Influence of reprocessing on the mechanical properties of polyamide 6 containing talc

In this study, polyamide 6 containing 30wt% talc was reprocessed via injection molding up to eight processing cycles. The effects of reprocessing on the mechanical properties and on the melt viscosity were analyzed by flexural and impact tests and by melt flow index (MFI) tests, respectively. Flexural strength and modulus remained unchanged up to the 5th processing cycle. From the 6th processing cycle, flexural strength and modulus decrease with increasing processing cycles. Similar trend was observed for impact strength, however, the decrease observed in this property was much lower. From the 6th processing cycle, MFI increases with increasing processing cycles, indicating a possible reduction in PA6 molar mass.