Thermodynamics of Densely Grafted Strong Polyelectrolyte Brushes in the Swollen State

摘要

The possibility of controlling the physical and chemical properties of surfaces by means of neutral and charged polymer brushes has attracted great attention in both, industry and academia in the past decades. In most applications1,2 , a solvent is present and if the solvent quality is high, the chains stretch in order to increase the polymer- solvent interactions and thus reduce the enthalpy of the system. For strong polyelectrolytes, where the number of charges is fixed this effect is even larger because of the electrostatic repulsion between chain segments. This stretching causes a very high entropy loss in the system which can even provoke scission of carbon-carbon bonds as shown by Sheiko et al. in order to reduce the overall free energy of the system.