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Density functional theory and demixing of binary hard rod-polymer mixtures

P. Bryk
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Abstract

A density functional theory for a mixture of hard rods and polymers modeled as chains built of hard tangent spheres is proposed by combining the functional due to Yu and Wu for the polymer mixtures [J. Chem. Phys. {\bf 117}, 2368 (2002)] with the Schmidt's functional [Phys. Rev. E {\bf 63}, 50201 (2001)] for rod-sphere mixtures. As a simple application of the functional, the demixing transition into polymer-rich and rod-rich phases is examined. When the chain length increases, the phase boundary broadens and the critical packing fraction decreases. The shift of the critical point of a demixing transition is most noticeable for short chains.

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P. Bryk. 2003-10-31. Density functional theory and demixing of binary hard rod-polymer mixtures. https://doi.org/10.1103/physreve.68.062501

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