Manufacture of microcapsules consisting of porus polymer as inside wall and ultra-thin membrane as outside wall material

点击翻译按钮获取中文摘要

A technique of microcapsule manufacturing by in situ polymerization was developed in this research. Two kinds of microcapsules were prepared, one containing organic solvent as core material and the other containing aqueous solution as core material, as described separately below.1. Microcapsules containing organic liquid as core material Microcapsules of 50 - 400 m in average size consisting of isooctane as core material and cross-linked polystyrene as wall material were prepared by using in situ polymerization. That is, organic phase of isooctane, styrene and divinyl benzene containing polymerization initiator was dispersed in aqueous solution containing a prescribed amount of a dispersion agent (arabic gum), and a porous polystyrene microcapsule was prepared by in situ polymerization. The effects of operating conditions on particle size, wall thickness and permeability coefficient were investigated to obtain the following results. (1) Monomer concentration and rotational speed of sti … More rrer were main operating factors in controlling the wall thickness of microcapsule. (2) The permeability characteristics were different between the unit-core and multi-core microcapsules.2. Microcapsules containing aqueous solution as core material Microcapsules of 20 - 250 m in average size consisting of aqueous solution as core material and cross-linked polystyrene as wall material were prepared. That is, W/O/W emulsion from water, styrene, divinyl benzene and so on was prepared, and in situ polymerization was completed in the dispersed oil phase to obtain the microcapsules. the effect of operating conditions on the physical properties of the microcapsules was discussed. The following results were obtained. (1) Multi-core microcapsules were obtained from this procedure. (2) The average size of microcapsules depends on the rotational speeds, interface active agent (DBSNa) concentrations, PVA concentrations and dispersion volume fractions. (3) Notable permeability of Ni^<2+> from the inside of microcapsules for first 30 minutes and negligible small permeability after that time were detected. Less