Adhesion interaction in water/n-alcohol mixtures between silanized silica and polymer particles

The adhesion of polyethylene and nylon particles to silanized silica plates was investigated in water/n-alcohol (methanol, ethanol, I-propanol, and l- butanol) mixtures. Silica plates were treated with gamma-aminopropyltrietho xysilane, methyltriethoxysilane, and perfluoroethyltrimethoxysilane. The nu mber of particles adhering to the plate at 60 min as an apparent equilibriu m adhesion value increased as a result of the silanization of silica and de creased with increasing volume ratio of n-alcohol in the water/n-alcohol mi xtures. The acid-base components of the surface free energies of the substr ates and liquids were decreased by the silanization of silica and by the ad dition of ethanol to water. The apparent equilibrium particle adhesion is d iscussed in terms of the total potential energies of interaction which were calculated as the sum of the electrical double layer, Lifshitz-van der Waa ls, and acid-base interactions, using the electrokinetic potentials and the surface free energy components. In addition, the relationship between the extent of particle adhesion and the work of adhesion was investigated. The particle adhesion in the present systems was found to be dominated by the a cid-base interaction between the particle and the substrate.