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arXiv · 0912.3340

Distance dependence of angular correlations in dense polymer solutions

J. P. Wittmer·A. Johner·S. P. Obukhov·H. Meyer·A. Cavallo·J. Baschnagel
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Abstract

Angular correlations in dense solutions and melts of flexible polymer chains are investigated with respect to the distance $r$ between the bonds by comparing quantitative predictions of perturbation calculations with numerical data obtained by Monte Carlo simulation of the bond-fluctuation model. We consider both monodisperse systems and grand-canonical (Flory-distributed) equilibrium polymers. Density effects are discussed as well as finite chain length corrections. The intrachain bond-bond correlation function $P(r)$ is shown to decay as $P(r) \sim 1/r^3$ for $ξ\ll r \ll \r^*$ with $ξ$ being the screening length of the density fluctuations and $r^* \sim N^{1/3}$ a novel length scale increasing slowly with (mean) chain length $N$.

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J. P. Wittmer, A. Johner, S. P. Obukhov, H. Meyer, A. Cavallo, J. Baschnagel. 2009-12-17. Distance dependence of angular correlations in dense polymer solutions. https://doi.org/10.1021/ma902299h

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