Composite semifinished products and mouldings produced therefrom and directly produced mouldings based on hydroxy-functionalized (meth)acrylates and uretdiones which are crosslinked by means of radiation to give thermosets

The invention relates to a process for producing polyurethane prepregs which are stable during storage, and to mouldings (composite components) produced therefrom. The prepregs or components are produced by mixing, for example, (meth)acrylate monomers, (meth)acrylate polymers, hydroxy-functionalized (meth)acrylate monomers and/or hydroxy-functionalized (meth)acrylate polymers with uretdione materials. Optionally, photoinitiators can also be added. This mixture or solution is applied by known processes to fibre material, e.g. carbon fibres, glass fibres or polymer fibres, and is polymerized with the aid of radiation or plasma applications. Polymerization, e.g. at room temperature or at up to 80 DEG C, gives thermoplastics or, respectively, thermoplastic prepregs which can subsequently be subjected to forming processes. By using elevated temperature, the hydroxy-functionalized (meth)acrylate constituents can then be crosslinked with the uretdiones already present in the system. It is thus possible to produce dimensionally stable thermosets and, respectively, crosslinked composite components.