正十八烷相变纳胶囊/多壁碳纳米管流体的制备及性能表征

Preparation and characterization of n-octadecane phase-change nano-capsule/MWCNTs fluid

采用原位聚合法合成了一种以正十八烷为芯材,密胺树脂为壁材的相变纳米级胶囊;通过超声搅拌将相变纳胶囊和功能化的多壁碳纳米管复合,得到一种稳定的复合相变流体,并通过红外光谱(FT-IR)、扫描电镜(SEM)、Zeta电位和差示量热(DSC)等手段对其进行表征。结果表明:Fenton试剂处理过的多壁碳纳米管表面带有大量的—OH和—COOH等亲水性基团;合成的正十八烷相变纳胶囊为直径200~400nm的表面光滑的圆球形;Zeta电位测试结果显示,当表面活性剂曲拉通X-100和十六烷基三甲基溴化铵(CTAB)的用量都为3.3%时,复合相变流体的分散稳定性最好;DSC结果显示,复合相变流体使用前、后烘干物的熔融焓和结晶焓都在110J/g左右。

A phase change nano-capsule with n-octadecane as core material and melamine resin as wall material was synthesized by in-situ polymerization.Then,the phase-change nano-capsule and the multi-walled nanotubes(MWCNTS)functionalized were stirred together by ultrasonic method to obtain a stable composite phase-change fluid which was characterized through FT-IR,SEM,Zeta potential and DSC.The results shown that MWCNTStreated by Fenton reagent had some hydrophilic groups such as a large amount of—OH and—COOH on the surface.The noctadecane phase-chage nano-capluse formed smooth sphere whose diameter were between 200~400 nm.Zata potential test results illustrated that when the amount of surfactant Triton X-1000 and CTAB were both 3.3%,the composite phase-change fluid had the optimal dispersion stability.In addition,through the DSC results,the melting enthalpy and crystallization enthalpy of the dried composite phase-change fluid were both keeping 110 J/g during the using period.