A new fiber‐sampling technique for infrared spectroscopy as applied to nylon 6 and poly(ethylene terephthalate)

Abstract A number of techniques have been used in the past for obtaining the infrared spectra of fine fibers. A new technique has been developed which overcomes many of the problems of previous methods. The present technique involves winding a single filament between two salt windows which are separated by a spacer which is the same or slightly greater in thickness than the fibers. This results in a layer of adjacent parallel fibers. Good‐quality polarized infrared spectra were obtained on oriented poly(ethylene terephthalate) and oriented nylon 6 fibers with the new technique. The data demonstrate the high level of “A” conformation orientation present in highly drawn nylon 6 fibers and the existance of chain folds in drawn poly(ethylene terephthalate) fibers. The structural changes which occur during the shrinkage of nylon 6 fibers are also demonstrated.