Force-induced desorption of copolymeric comb polymers

EJ Janse van Rensburg; CE Soteros; SG Whittington

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arXiv · 2311.09320

Force-induced desorption of copolymeric comb polymers

EJ Janse van Rensburg·CE Soteros·SG Whittington

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Abstract

We investigate a lattice model of comb copolymers that can adsorb at a surface and that are subject to a force causing desorption. The teeth and the backbone of the comb are chemically distinct and can interact differently with the surface. That is, the strength of the surface interaction can be different for the monomers in the teeth and in the backbone. We consider several cases including (i) the uniform case where the number of teeth is fixed and the lengths of the branches in the backbone and the lengths of the teeth are all identical, (ii) the case where the teeth are short compared to the branches in the backbone, (iii) the situation where the teeth are long compared to the backbone, and (iv) the case where the number of teeth approaches infinity. We determine the free energies in the thermodynamic limit and discuss the nature of the phase diagrams of the model.

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EJ Janse van Rensburg, CE Soteros, SG Whittington. 2023-11-15. Force-induced desorption of copolymeric comb polymers. https://arxiv.org/abs/2311.09320

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