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[EN] Dynamics of multilayer adsorption of macromolecules with different degree of polymerization is studied by coarse¿grained Monte Carlo simulations, focusing on both the interface macromolecule¿surface and chain¿chain interaction in and out of equilibrium conditions. The interfacial interaction between the solid flat surface and the macromolecules is modeled by means of a Lennard¿Jones potential, and inter¿ and intrachain interactions are simulated using bond angle, bond length, and Lennard¿Jones potentials. The results show that local and conformational motions near the glass transition temperature promote configurations with minimal energy, which induce better space efficiency and favor aligned conformations at the interface. In this context, it is also found that restriction of movement, together with the connectivity effect exerted by the partially adsorbed segments, leads to a range of chain lengths that maximizes the molecular groups adsorbed.

[EN] The kinetics of structural relaxation was simulated using the bond fluctuation model. Annealing of the system in the glassy state produces a clearly nonexponential decrease in the energy in a certain temperature interval. At lower temperatures, the decrease in energy takes place by successive small steps, due to the change of the energy of individual polymer chains that modify their conformation into small neighbourhoods. This cooperativity is behind the nonexponential behaviour shown by structural relaxation at higher temperatures. A second order Markov chain is able to reproduce the nonexponentiality with quite good agreement with the bond fluctuation simulated curves. Cooperativity comes from the fact that the transition probability of a polymer chain between two energy levels depends on the history of previous transitions that took place in its neighbourhood.