Polycaprolactam depolymerization

CL must be very carefully purified to exclude small concentrations of (1) ferric ions which would catalyze die thermal oxidative degradation of polycaprolactam and (2) aldehydes and ketones which would markedly increase oxidizability of CL. The impurities in CL may retard die rate of CL polymerization as well as having a harmful effect on die properties of die polymer fiber. In die vacuum depolymerization of nylon-6, a catalyst must be used because in die absence of a catalyst by-products such as cyclic olefins and nitrides may form, which affects the quality of die CL obtained.1... 

The thermal depolymerization of polycaprolactam is explained by processes of hydrolysis [12], acidolysis, and aminolysis [11, 12]. 

The depolymerization of polycaprolactam can occur not only from the ends of the chain, but also at any portion of the chain, as a result of reactions of intramolecular exchange [8, 9] ... 

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