Am. Freitas et Mm. Sharma, Effect of surface hydrophobicity on the hydrodynamic detachment of particles from surfaces, LANGMUIR, 15(7), 1999, pp. 2466-2476
Experiments were performed to evaluate the hydrodynamic force required to d
etach colloidal particles from substrates by fluids in simple shear flow, T
he role of DLVO and acid-base interactions on the process of adhesion and r
emoval of colloidal particles, from model surfaces, in various fluid enviro
nments was investigated. Particles and substrates with varying degrees of h
ydrophobicity were used. The free energy of interaction between these surfa
ces in a number of fluid media was calculated using the acid-base approach.
Good qualitative agreement was obtained between calculated values of free
energy of interaction using the acid-base approach and the critical hydrody
namic force required to detach the particles if long range electrostatic re
pulsion is properly accounted for. Results for a range of particles and sub
strates of varying hydrophobicity and for a range of solvents can be consis
tently explained using this approach.