Process and composition for preparing reactive melts based on surface-deactivated solid isocyanates and polymers with functional groups

Production of a heat-curable composition (C1) that melts above room temperature comprises dispersing a surface-deactivated solid polyisocyanate (I) in a first monomer, oligomer or prepolymer (II) and adding a second monomer, oligomer or prepolymer (III) that reacts with (II) to form an oligomer or polymer (IV) having isocyanate-reactive groups. Independent claims are also included for: (1) production of a heat-curable composition (C2) in the form of particles smaller than 500 mu m by coating a substrate with C1 above its softening point before (IV) has completely formed and removing particles from the substrate after cooling and subsequent complete formation of (IV); (2) composition C2 in the form of uncomminuted particles; (3) production of a substrate coated with a heat-curable composition (C3) in the form of a film thinner than 500 mu m by coating the substrate with C1 above its softening point before (IV) has completely formed using a spray nozzle, doctor or roller; (4) composition C3 in the form of an nonrolled film; (5) substrate coated with C3; (6) kit comprising (I) and (II) in one compartment and (III) in another compartment; (7) glueing substrates by applying C1 to a first substrate to form a latently reactive film, optionally shaping the film at a temperature above the melting or softening point of (IV), heating the film to a temperature at which (I) reacts with (IV), and contacting a second substrate with the film. Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung einer schmelzbaren heisshärtenden Zusammensetzung, umfassend mindestens ein Polymer mit isocyanatreaktiven Gruppen und mindestens ein an der Oberfläche desaktiviertes, festes Polyisocyanat, gekennzeichnet durch die Schritte a) Bereitstellung mindestens eines an der Oberfläche desaktivierten festen Polyisocyanats (A), welches unter den Reaktionsbedingungen bei den Schritten a) und b) inert ist; b) Dispergieren des mindestens einen Polyisocyanats (A) in mindestens einer Komponente (B), ausgewählt aus der Gruppe bestehend aus Monomeren, Oligomeren, Prepolymeren und niedermolekularen Polymeren mit funktionellen Gruppen (b'), unter Erhalt einer Reaktionsmischung (i); c) Zugabe einer Reaktionsmischung (ii) umfassend mindestens eine Komponente (C), ausgewählt aus der Gruppe bestehend aus Monomeren, Oligomeren, Prepolymeren und niedermolekularen Polymeren mit funktionellen Gruppen (c'), zur Reaktionsmischung (i), wobei durch die Reaktion der Komponenten (B) und (C) mindestens e