Figure shows the quantitative influence of the H 2 O:EtOH molar ratio on the PA 6 recovery. We found that the compositions A, B, D and E dissolve significantly more PA than composition C. Specific investigations are essential to mechanistically declare the observed phenomenon. Although experiments using composition E had to be repeated often due to inaccuracies in the mass balances and the undissolved filaments stuck together more than in experiments using other compositions, composition E clearly gave the highest recovery of PA 6. This is why it was chosen for further investigations. A difference in the dissolution behaviour of PA 6 and PA 6.6 might be found since Rietzler et al. (2018) havealthough without further clarification -reported composition C to be the best dissolving composition for PA 6.6 fibers and Qianhui et al. (2023) used only composition C to dissolve PA 6.