Method for producing composite fiber materials with a particularly low degree of fiber warpage

A process for producing a fiber composite material comprising a thermoplastic molding composition A as polymer matrix M, reinforcing fibers B, comprising the steps of

• i) providing at least one fabric F in the form of a weave composed of reinforcing fibers B treated with a silane size,
• ii) providing a thermoplastic molding composition A that serves as matrix M, having at least 0.3 mol %, based on component A, of a chemically reactive functionality in the form of functional monomers,
• iii) optionally incorporating at least one additive C into the thermoplastic molding composition A,
• iv) introducing the thermoplastic molding composition A that serves as matrix M into the at least one fabric F by embedding the thermoplastic molding composition A into the reinforcing fibers B by means of a relative movement in which the reinforcing fibers B remain immobile apart from a continuous or discontinuous one-dimensional production feed, and consolidating this composite composed of at least one fabric F and the matrix M,
• v) reacting the chemically reactive functionalities of the thermoplastic molding composition A with the polar groups at the surface of the reinforcing fibers B that have been treated with the silane size,
• vi) cooling the fiber composite material, and optionally further process steps,
• wherein the chemically reactive functionality of the thermoplastic molding composition A is based on components selected from the group of maleic anhydride, N-phenylmaleimide, and glycidyl (meth)acrylate, and steps iv) to vi) are conducted at a temperature of at least 150° C., and steps v) to vi) by pressing under elevated pressure.