Novel preparation method of microencapsules was
developed on the basis of the liquid coalescence method followed by phase
separation.Oil droplets of limonene dissolving expanded polystyrene as a shell
material were forced to collide and coalesce with the Isopar oil droplets of
core material in the continuous wates phase. When two kinds of oil droplets are
collided and coalesced with each other, expanded polystyrene dissolved in the
limonene oil may be phase-separated in the oil droplets newly formed to form
the microcapsule shell, because the Isopar oil was a poor solvent for expanded
polystyrene but a good solvent for the limonene oil.In the experiment,
the diameter (or number) of limonene oil droplets dissolving expanded
polystyrene was mainly changed, because the coalescence frequency between the
droplets is strongly dependent on the number of droplets.Favorable
core shell types of microcapsules with the shell thickness from 1.0 to 5.0μm were
able to be prepared under all the experimental conditions adopted here.
Cite this paper
Y. Yokoyama, K. Fuchigami, Y. Taguchi and M. Tanaka, "Preparation of Microcapsules with Liquid Droplet Coalescence Method Followed by Phase Separation," Journal of Encapsulation and Adsorption Sciences, Vol. 3 No. 3, 2013, pp. 93-97. doi: 10.4236/jeas.2013.33011.
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