Evolution of phase diagrams of polymer adsorption over attractive surfaces as a function of flexibility and solvent quality

We describe the equilibrium conformations of a polymer near an attractive surface for different conditions in solvent quality and polymer stiffness. Using molecular dynamics techniques in a canonical ensemble, we show the evolution of the phase diagrams as function of temperature and surface interaction strength. Phase diagrams show an ampler variety of possible conformations due to changes in solvent quality compared to stiffness for which variations in conformations appear mainly in the degree of adsorption. We show that the adsorption transition is independent of solvent quality and stiffness. When both parameters change simultaneously, solvent effects are stronger than the stiffness secluding the stiff conformations to regions of low temperature and high surface attraction. A remarkable observation is that the radius of gyration perpendicular component to the surface, R-gx, signals the adsorption transition at coincidental points for each system independently of solvent and stiffness variations in all simulations, which may be of aid in locating this transition in other systems.

Automated summary

In this study, we investigate the equilibrium conformations of a polymer near an attractive surface under different solvent quality and polymer stiffness conditions. Our results show that changes in solvent quality have a greater impact on the conformational variety compared to stiffness, mainly affecting the degree of adsorption. We also find that the adsorption transition is independent of both solvent quality and stiffness. Interestingly, the perpendicular component of the radius of gyration to the surface, R-gx, serves as a consistent indicator for the adsorption transition in all simulations, regardless of solvent and stiffness variations, which may aid in locating this transition in other systems.