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Direct finite element calculations are carried out to study the relationship between the platelet orientational distribution and the overall effective barrier properties (gas permeability) of mineral filled composites. We consider multi-inclusion computer models with microstructures representative of the dilute, semi-dilute and concentration regimes. In the dilute regime, our numerical predictions validate the results of multiple scattering expansion theory. For the semi-dilute and concentration regimes representative of most real composites, we present numerical estimates quantifying the difference between the barrier properties of composites with fully aligned and randomly oriented platelets. Our numerical results can also be used to quantify the effect of the geometric factor on the gas barrier properties of polymer–mineral hybrid nanocomposites.

Modification of surfaces with self‐assembled mono‐layers (SAMs) represents a powerful and innovative tool for adjusting physical and chemical properties of surfaces. The adsorption of isomeric molecules with relatively strong and oppositely oriented molecular dipoles, 1,2‐(HS)2‐1,2‐C2B10H10 and 9,12‐(HS)2‐1,2‐C2B10H10, on a flat silver surface is investigated in order to adjust its work function in a desired way. Time‐of‐flight secondary ion mass spectroscopy (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS) are used to prove that both isomers (i) chemisorb on a silver surface as thiolates and (ii) exhibit comparable surface densities. Densely packed surfaces of both SAMs are additionally investigated by electrochemical impedance spectroscopy, and effective surface passivation is observed. Co‐deposition of both derivatives is shown to enable effective and fine adjustment of the surface work function value within a range of ∼1 V, which is confirmed by Kelvin probe force microscopy (KPFM). Experimental data indicate faster SAM formation for the former isomer. Contribution of the interface Ag–S bonds to the work function changes is quantified.