微乳液条件下碳纳米管微胶囊相变溶液的优化合成

The Opitimized Synthesis of Phase Change Solution of Carbon Nanotubes Microcapsule under Microemulsion Condition

采用原位聚合法合成一种以棕榈酸为芯材,蜜胺树脂为壁材,Pickering乳液为稳定剂的相变微胶囊.再将相变微胶囊和预处理碳纳米管一同混入Pickering乳液中,得到复合相变溶液.通过扫描电镜、红外光谱表征预处理前后碳纳米管和相变微胶囊的表面形貌,并讨论了碳纳米管的掺入对复合相变溶液的热力学及表面张力等性能的影响.结果表明:预处理后碳纳米管的缠绕性明显改善,管壁出现较多羟基、羧基官能团,反应活性提高;合成的相变微胶囊表面相对光滑,粒度均匀;掺入1%预处理碳纳米管可使复合相变溶液的导热率提高50%以上,基本消除溶液的过冷现象.

A phase change microcapsule with palmitic acid as core and melamine resin as shell,Pickering emulsion as stabilizer was synthesized by in-situ polymerization.Then the phase change microcapsules and the modified carbon nanotubes（CNTs）were mixed into the Pickering emulsion to obtain the composite phase change solution.The surface morphology of carbon nanotubes（CNTs）and phase change microcapsules（PCMs）before and after pretreatment were characterized by fourier transform infrared spectroscopy（FT-IR）and scanning electronic microscopy（SEM）respectively.The influences of amount of CNTs on the thermodynamic properties and surface tension of composite phase change solution were investigated.The results show that after pretreatment,the winding property of CNTs is obviously improved,there are more hydroxyl groups and carboxyl functional groups on the wall,the reaction activity is improved,the surface of the synthesized phase change microcapsules is relatively smooth and the particle size of CNTs are more uniform.When CNTs addition reaches 1%can greatly improve the thermal conductivity of the phase change solution by more than 50 percent,and the super-cooling phenomenon of solution can be basically eliminated.