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Spinodal-assisted crystallization in polymer melts

Peter D. Olmsted·Wilson C. K. Poon·T. C. B. McLeish·N. J. Terrill·A. J. Ryan
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Abstract

Recent experiments in some polymer melts quenched below the melting temperature have reported spinodal kinetics in small-angle X ray scattering before the emergence of crystalline structure. To explain these observations we propose that the coupling between density and chain conformation induces a liquid-liquid binodal within the equilibrium liquid--crystalline solid coexistence region. A simple phenomenological theory is developed to illustrate this idea, and several experimentally testable consequences are discussed. Shear is shown to enhance the kinetic role of the hidden binodal.

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Peter D. Olmsted, Wilson C. K. Poon, T. C. B. McLeish, N. J. Terrill, A. J. Ryan. 1998-06-02. Spinodal-assisted crystallization in polymer melts. https://doi.org/10.1103/physrevlett.81.373

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