本文详细阐述了近年来有机烷烃相变材料(PCMs)及其微胶囊化的研究进展和应用前景.单一组分的有机烷烃PCMs一般均具有理想的相变性质,但由于相变点固定使其应用受到限制,为了满足实际需要,通过不同组分的复配,可以实现对相变温度范围的调节.单一组分直链烷烃PCMs的价格往往很高,石蜡由于含有不同碳原子数的有机烷烃而常被用作PCMs.另一方面,由于有机烷烃PCMs发生固-液相变时,通常会伴有体积膨胀等问题而带来不便.微胶囊化可以将PCMs转化为固体粉末,并通过增加比表面积来提高传热效率,在传热、储能和控温等方面具有广泛的应用价值.本文重点介绍了PCMs微胶囊化的三种化学方法,即原位聚合、界面聚合和悬浮聚合,并与喷雾干燥、相分离和溶胶.凝胶等方法进行了比较.%In this paper,research progresses of organic alkane phase change materials(PCMs) and potential applications of their microencapsulation are introduced systematically. The pure alkane has ideal phase change properties, but its fixed phase change point limits its applications. Practical needs are usually met by mixing different components of alkanes for adjusting their phase change properties. Generally speaking, homogeneous mixing is required to obtain a narrow temperature range of phase transition without phase separation. Because of the high cost of pure alkanes, applied researches were focused on paraffin systems. On the other hand, most of organic alkane PCMs undergo solid-liquid phase change, which can lead to inconvenience by swelling. Microencapsulation is an effective way to solve the problem of liquid PCMs. By means of chemical methods, such as in situ polymerization,interface polymerization and suspension polymerization, liquid PCMs can be enwrapped into microcapsules and turned into solid powders. Additionally, spray drying, phase separation and sol-gel methods are also available to encapsulate PCMs. The microencapsulation of organic alkanes PCMs can also solve the poor heat transfer problem by increasing thermal conductivity and specific surface area of PCMs. Microencapsulated PCMs has a wide range of great potential applications in heat transfer,energy storage and temperature control.
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