Characterization of recycled polyamide-6 irradiated by electron beams

This work had the objective to characterize recycled polyamide-6 irradiated by a 1.5 MeV electron beam for different doses. The recycling process needs special attention, because successive recycling cycles promote changes in several properties of the material, as structures break down, decrease of molecular weight, increase of melting index and decrease of mechanical resistance. The thermal properties of the recycled polyamide-6 were investigated by DSC and DMA measurements. The density of crosslinking was calculated through the equilibrium swelling experiments, using the Flory-Rehner theory. The mechanical properties by the stress strain. From the experimental results, it was shown that for doses up to 500 kGy, at 22.61 kGy/s dose rate, in the presence of air, the recycled polyamide-6 undergoes the crosslinking process through micro network formation. For doses from 600 to 1000 kGy, the degradation process is predominant. (author)