Are polymer melts "ideal"?

Abstract

It is commonly accepted that in concentrated solutions or melts high-molecular weight polymers display random-walk conformational properties without long-range correlations between subsequent bonds. This absence of memory means, for instance, that the bond-bond correlation function, $P(s)$, of two bonds separated by $s$ monomers along the chain should exponentially decay with $s$. Presenting numerical results and theoretical arguments for both monodisperse chains and self-assembled (essentially Flory size-distributed) equilibrium polymers we demonstrate that some long-range correlations remain due to self-interactions of the chains caused by the chain connectivity and the incompressibility of the melt. Suggesting a profound analogy with the well-known long-range velocity correlations in liquids we find, for instance, $P(s)$ to decay algebraically as $s^{-3/2}$. Our study suggests a precise method for obtaining the statistical segment length \bstar in a computer experiment.

4 pages, 3 figures

References in corpus (2)

• Long Range Bond-Bond Correlations in Dense Polymer Solutions
• Single chain structure in thin polymer films: Corrections to Flory's and Silberberg's hypotheses

Cited by in corpus (4)

• Intramolecular long-range correlations in polymer melts: The segmental size distribution and its moments
• Scale-free static and dynamical correlations in melts of monodisperse and Flory-distributed homopolymers: A review of recent bond-fluctuation model studies
• A finite excluded volume bond-fluctuation model: Static properties of dense polymer melts revisited
• Distance dependence of angular correlations in dense polymer solutions