Self supporting reactive hotmelt adhesive element and its use

摘要

Surprisingly, an isocyanate solid or liquid at room temperature, when embedded homogeneously in a reactive adhesive melt, e.g. a reactive self-supporting single component adhesive melt, shows so little room temperature activity towards the reactive functional groups of a polymer and/or resin matrix, and especially towards OH groups and water, that a fresh adhesive melt can be granulated under water. <??>Independent claims are included for: <??>(1) A process for preparation of a reactive adhesive melt by mixing the components, especially with light heating, without reaction of the individual components when the isocyanate is solid, and especially when these have been previously mixed in a mixer or extruder, with cooling and/or solidification, processing of the homogeneous mass thus obtained, to give a film, if necessary with slight heating above room temperature, without reaction of the individual components, cooling, of the film to room temperature, followed by further treatment, especially dimensioning and/or take up on rollers; <??>(2) (a) preparation of a first and second joint element, (b) deposition of the reactive adhesive melt element on the first of the two joint elements, especially with warming and/or under pressure, if necessary with melting of the reactive component, with initiation of a crosslinking process, (c) bonding together of the first and second joint elements with deposition of the second joint element on the side of the first joint element carrying the reactive adhesive melt, preferably under pressure, (d) pressing together of the first and second joint elements with heating and/or the action of moisture, and finally (e) curing, if necessary under pressure and/or heating and/or the action of moisture; <??>(3) (a) preparation of a first and second joint element and a reactive adhesive melt element, (b) joining of the first and second adhesive elements to the already aligned reactive adhesive melt, (c) pressing together of the two elements in step (b), especially with heating and if necessary the action of moisture, and (d) curing, if necessary under pressure and/or heating and/or the action of moisture; <??>(4) At least one catalyst, preferably homogeneous, distributed over the isocyanate reactive polymer (IRP) and embedded in it, is present, especially a currently available catalyst well known in polyurethane chemistry, espec ially one selected from: organic tin compounds, such as dibutyltin dilaurate (DBTL), alkylmercaptide compounds of dibutyltin or organic Fe, Pb, Co, Bi, Sb, and Zn compounds, and mixtures of the above compounds and amine based catalysts, such as the tertiary amine 1,4-diazabicyclo(2.2.2) octane and dimorpholineodiethyl ether and their mixtures, especially at a catalyst content of 0.01-5 wt.% relative to the reactive adhesive melt; <??>(5) a reactive adhesive melt composition containing (wt.%): isocyanate (0.5-30), IRP and/or resin (0-20), non-isocyanate reactive polymer, wax, and/or resin (0-60), catalysts (0.01-5), additive to improve heat conductivity and/or sensitivity to radiation (1-25, preferably 5-20).