Melting behavior of nylon 6 fiber in textiles

The melting process of constrained nylon 6 fibers has been studied to estimate the true melting point of its original crystals. The melting peak became simpler in shape and shifted to higher temperature with increasing fiber-axis restricting force. When heating rate, beta, was increased, the temperature where the melting curve initially departs from its baseline, T-sm, decreased steeply in the range of 45 to 60degreesC min', and increased linearly with increasing beta above 60degreesC min(-1). By linear extrapolation of T-sm to 0degreesC min(-1), the temperature of ca 190degreesC was obtained for the melting temperature of the original nylon 6 crystals. This seems to correspond to the zero-entropy-production melting of the most imperfect crystallites of the nylon 6 fabric.