SiO_2/十八烷酸相变微胶囊的制备与表征

Preparation and characterization of SiO_2/stearic acid microencapsulated phase change materials

以水玻璃和十八烷酸为基本原料，利用两者反应生成表面活性剂十八烷酸钠来促进十八烷酸在水中的分散与形成胶束，并使由水玻璃提供的硅氧四面体[SiO4]完成对胶束的包裹，然后再通过调整pH值，使十八烷酸钠还原为具有相变性能的十八烷酸，通过上述方法制得的以[SiO4]结构为囊壁、十八烷酸为囊芯的相变微胶囊。SEM、DSC、XRD、FTIR等对其表面形貌、热性能、囊壁和囊芯结构的表征结果表明，其粒度均匀，为在0．40～0．6μm，表面光滑，相变焓为78．2J／g。该方法较好的解决了相变微胶囊制备过程相变材料的分散问题，既使辅助材料的品种简化，又提高了微胶囊中相变材料的有效含量。

The preparation of a new kind of SiO2/ stearic acid microencapsulated phase change materials（microPCMs） which used sodium silicate and stearic acid as the basic raw materials was described in this paper. The progress of microPCMs which [SiO4 ] to the wall for stearic acid batteries can be divided into two steps. The first stearic dispersed method is through the reaction of surfactant between the water glass with stearic acid, the formation of MicroPCMs will be reached after the completion of pH value by adjusting the water glass to provide [SiO4],at the same time stearic acid reduced from stearic acid sodium salt. Based on this, some testing technology such as SEM of the surface, DSC of the thermal properties, XRD of core structure and FTIR of wall structure is used of micro-capsules evaluation, the result shows that the size of the micro-capsules has a particle size at 0. 40-0. 6μm, and a uniform, smooth surface, with a phase change enthalpy for 78.2J/g. The method get a better way to solve the organic phase change materials in the process of decentralization of the problem, not only reduced the preparation of the necessary materials types of raw materials, but also improved the effective content of phase change materials increased