Topological interchain effects

Moreover, the ratios Tj/Xj obtained at different temperatures are similar to the values obtained for labell polybutadiene in dilute solution in toluene (= 30). Thus, the surrounding chains seem to affect local dynamics only at the level of the friction coefficient. Intrachain connectivity remains the essential non isotropic constraint on local dynamics in bulk polymers and models for the isolated chain are applicable. This is consistent with the idea that topological interchain effects only act on a... 

The behavior described by Equation 11.44 differs at a fundamental physical level from the behavior described by Equation 11.31 for the Gy of thermoplastics. As was discussed in Section ll.B.2.e, the chemical crosslinks do not typically have a strong effect on E, which is controlled mainly by interchain interactions on a more local length scale. On the other hand, the distance between the topological constraints created by the crosslinks in a typical thermoset is of a length scale that is relevant for yielding which defines the onset of plastic deformation. 

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