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Localization of a multiblock copolymer at a selective interface: Scaling predictions and Monte Carlo verification

Andrea Corsi·Andrey Milchev·Vakhtang G. Rostiashvili·Thomas A. Vilgis
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Abstract

We investigate the localization of a hydrophobic - polar (HP) - regular copolymer at a selective solvent-solvent interface with emphasis on the impact of block length $M$ on the copolymer behavior. The considerations are based on simple scaling arguments and use the mapping of the problem onto a homopolymer adsorption problem. The resulting scaling relations treat the gyration radius of the copolymer chain perpendicular and parallel to the interface in terms of chain length N and block size M, as well as the selectivity parameter χ. The scaling relations differ for the case of weak and strong localization. In the strong localization limit a scaling relation for the lateral diffusion coefficient D is also derived. We implement a dynamic off-lattice Monte - Carlo model to verify these scaling predictions. For chain lengths in a wide range (32 < N < 512) we find good agreement with the scaling predictions.

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Andrea Corsi, Andrey Milchev, Vakhtang G. Rostiashvili, Thomas A. Vilgis. 2004-11-16. Localization of a multiblock copolymer at a selective interface: Scaling predictions and Monte Carlo verification. https://doi.org/10.1063/1.1854133

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