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arXiv · 2009.05281

Phase behavior of correlated random copolymers

Elena Patyukova·Erte Xi·Mark R. Wilson
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Abstract

In this work, Flory-Huggins phase diagrams for correlated random copolymers with realistic chain lengths are calculated. This is achieved in two steps. At first we derive a distribution function of copolymer chains with respect to composition and blockiness. Then we used the method of moments, which was developed by Sollich and Cates [Sollich, P.; Cates, M. E.; Phys. Rev. Lett. 1998, 80, 1365-1368] for polydisperse systems, to reduce the number of degrees of freedom of the computational problem and calculate phase diagrams. We explored how location of transition points and composition of coexisting phases depend on copolymer composition, blockiness and degree of polymerisation. The proposed approach allows to take into account fractionation, which was shown to have effect on the appearance of phase diagrams of statistical copolymers.

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Elena Patyukova, Erte Xi, Mark R. Wilson. 2020-09-11. Phase behavior of correlated random copolymers. https://doi.org/10.1021/acs.macromol.0c02840

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