Preparation of cross-linked microcapsules entrapping inorganic salt by in-situ polymerization in (W/O/W) emulsion system

Cross-linked microcapsules entrapping ascorbic acid magnesium salt as a cor e material are prepared by in-situ copolymerization of styrene and divinylb enzene in a (W/O/W) emulsion system, The effects of the preparation conditi ons of the microcapsules on the capsule morphologies, the entrapment effici ency and release profiles of the core material are investigated, The entrap ment efficiency of the core material is improved by lowering the volume fra ction of the dispersion phase in the (W/O) emulsion and adding the salt to the outer aqueous phase when tricalcium phosphate is used as the dispersion stabilizer. Both the entrapment efficiency of the core material and the in ternal morphologies of the microcapsules affect the release profiles of the core material.