聚脲体系辣素微胶囊的界面聚合法制备与热降解动力学

在乳液体系中,以聚脲为壁材,以界面聚合法制备了包裹辣素同系物--N-香草基壬酰胺的微胶囊.通过正交实验确定了获得较好包埋率的反应条件:反应温度50℃、乳化值8、乳化转速2000 r/min.红外光谱对照显示囊心与形成壁材的单体间存在键合;吸附等温曲线为标准Ⅰ类曲线,并由此假设微胶囊为紧密堆积形式,以单个扫描速率升温法进行了微胶囊的热降解实验,采用Freeman-Caroll方法与Achar-Brindley-Sharp-Wendworth方法进行了热重数据的处理,求得了动力学参数,回归系数显示这2种处理方法所获得的反应级数一致.

Interfacial Polymerization Preparation and Thermal Decomposition Kinetics of Polyurea Microencapsules Containing Capsaicine

Polyurea microencapsules containing N-pelargonylvanillylamide, the homolog ot capsaicine, were prepared in emulsion by interfacial polymerization methods. By using orthogonal experiments, the optimum temperature, value of HLB and emulsification speed were determined. The results of IR contrast showed that chemical bonds existed between capsule core and monomer forming capsule wall. TEe absorption curve was regarded as standard I, and depending on it, the microencapsules were considered to be in form of cumulating tightly. So the data of TGA which were obtained by single scanning rate method were analyzed by Freeman-Caroll method and Achar-Brindley-Sharp-Wendworth method. The kinetics parameters were determined. The coefficient of regression R demonstrated that the reaction order that was deduced by two methods was same.