NMR parameters and material properties

Transition parameters can be determined directly through the analysis of the time evolution of changes in NMR images, whereas state parameters must be related to NMR 

Transition parameters and kinetic parameters characterizing Physical ageing Chemical ageing 

Vulcanization and curing processes Concentration changes in chemical reactions Thermal heating under load Fluid permeation, drying 

A simple model of an elastomer network is depicted in Fig. 7.1.8. The segmental motion of inter-cross-link chains is fast but anisotropic at temperatures of 100-150 K above the glass transition temperature The end-to-end vector R of such a chain reorients on a much slower timescale because it appears fixed between seemingly static cross-link points. As a result of the fast but anisotropic motion, the dipolar interaction between spins along the cross-link chains is not averaged to zero, and a residual dipolar coupling remains [Cohl, Gotl, Litl]. 

The simple model of Fig. 7.1.8 is often extended to include dangling chain ends and possibly even a sole part [Kuhl, Menl, Siml]. Neglecting the sole part, T2 is assigned to the rapidly moving segments of the cross-link chains, and relaxation of the slowly moving cross-links is described by the associated correlation time Tj. Based on the 

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