MUF/十八烷相变微胶囊的制备与性能研究

Synthesis and property of MUF/octadecane PCM

以三聚氰胺-尿素-甲醛树脂(MUF)为壁材,十八烷为芯材,采用原位聚合法制备出了表面光滑、分散均匀的相变微胶囊。通过扫描电镜(SEM)、差示扫描量热仪(DSC)、红外光谱(FT-IR)和偏光显微镜等方法分别测试了微胶囊的表面形貌、相变性能、化学结构和粒径分布;并采用偏光显微镜研究了微胶囊相变过程中的形貌变化。结果表明:乳化剂(SDS)用量和固化pH对微胶囊形貌有很大的影响,当SDS浓度为4%,pH为5.5~6时,制备的微胶囊表面光滑、分散均匀,平均粒径为12.2μm;DSC测试结果表明微胶囊熔融焓(ΔH_m)为223.5J/g、结晶焓(ΔH_c)为223.0J/g,芯材含量为95%,微胶囊的相变温度与芯材基本相同。

The phase change microcapsules(PCM)containing n-octadecane with a melamine-urea-formaldehyde copolymer shell were successfully synthesized by in-situ polymerization.The surface morphology,melting and crystallization properties,chemical structure and diameter distribution of the microcapsules were investigated by using SEM,DSC,FT-IR and polarizing microscope respectively.And the morphology changes of the microcapsules during phase transition were observed by polarizing microscope.The results showed that emulsifier concentration and pH value had a great influence on the morphology of the microcapsules.The optimal emulsifier concentration and pH value were 4%and 5.5~6respectively.The microcapsules prepared at this condition were dispersed uniformly and had smooth surface with average partical size of 12.2μm.The DSC testing results showed that the microcapsules had the melting enthalpy of 223.5J/g,the crystalline enthalpy of 223.0J/g and core content of 95%.The phase transition temperature of microcapsules was the same as that of core material.