Interaction between highly compressed brushes of hard-sphere chains

The behavior of compressed polymer brushes composed of hard-sphere chains are investiaged with the excluded volume interactions among the chain segments treated by using a classical density functional theory (DFT). For the brush-brush compressing systems, an obvious interpenetration zone can be observed. The extent of the interpenetration depends strongly on the grafting density. Furthermore, the repulsive force between the brush and wall or between the two brushes has been obtained as a function of the compression distance. Compared to the prediction of the analytic self-consistent field theory, such force increases more rapidly in the brush-wall compression with high polymer grafting densities or at higher compressions.