Modeling of higher cyclic oligomer formation in nylon 6 polymerization

Abstract

A detailed model incorporating mass balance and moment equations and appropriate closure conditions is developed for nylon 6 polymerization. This accounts for the formation of the major reaction products (polymer) as well as the undesirable side products, namely, cyclic oligomers. The concentrations of the individual lower-order cyclic oligomers and also the weight fraction of the total cyclics can be predicted under different conditions of reaction. Model parameters have been evaluated by an optimal curve-fitting technique, using experimental results available in the open literature. The most sensitive of these parameters is also identified. This new model can be used for better design and optimization of industrial nylon 6 reactors.