Temperature dependence of the dynamics of methylene chains in aliphatic nylons of different chain length

Temperature-dependent inelastic neutron backscattering experiments with mu eV energy resolution on nylons of different chain length show the onset of dynamic processes on the time scale of 10(-8) s far below T-g, around 200 K . The evaluation in terms of non-Gaussian vibrations reveals an apparent me an square displacement which increases with the chain length. It is similar for nylon 6, 46 and 66, but shows lower values for nylon 3 and much larger mean square displacements for nylon 12, (C) 2000 Elsevier Science B.V. All rights reserved.