碳酸钙中空微球的制备及机理

采用沉淀反应方法，利用聚乙烯吡咯烷酮(PVP)和十二烷基磺酸钠(SDS)复合添加剂作为有机模板，制备了中空球状方解石型碳酸钙，同时考察了不同温度、SDS和PVP浓度对碳酸钙结晶和聚集行为的影响，进而对其反应机理进行了初步探讨。

Preparation and mechanism of CaCO3 hollow microspheres

The CaCO3 hollow microspheres were synthesized by the facile precipitation reaction of aqueous solutions CaCl2 and Na2CO3 in the presence of polyvinylpyrrolidone(PVP)and sodium dodecyl sulfonate(SDS).The aim of introducing the surfactant/polymer complex into the reaction system was to not only understand the effects of the surfactant/polymer complex on the crystallization and aggregation of calcium carbonate,but also explore a realizable and simple preparation method.The concentration of SDS was an important factor for controlling the synthesis of hollow CaCO3 microspheres.The PVP-SDS complex micelles played a key role in controlling the growth of biominerals.The products were characterized with field emission scanning electron microscope(FESEM),transmission electron microscopy(TEM)and X-ray diffraction(XRD).The effect of experiment conditions on the crystallization and aggregation of calcium carbonate was investigated.The results showed that the hollow microspheres were obtained under the conditions of concentration of SDS 10 mmol·L-1,dosage of PVP 1.0% and temperature 20℃.The reaction mechanism was discussed.