Preparation of Composite Fine Particles from Polymer Lattices and Inorganic Powder

Suitable Conditions to prepare regular composite fine particles which were comprised of organic and inorganic compounds were investigated using polystyrene lattices (2a=180nm) and a-alumina powders with different particle sizes (2a=1100nm, 850nm, and 400nm), based on heterocoagulation theory. It is apparent that under suitable conditions (medium pH=3-4, particle number ratio of latex and a-alumina≥ 300/1), the heterocoagulates generated from their mixtures were comprised of regular composite particles. These were made of latex particles adhering on a-alumina particles in the core. The fraction coverage of lattices increased with decreasing the particles size of alumina. Further, the behavior was influenced dramatically by the concentration of alumina particles in the mixing process; a ragular composite can be generated only from the diluted suspensions of ca. 0.2 wt%.