分别采用化学键联和物理共混的改性方法制备了两种相变材料 ,并用偏光显微镜和透射电镜分别对它们进行观察 ,讨论两者的微相结构差异和结构随温度的变化 ,同时研究了微相结构与储热性能的关系。结果表明 :采用化学键联法制得的相变材料具有更小、更稳定的微相区 ,并且是通过固—固相变来储能和释能的 ;而采用物理共混法制得的相变材料 ,仅仅是两种原料聚乙二醇和二醋酸纤维素的简单混合 ,实际上发生的仍为固—液相变 Two kinds of phase change materials were prepared by chemical bonding and physical blending respectively. They were observed respectively by polarization microscope and transmission electron microscope. The difference of microstructure and the change of structure with temperature were discussed. Relationship between micro-phase structure and heat storage performance. The results show that the phase-change materials prepared by chemical bonding have smaller and more stable micro-phase regions, and they are stored and released by solid-solid phase transformation. However, the phase change materials prepared by physical blending method , Just a simple mixture of two raw materials, polyethylene glycol and cellulose diacetate, actually occurs as a solid-liquid phase change