| abstract |
The present invention relates to a method for producing a composite element comprising a thermal insulation material (B), a binder (C) and optionally at least one outer layer (A) by bonding the thermal insulation material (B) with the binder (C). ) adhesive; wherein the adhesive (C) is a polyurethane adhesive, which can be prepared by combining a polyisocyanate (a) with a polyol (b) having at least two isocyanate-reactive groups, an aqueous A foaming agent (c) is mixed with an optional chain extender (d), a catalyst (e) and other auxiliaries (f), wherein the polyol (b) comprises a polyether alcohol, and the polyether alcohol comprises 50 to 90% by weight of at least one polyalkylene oxide (b1), 10 to 50% by weight of at least one polyalkylene oxide (b2) and 0 to 30% by weight of at least one other polyalkylene oxide (b3) , each based on the total weight of components (b1) to (b3); the polyalkylene oxide (b1) has a hydroxyl value of 120 to 300 mg KOH/g, based on bifunctional initiator molecules, and ethylene oxide The alkane content is 60 to 100% by weight, based on the content of the alkylene oxide, and the proportion of primary OH groups is 50 to 100%; the polyalkylene oxide (b2) has a hydroxyl value of 120 to 600 mg KOH/g , based on the bifunctional and/or trifunctional initiator molecules, and the ethylene oxide content is 0 to 40% by weight, based on the alkylene oxide content; the polyalkylene oxide (b3) has a hydroxyl value of 100 to 800 mg KOH/g, based on bifunctional to tetrafunctional starter molecules. The present invention also relates to a composite element, which can be produced by the above-described method, consisting of a thermally insulating material (B) and an adhesive (C) and optionally at least one outer layer (A), and to the adhesive (C) for bonding It is suitable for the purpose of thermal insulation material (B). |