The number and weight average molecular weights (M n and M w ) as well as the polydispersity index (PDI) of virgin PA 6 filaments and recovered PA 6 samples were measured and the results summarized in Table (S6, S7) †. When comparing the molecular weights of samples from experiments with different CEW compositions or different methods of energy supply under otherwise identical experimental conditions there is no clear trend observable from the data. We therefore conclude that the CEW composition and the method of energy supply do not have an effect on the molecular mass distribution of the recovered PA 6. When comparing the molecular weights of samples from experiments with different dissolution times under otherwise identical experimental conditions the values for long dissolution times are slightly higher than those for shorter times. We attribute this increase in molecular weight to a possible, appreciable, autonomous condensation reaction that even protects against the downcycling of the polymer. However, this observation is in contradiction with the studies where a prolongation of dissolution time was reported to lead, if anything, to a decrease in molecular weight . Ideally, the molecular weight distribution of a polymer should remain unchanged throughout a dissolution-precipitation cycle to preserve its properties. In table 4, relative changes in M n and M w are summarized for dissolution-precipitation processes found in literature. This change is expressed as the molecular weight of the recovered sample in relation to that of the virgin material, with an ideal value being 100%. To the best of our knowledge, there is no consensus on a tolerable change. In some studies, values of 64% are considered negligible , while in other cases changes beyond 10% are deemed unacceptable . Into this context we present our measured values claiming that PA 6 -independently of energy supply, CEW composition or heating time -mostly underwent dissolution rather than chain scission during the treatment. This claim is fully in line with Qianhui et al. (2023) observing no molecular degradation of PA 6 in CEW.