A method for analysing proton NMR relaxation data from motionally heterogeneous polymer systems

Historically, the results of studies of the motional processes present in polymers above the glass transition temperature (T-g) by proton NMR spin-lattice relaxation in either the laboratory or rotating frames (T-1 or T-1p) have shown poor agreement with the results from similar studies carried out using other techniques such as dielectric or mechanical relaxation. We believe that this is mainly because of the complication of the NMR results due to magnetisation transport, either by spin diffusion or by bulk diffusion of the polymer. We suggest a novel approach to the analysis of proton NMR relaxation data from a motionally heterogeneous polymer, and show that the results of such an analysis are intrinsically reasonable and of the form expected for dielectric or mechanical relaxation. (C) 1998 Elsevier Science B.V. All rights reserved.