Natural abundance 15n solid‐state nmr study of nylon‐6 in blends

Natural abundance solid‐state nuclear magnetic resonance spectroscopy (NMR) of nitrogen‐15 (¹⁵N) was applied to investigate the films of nylon‐6 and their blends with poly(propylene oxide) (PPO). The NMR ¹⁵N results allowed us to identify the crystalline forms present in these blends and also confirmed the previous NMR results obtained by ¹³C‐NMR study. From all NMR data the antiplasticization phenomena and plasticization effects caused by PPO content, in the blends were characterized. The polyoxide action is a function of its proportion. However, because the samples were prepared by solution casting, the residual solvent action cannot be ignored. The ¹⁵N chemical shift changes were influenced by both PPO and residual solvent. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3872–3875, 2003