Transition from highly to fully stretched polymer brushes in good solvent

The stretching of brushes of long polymers grafted to a planar surface is investigated by Monte Carlo simulations in the limit of very high grafting densities, as achieved in recent experiments. The monomer density profiles are shown to deviate considerably from the parabolic limiting form predicted by self-consistent field theory. A rapid transition is observed from parabolic to fully stretched polymers, characterized by a dramatic change in the end-monomer height distribution and by a clear crossover in the slope of the brush height versus scaled grafting density.