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 us ing polystyrene lattices (2a = 180 nm) and alpha-alumina powders with different particle sizes (2a = 1100 nm, 850 nm, and 400 nm), based on heterocoagulation theory. It is apparent that under suitable condition s (medium pH = 3 approximately 4, particle number ratio of latex and a lpha-alumina greater-than-or-equal-to 300/1), the heterocoagulates gen erated from their mixtures were comprised of regular composite particl es. These were made of latex particles adhering on alpha-alumina parti cles in the core. The fraction coverage of lattices increased with dec reasing the particles size of alumina. Further, the behavior was influ enced dramatically by the concentration of alumina particles in the mi xing process; a ragular composite can be generated only from the dilut ed suspensions of ca 0.2 wt%.