We investigated the problem of adsorption of a single semiflexible polymer chain on to a planar, homogeneous surface using off-lattice Monte Carlo simulations. Adsorption characteristics were studied at different temperatures for chains of various stiffnesses. We have found that the stiffer chains adsorb more onto the surface and the adsorption transition takes place at a higher temperature when compared to that of the flexible chains. As stiffness increases, the adsorption transition is found to be sharper. The computed persistence length is found to grow linearly for small values of the bending energy, while for higher values, it shows a square root dependence. In the ground state, the parallel size of the stiffer chain is found to be much larger than that of the corresponding flexible polymer chain. The classical scaling laws for the flexible chains were tested for the stiffer chains and found that they are well obeyed, indicating that the universal properties of the chain measured over its whole dimension are unaffected by the local stiffness of the chain.

We report on results from Monte Carlo simulations of a single random copolymer adsorbed on a homogeneous planar surface. Although the critical crossover exponent is unaltered with respect to the case of homogeneous polymers, it is found that the scaling behavior is changed by the fraction of adsorptive monomers of the chain. In particular, we present some explicit expressions for energy and radius of gyration at low temperatures.

The adsorption transitions of a single self-avoiding polymer chain at chemically heterogeneous surfaces have been investigated using Monte Carlo methods and analyzed using scaling arguments. Evidence is provided that the crossover exponent φ, characterizing the transition between the weakly and the strongly adsorbed states, depends linearly on the dilution 0.6⩽p⩽1 of adsorbing sites on the surface, φ(p)≈0.35+0.2p. The transition temperatures of chains of length N scale according to Tc(N,p)/Tc(∞,p)∼N−φ(p). In particular, we have analyzed the adsorption energies and the parallel and perpendicular components of the end-to-end distance.

The results of Monte Carlo simulations carried out on a system of multiblock copolymers having two different types of monomer units adsorbed on checker board surface configurations are presented here. We investigated the adsorption behavior for a series of different chess board square dimensions and also for various block lengths of the copolymer. We find that the specific heat capacity curves for adsorption indicate double peaks showing a two stage pattern recognition of the copolymer on the surface. It is also seen that the transition that happens at lower temperature corresponds to pinning where the junction point of the different blocks gets pinned to the interface between the different surface sites. It is interesting to see that the multiblock copolymers form multiple pinning sites on the boundary between different kinds of surface sites. There exists an intermediate size of the square on the board where the recognition and pinning are most favored and for smaller and larger size of the board and block length, the adsorption proceeds like in homopolymer on homogeneous surfaces. Unlike in the case of the simplest model of diblock copolymer on stripe-patterned surfaces [K. Sumithra and E. Straube, J. Chem. Phys. 125, 154701 (2006)], here the recognition is stronger and the average adsorption energy and the perpendicular component of the radius of gyration show distinct changes corresponding to the two transitions. The conformational properties of the multiblock copolymer near the checkered surface show interesting effects with the perpendicular component showing strong deviations from the standard behavior.

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