A density functional and Monte Carlo simulation study of end-grafted polymers immersed by simple fluids is presented. The polymer molecules are modeled as freely jointed tangent hard spheres with the end segments linked to the surface. The authors analyze an influence of the chain length, the grafting density, and a nature of solvent on the brush structure. Adsorption of hard-sphere mixtures on the modified surface is also discussed. The theory precisely approximates simulation data.

A density functional approach to describe adsorption of Lennard-Jones fluids on a surface modified with grafted chains is proposed. The theory is extended to the solute retention in chromatography with chemically bonded phases. The chain molecules are modeled as freely jointed tangent spheres with end segments linked to the surface. The segments interact via Lennard-Jones potential. The effects of grafting density and molecular interactions are discussed. The results are compared with the Monte Carlo simulation data. The theory predicts the most important features of the retention process.

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Monte Carlo simulation in the grand canonical ensemble has been performed to study phase transitions in monolayer films formed by heteronuclear dimers. The phase diagrams have been estimated for some model systems. The results reveal a great variety of vapor–liquid coexistence behaviors depending on the relative strengths of interactions between molecule segments. The structural transitions have been found.

We use coarse-grained molecular dynamics simulations to study the behavior of polymer-tethered particles immersed in fluids of isotropic particles.

We study the impact of selected parameters on the behavior of Janus-like dimers at liquid−liquid interface. The equilibrium orientation and the adsorption depth of a single Janus dimer are calculated using a simple phenomenological method. We have also performed molecular dynamics simulations for different numbers of Janus dimers trapped at the interface between two partially miscible Lennard-Jones fluids. The particles with different wettabilities of both parts of Janus dimers are considered. Depending on the assumed energy parameters, we observe various structures: orientationally ordered monolayers, fractal-like aggregates, compact clusters, and ordered multilayers containing alternately arranged layers built of Janus particles and molecules of the fluids.

A density functional study of adsorption from binary solutions on surfaces modified with tethered chains is presented. The tethered chains are modeled as freely jointed tangent spheres. The fluid molecules are spherical. All species interact via the Lennard-Jones (12-6) potential. The substrate is neutral with respect to all chain segments but the surface-binding segment, and it interacts with the fluid molecules via a Lennard-Jones (9-3) potential. Depending on the parameters of the model, different shapes of the relative excess adsorption isotherms are found. The density profiles of all components are analyzed. It is shown that the surface region is highly inhomogeneous. An influence of the grafting density, the length of grafted chains, the nature of the solution, and its composition on the adsorption mechanism and the structure of the bonded-phase is investigated. The theoretical predictions are consistent with the results of computer simulations and experimental data.

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