Process for producing compound materials with a polylactam matrix which can be thermally postformed

A process for producing a postformable composite matrix of polylactam and a reinforcing fiber structure, said process comprising:

• providing a liquid system for anionic polymerization of a lactam, said liquid system comprising an activator, a catalyst and optional additives,
• providing an anhydrous lactam melt separate from said liquid system,
• homogeneously admixing said liquid system and said anhydrous lactam melt to provide a low-viscosity mixture,
• impregnating and embedding a reinforcement fiber structure with said low-viscosity mixture during initial polymerization of said lactam melt to provide an impregnated fiber structure, and
• further polymerizing said lactam melt by anionic polymerization and shaping said impregnated fiber structure.