How does the pattern of grafting points influence the structure of one-component and mixed polymer brushes?

Using Monte Carlo simulations of a coarse-grained bead-spring model we study the lateral structure formation of one-component polymer brushes in a bad solvent and of a mixed polymer brush upon increasing the incompatibility of the two species. We compare the morphology of the brush with a regular distribution of grafting points and with a random arrangement. Density or composition fluctuations of the grafting points enhance the formation of irregular structures but randomness prevents the formation of long-range order. Even small fluctuations of the grafting points are sufficient to pin the lateral structures of the brush.