On the Adsorption of Two-State Polymers

TL;DR

This study uses Monte Carlo simulations to show that two-state copolymers with interconverting monomers adsorb similarly to homopolymers, with adsorption characteristics influenced by bulk and surface equilibrium constants, while the crossover exponent remains unchanged.

Contribution

It demonstrates that annealed two-state copolymers adsorb as homopolymers with an effective energy dependent on PH equilibrium constants, providing a theoretical and simulation-based understanding.

Findings

Adsorption behavior matches the effective energy model.

Surface potential shape does not alter the crossover exponent.

PH ratios at surface and bulk agree with theoretical predictions.

Abstract

Monte Carlo(MC) simulations produce evidence that annealed copolymers incorporating two interconverting monomers, P and H, adsorb as homopolymers with an effective adsorption energy per monomer, $\epsilon_{eff}$, that depends on the PH equilibrium constants in the bulk and at the surface. The cross-over exponent, $\Phi,$ is unmodified. The MC results on the overall PH ratio, the PH ratio at the surface and in the bulk as well as the number of adsorbed monomers are in quantitative agreement with this hypothesis and the theoretically derived $\epsilon_{eff}$. The evidence suggests that the form of surface potential does not affect $\Phi$ but does influence the PH equilibrium.