Process for the production of storage-stable polyurethane prepregs and mouldings produced therefrom from dissolved polyurethane composition

A process of producing a prepreg, the process comprising, in the following order:

• directly impregnating a fibrous support with a solution comprising a reactive polyurethane composition and a solvent, to obtain a prepreg intermediate;
• and then
• removing the solvent from the prepreg intermediate at a temperature less than 100° C., to obtain a prepreg comprising the fibrous support and a crosslinkable matrix comprising the reactive polyurethane composition and less than 0.5% by weight of the solvent,
• wherein the reactive polyurethane composition comprises (1) a polymer comprising a functional group reactive towards an isocyanate and (2) at least one internally blocked di- or polyisocyanate,
• wherein the polymer comprising a functional group reactive towards an isocyanate functions as a binder and is at least one member selected from the group consisting of polyesters, polyacrylates, and polycarbonates,
• wherein the internally blocked di- or polyisocyanate functions as a curing agent, and
• wherein the matrix in the prepreg is not crosslinked.