基于相反转法纳胶囊相变材料的制备与表征

Preparation and Characterization of Nanocapsulated Phase Change Materials Based on the Method of Phase Inversion

将低能乳化法应用到纳胶囊的制备过程中,以山梨糖醇酐油酸酯(Span80)与失水山梨醇单油酸酯聚氧乙烯醚(Tween80)为复合乳化剂,成功合成了以正十八烷为芯材,脲醛树脂为壁材的相变材料纳胶囊。采用扫描电子显微镜、Zeta电势、差示扫描量热分析和热重等表征手段对纳米乳液和纳胶囊的性能进行了表征分析,研究结果表明,随着乳化剂含量的增加,乳液的粒径变小且分布变窄,同时稳定性增加;制备的纳胶囊平均粒径在500 nm左右,表面相对光滑;随着壁材单体含量的减少,纳胶囊的热函值减小,被包覆的囊芯含量下降。

Phase change material nano-capsules containing n-octadecane were synthesized using urea-formaldehyde shell with sorbitan monooleate （Span80） and polyoxyethylene （20） sorbitan monooleate （Tween80） as emulsifiers based on the low-energy emulsification methods. The properties of the prepared nano-emulsion and nano-capsules were characterized by such as SEM, zeta potential, differential scanning calorimetry analysis and thermogravimetric analysis. The results show that with increase of the surfactant concentration, the droplet size becomes smaller and the distribution becomes narrow, the stability of the nano-emulsion increases at the same time. The average diameter of the prepared nano-capsules is about 500 nm and the surface is relatively smooth. The enthalpy of nano-capsules decreases and the encapsulation rate is lower as the mass ratio of monomer/core decreases.