Microthermogravimetry of a single microcapsule using silicon microresonators.
Microthermogravimetry of a single microcapsule using silicon microresonators.
复制标题
使用硅微谐振器对单个微胶囊进行显微热重分析。
作者：
Dongkyu Lee;Y. Park;S. Cho;Myungsun Yoo;Namchul Jung;Minhyuk Yun;Wooree Ko;S. Jeon
将含氯苯的聚氨酯微胶囊置于硅悬臂梁的自由端，测量了共振频率的温度依赖性。当悬臂被加热时，共振频率在109和270摄氏度处显示出阶跃式增加，这分别是由于胶囊的破裂和聚氨酯壳的热降解。由于由悬臂测量的单个胶囊的破裂的频率变化比由常规热重分析（TGA）测量的转变尖锐得多，所述常规热重分析测量以大尺寸分布为特征的胶囊集合的平均质量变化。当两个胶囊被放置在悬臂梁上时，它们各自的破裂温度可以被清楚地识别。此外，聚氨酯壳的渗透性，相对于氯苯，进行了测量，并观察到破裂温度随着渗透性的增加而降低。
A chlorobenzene-containing polyurethane microcapsule was placed on the free end of a silicon cantilever, and the temperature dependence of the resonance frequency was measured. As the cantilever was heated, the resonance frequency showed steplike increases at 109 and 270 degrees C that were due to the rupture of the capsule and the thermal degradation of the polyurethane shell, respectively. The frequency changes due to the rupture of a single capsule measured by the cantilever were much sharper than the transitions measured by conventional thermogravimetric analysis (TGA), which measures the average mass change of a collection of capsules characterized by a large size distribution. When two capsules were placed on the cantilever, their individual rupture temperatures could be clearly identified. In addition, the permeability of the polyurethane shell, with respect to chlorobenzene, was measured, and the rupture temperature was observed to decrease with increasing permeability.