| 摘要 |
The invention relates to methods for producing storage-stable, latent-reactive layers and powders of surface-deactivated, solid polyisocyanates and dispersions or aqueous solutions of isocyanate reactive polymers, which can be used as adhesives and coverings. Said dispersions, suspensions or aqueous solutions can applied to a substrate in an appropriate form. Water can then be eliminated at a temperature inferior to the reaction temperature of the isocyanates and this operation can take place at a temperature above the softening temperature of the polymers. This process produces, at ambient temperature, dry and substantially water free layers which are storage stable and can react with the polymers at the polyisocyanate reaction temperature. The influence of temperatures above the reaction temperature of the surface-deactivated, solid polyisocyanates results in production of layers which are cross-linked to the functional groups of the polymer through reactions, said layers displaying high heat-resistance, and high chemical storage stability. These latent-reactive products in layer or powder form can be used for manufacturing glued assemblies and coverings.
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