A Novel Polyamide 12 Polymerization System and its Use for a LCM-process to Produce CFRP

Abstract

The aim of this study was to investigate the scope of the recently developed polymerization molding system for polyamide 12 (PA12), especially with respect to the formation of carbon fiber-reinforced PA12 composites. Initial screening of PA12 composite formation was performed by means of an internal mixer in order to identify the suitable type of surface-treated carbon fiber (CF). The content of residual lauryllactam (LL) monomer reflected the influence of the CF-treatment on the polymerization molding involving anionic in situ polymerization of LL. The cryogenic fracture surfaces were analysed by scanning electron microscopy (SEM) in order to evaluate the adhesion quality between the components. Finally, a bench-scale polymerization molding process was established successfully for the fabrication of multi-axial laminates. Macromechanical tests and dynamic mechanical thermo-analysis (DMTA) indicated that the performance of the new polymerization molding process is very similar to that of state-of-the-art PA12/CF composites.

Keywords

polymerization molding PA12 carbon fiber sizing liquid impregnation

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