石蜡/膨胀石墨复合相变储热材料的性能研究

Study on performance of paraffin/expanded graphite composite phase-change material

以石蜡为相变材料、膨胀石墨为支撑结构,利用膨胀石墨的多孔吸附特性,制备出了石蜡含量90%(质量分数)的石蜡/膨胀石墨复合相变储热材料。采用扫描电镜(SEM)、偏光显微镜(PM)、X射线衍射(XRD)及差示扫描量热分析(DSC)对复合相变储热材料的结构和性能进行了表征。结果表明,膨胀石墨吸附石蜡后仍然保持了原来疏松多孔的蠕虫状形态,石蜡被膨胀石墨微孔所吸附,在石蜡质量含量为90%时仍保持定型特性;复合相变储热材料没有形成新物质,其相变温度与石蜡相似,相变焓与基于复合材料中石蜡含量的相变焓计算值相当。

Composite paraffin/expanded graphite phase-change material （PCM） containing 90% （mass fraction） of paraffin were prepared by using paraffin as a latent heat-storage material and expanded graphite as a supporting matrix. The structure and thermal properties of PCM were then characterized by means of SEM,PM, XRD and DSC. It is shown that paraffin can be uniformly absorbed into the pore network of expanded graphite, that expanded graphite remains its vermiform structure in PCM, and there is not new substance formed in composite PCM, that the phase-change temperatures of composite PCM is similar to that of paraffin, and that the latent heat of composite PCM is equivalent to the calculated values based on the mass fraction of paraffin in the composite materials.