Preparation of Double-Layer Microcapsules Coated by a Synthesized Lipid and Their Controlled Release.

A double layer microcapsule composed of nylon and polystyrene has been prepared by a combined process of interfacial polymerization and solvent evaporation. The release rate of sodium ions as a core material was investigated with the microcapsules coated by a synthesized lipid. The permeation rate drastically changed corresponding to the phase transition temperature of the bilayer membranes composed of the lipid. The permeability of the core material above the phase transition temperature was 1-order of magnitude higher than that below the temperature. A functional microcapsule in which a core material is controlled by a membrane structure can be prepared by coating the microcapsule with a synthesized lipid.