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Competition of Mesoscales and Crossover to Tricriticality in Polymer Solutions

M. A. Anisimov·A. F. Kostko·J. V. Sengers
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Abstract

We show that the approach to asymptotic fluctuation-induced critical behavior in polymer solutions is governed by a competition between a correlation length diverging at the critical point and an additional mesoscopic length-scale, the radius of gyration. Accurate light-scattering experiments on polystyrene solutions in cyclohexane with polymer molecular weights ranging from 200,000 up to 11.4 million clearly demonstrate a crossover between two universal regimes: a regime with Ising asymptotic critical behavior, where the correlation length prevails, and a regime with tricritical theta-point behavior determined by a mesoscopic polymer-chain length.

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M. A. Anisimov, A. F. Kostko, J. V. Sengers. 2002-01-14. Competition of Mesoscales and Crossover to Tricriticality in Polymer Solutions. https://doi.org/10.1103/physreve.65.051805

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