In 2007, Borówko et al. reported high-quality density profiles of neutral PBs using MC simulations, which are widely used for benchmarking in other theoretical works. However, when the grafting density is high, a subtle deviation between the PDFT and MD simulation is found for the monomers far from the surface. This deviation is not surprising because some approximations are introduced into the PDFT as well as the MD simulations. For example, Similar structural characteristics are captured for those two partially charged PBs shown in Figure . A dramatic decline in the density profiles of the second monomer is observed. This sharp peak is formed because the second monomer connected to the grafted monomer is tightly confined within its maximum stretching height. Owing to the wider accessible space of the monomer farther away from the grafted monomer, we naturally capture a peak with a lower amplitude and a greater distance from the surface. Especially, the end monomers (i.e., the 10 th monomer) distributes over the entire brush region, which determines the effective interfacial functional layer. As a consequence, the density profile of the monomer far from the grafted end evolves to a parabolic shape, which is different from the sharp curve of the second monomer. Additionally, though the counterions can freely move in entire space. Its density profiles show that most of counterions are concentrated within the PB layer due to the direct Coulomb interactions.