Polymethyl methacrylate based phase change microencapsulation for solar energy storage with silicon nitride
Polymethyl methacrylate based phase change microencapsulation for solar energy storage with silicon nitride
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DOI：
10.1016/j.solener.2015.02.036
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发表时间：
2015-05
期刊：
影响因子：
6.7
通讯作者：
Yanyang Yang;X. Ye;Jie Luo;G. Song;Liu Yuan;G. Tang
中科院分区：
文献类型：
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作者：
Yanyang Yang;X. Ye;Jie Luo;G. Song;Liu Yuan;G. Tang
为了提高聚甲基丙烯酸甲酯（PMMA）为壳、正十八烷为芯的相变微胶囊（PCM）的热性能和力学性能，采用氮化硅作为相变微胶囊的填料。通过构建“分子桥”对氮化硅表面进行改性，消除了无机氮化硅颗粒与有机PMMA壳层之间的界面层。因此，成功地制备了以聚甲基丙烯酸甲酯为壳、正十八烷为芯的改性氮化硅相变微胶囊。采用傅里叶变换红外光谱（FTIR）、场发射扫描电镜（FESEM）、差示扫描量热仪（DSC）和热重分析仪（TGA）对微胶囊进行了表征。采用微/纳米硬度计对壳体的力学性能进行了测试。结果表明，当改性氮化硅质量分数为10%时，正十八烷含量为66.4%的MPCM的熔化潜热为121.11 J/g，结晶潜热为122.01 J/g。改性后的氮化硅不仅提高了材料的热性能，而且还提高了材料的机械强度，最高可达16.24 mN，是PCM的4倍。此外，MPCM表面的褶皱提高了比表面积，并适应相变过程中的体积变化。所制备的MPCM有望在太阳能储能技术中表现出更好的性能。
Silicon nitride was applied to enhance the thermal performance and mechanical properties of phase change microencapsulation (PCM) based on polymethyl methacrylate (PMMA) shell and n-octadecane core. ‘A molecular bridge’ was constructed to modify the surface of silicon nitride and to eliminate boundary layer between inorganic silicon nitride particle and organic PMMA shell. Thus, an innovative modified silicon nitride phase change microencapsulation (MPCM) with which silicon nitride uniformly disperses in PMMA as shell and n-octadecane as core was successfully prepared. The microencapsulation was characterized using Fourier transformed infrared spectrophotometer (FTIR), field emission scanning electron microscope (FESEM), differential scanning calorimeter (DSC) and thermal gravimetric analyzer (TGA). A micro/nano-hardness tester was also employed, in order to investigate mechanical performance of shell. The result shows that the MPCM containing 66.4% n-octadecane has 121.11 J/g latent heats of melting and 122.01 J/g latent heats of crystallization with the modified silicon nitride percentage up to 10 wt.%. The modified silicon nitride could not only enhance thermal performance, but also improve mechanical strength up to 16.24 mN which is 4 times higher than that of PCM. Additionally, wrinkles on the surface of MPCM improved special surface area as well as adaptation of volume changes during phase change process. The prepared MPCM is expected to exhibit better performance in solar energy storage technology.