Entangled polymer dynamics

As we conjectured in the introduction, the fundamental role of topology in this approach to entangled polymer dynamics would indicate that changes to the topology of the molecules themselves would radically affect the dynamic response of the melts. In fact rheological data on monodisperse star-branched polymers, in which a number of anionically-polymerised arms are coupled by a multifunctional core molecule, pre-dated the first application of tube theory in the presence of branching [22]. Just the addition of one branch point per molecule has a remarkable effect, as may be seen by comparing the dissipative moduli of comparable linear and star polymer melts in Fig. 5. 

All the discussions of entangled polymer dynamics above were limited to linear chains. The molecular architecture of the chain (star vs. linear vs. 

Entangled polymer dynamics 9.5.1 Relaxation times and diffusion... 

McLeish, T.C.B., 2002. Tubetheory of entangled polymer dynamics. Adv. Phys. 51 (6), 1379-1527. Mergell, B., Everaers, R., 2001. Tube models for rubber-elastic systems. Macromolecules, 34 (16), 5675-5686. 

McLeish, T. C. B. 2002. Tube theory of entangled polymer dynamics. Adv. Phys. 51 1379-1527. 

Obviously, if >4 the memory function is slowly decaying, and there is no limit in which a Markovian approximation would be applicable. Therefore the renormalization order =3 is the boundary between fast and slowly decaying memory functions. That is, renormalization attempts to describe entangled polymer dynamics are realistically restricted to the RRM, TRRM or the ThRRM without any heuristic preference. 

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