pir foams produced therefrom
AssigneeCovestro Deutschland AG
InventorsChristos Karafilidis, Nicole Welsch, Marc Schumacher, Sabine Dippe, Rene Abels
Life of this patent
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Abstract
This disclosure provides compositions containing isocyanate and isocyanurate groups by allowing a pMDI to react in the presence of a trimerization catalyst, and the process for producing a rigid PUR/PIR foam from this composition. The disclosure further relates to the process for producing the compositions containing isocyanate and isocyanurate groups, to the production of rigid PUR/PIR foams from these compositions, to the rigid foams themselves, and to the use of such rigid foams.
Claims16
A process for producing an isocyanate- and isocyanurate-containing composition A2 comprising the steps of:
- 1. reacting a polyisocyanate A1 in the presence of a trimerization catalyst, and
- 2. stopping the reaction from step 1) using a suitable stopper to obtain the composition A2;
- wherein the trimerization catalyst is not an iminourea, a derivative of an iminourea or a free-radical initiator and the concentration of the employed trimerization catalyst is <0.50% by weight based on A1, and
- wherein the polyisocyanate A1 employed in step 1) is polymeric MDI having a content of monomeric diphenylmethane diisocyanate of <55% by weight and a viscosity of 130 to 400 mPa*s, at 25° C. as determined according to DIN 53019-1:2008-09 without solvent, and
- wherein step 2) is performed when the reaction mixture from step 1) comprises 5-<13% by weight of isocyanurate groups and has a viscosity of <2000 mPa*s at 25° C. as determined according to DIN 53019-1:2008-09 without solvent.
Dependencies are inferred from the claim text.