Thermoplastic resin transfer molding of carbon fiber reinforced polyamide 6 composite with the improved processability using zeolite particle

Thermoplastic resin transfer molding (T-RTM) of polyamide 6-based composite is one of the promising process to mass-produce an environmentally friendly textile composite with recyclable thermoplastic resin, in which ε-caprolactam monomer with low viscosity is injected and in situ polymerized into the fabric. The side reactions caused by water in the anionic polymerization process of the monomer is a crucial problem for fabricating the composite with a high quality. In this study, we introduced zeolite, a porous ceramic water-absorbing particle, into the ε-caprolactam to improve the moisture sensitivity during the anionic polymerization. The selective water-absorbing effect of zeolite particle was verified by measuring the monomer conversion, viscosity-average molecular weight, and viscosity change during polymerization, and mechanical properties of the resultant carbon fiber reinforced polyamide composite were investigated. It is expected that processability of the T-RTM is remarkably improved by reducing both the drying time during process and quality deviation of the composite by variation of humidity, which can make T-RTM process a viable technology for mass-production of thermoplastic composites.