We present a comparison between results, obtained from different simulation models, for the static properties of end-tethered polymer layers in good solvent. Our analysis includes data from two previous studies--the bond fluctuation model of Wittmer et al. [J. Chem. Phys. 101, 4379 (1994)] and the off-lattice bead-spring model of Grest and Murat [Macromolecules 26, 3108 (1993)]. Additionally, we explore the properties of a similar off-lattice model simulated close to the Theta temperature. We show that the data for the bond fluctuation and the Grest-Murat model can be analyzed in terms of scaling theory because chains are swollen inside the Pincus blob. In the vicinity of the Theta point the structure of the chains is essentially Gaussian in the Pincus blob. Therefore, the data for the second off-lattice model can be compared quantitatively to the self-consistent field theory. Different ways to determine the parameters of the self-consistent field theory are discussed.

A bead‐spring model of a polymer chain with one end attached to a wall is studied by Monte Carlo simulations for chain lengths 16 ≤ N ≤ 256. Two types of adsorption potentials, 9‐3 and 10‐4 Lennard‐Jones (LJ) potentials, between the effective monomers and the wall are assumed. For both cases the adsorption transition where the chain changes its asymptotic statistical properties from a three‐dimensional to a two‐dimensional configuration is located using a scaling analysis. It is shown that the crossover exponent φ = 0.50 ± 0.02 is the same for both LJ potentials. This value is compatible with recent theoretical predictions and simulation results for lattice models with short‐range wall potentials. The results of our study support the expectation that the exponents describing the adsorption transition are universal, i.e., they are not influenced by the precise form and the long‐range character of the adsorption potentials used. The technical aspects of the simulations (which use configurational bias methods as well as histogram re‐weighting) are also carefully discussed.

Articles you may be interested inDensity functional approach to the adsorption of spherical molecules on a surface modified with attached short chains Surface phase transitions in athermal mixtures of hard rods and excluded volume polymers investigated using a density functional approachThe Soret effect in dilute polymer solutions: Influence of chain length, chain stiffness, and solvent quality R gʈ ϰN 2 , N→ϱ, 2 ϭ3/4, TϽT a , ͑3͒while R gЌ stays finite in this limit. 7-12 The asymptotic exponents and scaling properties of this adsorption transition have been clarified 10,11,13 by mapping the problem to the equivalent problem of the critical behavior of a semi-infinite magnet with an exchange interaction J s at the surface, different from the exchange interaction J in the bulk. 14 For this problem, the Ginzburg-Landau-Wilson Hamiltonian is ͓x ϭ( ʈ ,z), ʈ being a coordinate parallel to the wall͔ a͒ Electronic

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