石蜡/不同粒径膨胀石墨复合相变储热材料的制备和性能

Preparation and Performance of a Phase Change Heat Storage Composite of Paraffin/Different Particle Sized Expanded Graphite

用熔融共混法制备石蜡/不同粒径膨胀石墨复合相变储热材料,对样品进行XRD、FT-IR、SEM、DSC和LFA表征分析,研究了不同粒径膨胀石墨的质量比例对复合相变储热材料性能的影响。结果表明:随着小粒径膨胀石墨含量的增加,复合相变储热材料的热扩散系数先增大后减小。在大小粒径膨胀石墨质量比例为9∶1时,石蜡充分利用了大小粒径膨胀石墨的镶嵌式空间结构,复合相变材料的热扩散系数为1.964×10-6m2/s,比纯石蜡提高了22倍,相变潜热为144.2 J/g。

As phase change heat storage material(PCM), composites of paraffin/expanded graphite of different particle sizes(DPS-EG) were prepared by melt blending method, which were then characterized by means of XRD, FT- IR, SEM, DSC and LFA. The effect of mass fraction of DPS- EG on performance of the composite PCM was studied. Results show that the thermal diffusivity of the composite PCM increased first and then decreased with the increasing mass fraction of small particle sized EG.When the ratio of mass fraction for large sized ones to the small ones of the DPS-EG was 9:1, paraffin may be allowed to fill fully into the free space of the mosaic structure of DPS-EG. The thermal diffusivity of the composite PCM was up to 1.964×10- 6m2/s, 22 times higher than that of pure paraffin, while its latent heat was 144.2 J/g.