Mechanics of physisorption on elastomer surface

Mechanical aspects of physisorption on elastomeric substrates are studied via a continuum model in combination with the Lennard-Jones potential. In light of the incompressibility of elastomers, it is shown that the presence of a zero-dimensional adsorbate gives rise to a distributed force on the surface of the substrate. The induced surface deformation is determined, and the adsorption force and energy which depend on the substrate stiffness are derived. The results are then used to examine mutual interaction between two like adsorbates with small spacing, showing complicated attraction and repulsion arising from elastic deformation of the substrate. The dipole and quadruple moments of an adsorbate are also calculated, and the multipole approximation is adopted to quantify the interaction when the two adsorbates are separated remotely.