Establishment and applications of selective aggregation model of silica sol particles

A study of the aggregation of silica sol particles is presented by using a Monte Carlo simulation including the reaction parameters: activation energy, temperature, and particle concentration. In this simulation, all of the system particles are classified as active and inactive types; only the activated particles can aggregate into clusters, and consequently the aggregation exhibits selectivity. The influences of the above reaction parameters on structural properties and growth kinetics of aggregates are investigated and compared with the existing relevant results. The evolutions of the fractal dimension and size distribution of aggregates over the entire process suggest that the sol system exhibits the behaviors of diffusion-limited cluster aggregation at earlier times and crosses over to those of diffusion-limited aggregation at later times.