The influence of nanoparticles on polystyrene adhesion

The effect of silica nanoparticles on the adhesion of micron-sized polystyrene particles to a mica substrate has been investigated using a centrifuge to both ‘spin-on’ and ‘spin-off’ the polystyrene particles under different centrifuge conditions. In the absence of nanoparticles, the quantity of polystyrene particles removed increased steadily as the spin-off force was increased. The particle roughness and the number of particle–particle contacts were described as being responsible for this gradual removal.When nanoparticles were added, an increase in the overall removal of polystyrene particles under a given centrifugal force was seen, when compared to the water-only data. The greatest effect was observed for the lowest nanoparticle concentrations used. These results suggest that the interactions between nanoparticles and surfaces are complex and need to be studied in greater detail to thoroughly understand the particle detachment process.