Hardenable compositions based on silylated polyurethanes

Abstract

The invention relates to a method for producing cross-linkable formulations. In a first step of the method, at least one alpha, omega-difunctional organic polymer of formula (1) X-A-X (1) is converted into organyloxysilyl-terminated polymers P1, using organofunctional silanes of formula (2) Y-R-Si-(R1)m(-OR2)3-m (2) in the presence of catalysts (A) selected from the group consisting of potassium,iron, indium, zinc, bismuth and copper compounds. In said formulae, R is a bivalent, optionally substituted hydrocarbon group which comprises between 1 and 12 carbon atoms and can be interrupted withheteroatoms, R1 and R2 are the same or different, monovalent, optionally substituted hydrocarbon groups which comprise between 1 and 12 carbon atoms and can be interrupted with heteroatoms, A is a bivalent, optionally substituted hydrocarbon group which comprises at least 6 carbon atoms and can be interrupted with heteroatoms, m is equal to 0, 1 or 2, X is a hydroxyl group, and Y is an isocyanategroup, or X is an isocyanate group and Y is a hydroxyl group or a primary or secondary amino group. In a second step, the polymers P1 obtained in the first step are mixed with a silane condensation catalyst (B) selected from the group consisting of compounds of elements of the third main group and / or fourth secondary group and heterocyclic organic amines, amine complexes of the element compounds,or the mixtures thereof. Optionally, said mixture is mixed with other substances (C). The formulations do not contain organic tin compounds, and are suitable for using as adhesives, sealants or coating agents.

Description

technical field [0001] The present invention relates to a process for the manufacture of silane crosslinked curable compositions and their use in adhesives and sealants and coatings. Background technique [0002] Polymer systems having reactive alkoxysilyl groups are known. In the presence of atmospheric moisture, these alkoxysilane-terminated polymers are already capable of polycondensation with one another at room temperature, releasing alkoxy groups. Depending on the concentration of alkoxysilyl groups and their structure, mainly long-chain polymers (thermoplastics), relatively wide-mesh three-dimensional networks (elastomers), or highly cross-linked systems (thermosets) are formed . [0003] Polymers generally comprise an organic backbone terminated with alkoxysilyl groups. The organic backbone may include, for example, polyurethane, polyester, polyether, and the like. [0004] For many years, one-component moisture-curing adhesives and sealants have played an import...

AI Technical Summary

Problems solved by technology

However, the mechanical properties of adhesives and sealants based on these prepolymers are unsatisfactory, especially with regard to their elongation and breaking strength

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