磁性显示微胶囊的同轴双喷头法制备

利用微胶囊技术,以海藻酸钠和明胶为壁材,四氧化三铁的混合溶液为芯材,采用同轴双喷头法制备了磁性显示微胶囊。考察了芯材溶液压强、壁材溶液压强、芯材溶液搅拌速度、喷头高度和喷头角度对微胶囊合格率的影响。结果表明,最佳制备参数为芯材压强175 kPa,壁材压强300 kPa,芯材溶液搅拌速度600 r/min,喷头高度40 cm,喷头角度35°。在最佳条件下制备出的磁性显示微胶囊粒径主要分布在100～250μm,内外表面光滑,囊壁透明,分散性好,形态完整,具有良好磁响应性。

Preparation of magnetic showing microcapsules by the concentric double nozzle method

Magnetic showing microencapsulations were prepared by the microencapsulation technology with the concentric double nozzle method,using sodium alginate and gelatin as wall materials and mixed solution of Fe3O4as core materials.The influences of pressure of the core material,pressure of the wall material,stirring speed of core material solution,vertical height of nozzle,and horizontal angle of nozzle on the yield of microencapsulations were investigated.The results show that the optimum reaction conditions are as follows: pressure of core material 175 kPa,pressure of wall material 300 kPa,stirring speed of core material solution 600 r/min,vertical height of nozzle 40 cm,and horizontal angle of nozzle 35°.The magnetic showing microencapsulations prepared with the optimum conditions possess many merits,such as smooth inner and outer surface,transparence,good dispersity,complete morphology,good magnetic showing,and the particl size of this microencapsulations is 100–250 μm.