Anisotropic mechanical behaviour anisotropy

During the course of these and related studies, notably those concerned with the temperature dependence of the mechanical anisotropy and the identification of relaxation processes in structural terms, it became apparent that the aggregate model was successful in low density polyethylene because it described effectively the influence of the very anisotropic x-relaxation process on the mechanical behaviour. Stachurski and Ward were even able to extend the aggregate model to deal with the anisotropy of dynamic loss factor. (See Chapter 9 for further discussion.) It was, however, more in the spirit of the original conception of the aggregate model that it would deal with mechanical anisotropy in glassy polymers, where morphology was of secondary importance. 

Although the anisotropy of conductivity in metallic oriented-]CH) or PPV-H2SO4 samples is nearly 100, the behaviour of the MC is identical whether the current is parallel or perpendicular to the chain axis. This suggests that high quality oriented conducting polymers behave as anisotropic three-dimensional systems in which the charge transport mechanism is nearly identical in both parallel and perpendicular directions to the chain axis. 

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