Neutron reflectometry is used to obtain a direct measurement of the monomer distribution of a weakly bound end-grafted polystyrene layer in equilibrium with bulk solution, as a function of the polymer concentration and temperature. We report for the first time two new regions in the density profile of the polymers, an excess polymer near the surface and a wetting layer on top of the brush. The physical properties of the polymer layer are strongly affected by the equilibrium between the bound and free polymer molecules.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)