Introducing thermoplastics to serial production: Thermoplastic resin transfer molding using caprolactam

Abstract

In order for thermoplastics to compete with thermosets in terms of fast production cycles, KraussMaffei improved a thermoplastic RTM process with a three-component dosage unit where the low-viscosity chemical precursor of polyamide 6, called caprolactam, is mixed with an activator/catalyst and therefore in-mold polymerized to create near net shape polyamide 6 parts. Within the project CosiMo, a series of tests was conducted at the German Aerospace Center in Augsburg, using different semi-finished products (woven carbon fibre, non-woven glass fibre, pure resin). Dielectric sensors which in-situ tracked the viscosity helped to evaluate the reaction evolution and to monitor the overall process.