Wide-Line Deuterium Nuclear Magnetic Resonance Studies of N-Deuterated Nylon-6, Nylon 11 and N-Normal Propyl Stearamide
Polymers and High Performance Materials
Deuterium-labelled nylon 6, nylon 11 and model compound, N-n-propyl stearamide, were synthesized and characterized by solid-state deuterium nuclear magnetic resonance (n.m.r.). Previous characterization of nylon 11 by X-ray, thermal and n.m.r. methods has provided information about the Brill transition, a reversible solid-solid crystal transition. Solid-state deuterium n.m.r. is a valuable complimentary technique for examining the molecular dynamics of such transitions. Selective deuteration on the nitrogen was accomplished using acylation with trifluoroacetic anhydride followed by precipitation and deacylation in deuterium oxide. Deuterium spectra of the crystalline component of nylon 11 indicate that there is no significant increase in motion of the N-H-2 bond occurring during the crystal-crystal (Brill) transition. Nylon 6 and N-n-propyl stearamide data also do not show significant motional transitions or changes with increasing temperature, and maintain rigid hydrogen-bonded lattices up to their melting points.
Mathias, L. J.
(1991). Wide-Line Deuterium Nuclear Magnetic Resonance Studies of N-Deuterated Nylon-6, Nylon 11 and N-Normal Propyl Stearamide. Polymer Communications, 32(11), 332-335.
Available at: http://aquila.usm.edu/fac_pubs/7055