多壁碳纳米管/硬脂酸-十八醇@脲醛树脂微胶囊的制备及表征

Preparation and characterization of MWCNTs/stearic acid-octadecyl alcohol@urea formaldehyde resin phase change microencapsules

通过原位聚合法以硬脂酸-十八醇低共融复合相变材料(SA-OA,质量比为50.02%,相变温度为55℃)为芯材,三聚氰胺改性的脲醛树脂(UF)为壁材,氨基化多壁碳纳米管(MWCNTs-NH2)为高导热填料制备了MWCNTs/SA-OA@UF相变微胶囊。采用FTIR、SEM、DSC、TGA和导热系数仪,对MWCNTs/SA-OA@UF相变微胶囊的化学结构、表面形貌、相变性能和导热性能进行表征。讨论了不同的MWCNTs修饰方法、不同乳化剂种类和MWCNTs-NH2添加量对SA-OA@UF相变微胶囊的影响。结果表明:MWCNTs-NH2在溶液中分散性良好;十二烷基苯磺酸钠(SDBS)和曲拉通X-100复配乳化剂使SA-OA@UF相变微胶囊的表面形貌更加光滑平整;添加质量比为0.5%的MWCNTs-NH2,使MWCNTs/SA-OA@UF相变微胶囊的导热系数达到0.224W/(m·K),提高了38%(55℃),包覆率提高了6.9%,粒度更加均一,热稳定性有明显提高。

The multi-walled carbon nanotubes/stearic acid-octadecyl alcohol@urea formaldehyde resin(MWCNTs/SA-OA@UF)phase change microcapsules with SA-OA eutectic composite phase change materials(at the mass ratio of 50.02%,phase change temperature was 55℃)as core material,UF modified by melamine as wall material and amino multi-walled carbon nanotubes(MWCNTs-NH2)as highly thermally conductive filler were prepared by using in-situ polymerization method.The chemical structure,morphology,thermal properties and thermal conductivity of the MWCNTs/SA-OA@UF phase change microcapsules were characterized by FTIR,SEM,DSC,TGA and thermal conductivity meter.The effects of different MWCNT modification methods,different types of emulsifiers and the amount of MWCNTs-NH2 added in the SA-OA@UF phase change microcapsules were discussed.The results show that the MWCNTs-NH2 have good dispersibility in the solution;The compounded emulsifiers of sodium dodecyl benzene sulfonate(SDBS)and Triton X-100 make the surface morphology of the SA-OA@UF phase change microcapsules smoother and smoother;The addition of MWCNTs-NH2 with the mass ratio of 0.5% make the MWCNTs/SA-OA@UF phase change microcapsule’s thermal conductivity reaches 0.224 W/(m·K),which increases by38%(55℃),the coating rate increases by 6.9%,the particle size is more uniform and the thermal stability is significantly improved.