负载相变微胶囊的三聚氰胺/二氧化硅柔性气凝胶

Structure and Properties of Melamine/Silicon Dioxide Flexible Aerogels Loaded with Phase Transition Microcapsules

为进一步拓展气凝胶材料的功能性应用,使其在建筑隔热及节能领域有更为广泛的应用,以三聚氰胺海绵(MF)作为骨架支撑,通过真空吸附颗粒改性的相变微胶囊(MEPCM),并通过原位溶胶法原位生长硅基气凝胶,制得负载相变微胶囊的三聚氰胺/二氧化硅柔性气凝胶(PMS)。研究了相变微胶囊负载量及凝胶温度对复合材料结构及性能的影响。通过扫描电子显微镜结果分析可知,相变微胶囊吸附于MF骨架内部,气凝胶颗粒在微胶囊及表面生长,比表面积在159~608 m^(2)/g变化,具有1~5 nm和10~50 nm多级孔径。通过差示扫描量热分析可知,PMS的相变温度与建筑保温隔热相适应,相变焓可达到75.1 J/g,经过多次循环后热焓值损失极小。复合材料形成稳固的宏观结构,力学性能明显提升,为其在建筑热控领域应用提供支持。

In order to further expand the functional application of aerogel materials and make them more widely used in building thermal insulation and energy saving,phase change microcapsules(MEPCM)modified with vacuum adsorption particles were prepared using melamine sponge(MF)as skeleton support,melamine/silicon dioxide flexible aerogels(PMS)loaded with phase change microcapsules were prepared by in situ growth of silica-based aerogels through sol-gel method.The effects of the phase change microcapsule loading and gel temperature on the structure and properties of the composites were studied.The results of scanning electron microscope analysis show the the phase change microcapsules are adsorbed inside the MF skeleton,the aerogel particles grow on the microcapsule and its surface,the specific surface area varies from 608 m^(2)/g to 159 m^(2)/g,and the pore diameters are 1~5 nm and 10~50 nm.The differential scanning calorimetry(DSC)shows that the phase change temperature of PMS is suitable for building thermal insulation,the enthalpy of phase change can reach 75.1 J/g,and the enthalpy loss is very small after several cycles.The composite material forms a stable macrostructure and its mechanical properties are improved obviously,which lays a foundation for its application in the field of building thermal control.