Adsorption of colloid particles at partially covered surfaces

The adsorption kinetics of negatively charged polystyrene latex at mica surface precovered with smaller sized (submicrometer) latex particles was investigated experimentally. The direct microscope observation method combined with the impinging jet technique was used in this study. Experimental results were presented concerning the initial flux and adsorption kinetics of larger particles at surfaces partially covered with smaller sized latex particles. The experimental results were interpreted in terms of the Monte Carlo simulations performed using the random sequential adsorption (RSA) model. Limiting analytical solutions for predicting the initial flux and adsorption kinetics were also formulated. It was found that the experimental results were in good agreement with theoretical predictions( derived for hard particle interaction potential). This confirmed the hypothesis that small colloid particles present in low concentration at surfaces considerably diminish adsorption rates of larger particles. (C) 1997 Academic Press.