高定形聚乙二醇/剑麻纤维素/膨胀石墨相变储能材料的研制及热性能

Preparation and Thermal Properties of Polyethylene Glycol/Cellulose of Sisal Fiber/Expanded Graphite High Form-Stabilized Phase change Materials

以聚乙二醇(PEG)作为相变组分,以高导热的膨胀石墨(EG)和富含羟基的剑麻纤维素(CSF)作为相变支撑组分,分别利用自制的超声辅助真空设备进行动态灌注或机械搅拌进行熔融共混制备了不同PEG用量的定形相变储能材料(PCMs)。采用扫描电子显微镜、高分辨率光学相机、差示扫描量热仪、Hot disk-导热仪、热重分析仪等技术测试了PEG基复合PCMs的微观形貌、定形性、储热性能、导热率及稳定性。结果表明,新颖的动态灌注法制备的PEG基复合相变材料呈现出更致密的微观形态,更好的储热性能和更高的导热率及热稳定性。同时,实验发现由于CSF大量的极性羟基和多孔隙结构,当CSF质量分数为30%,EG质量分数为1%时,复合材料表现出极好的定形效果。

With polyethylene glycol （PEG） as a phase change components, expanded graphite （EG） of high thermal conductivity and cellulose of sisal fiber （CSF） in rich hydroxyl as a phase change support components, homemade ultrasonic auxiliary vacuum equipment dynamic perfusion or mechanical stirring melt-blending was adopted to prepare phase change materials （PCMs） as a function of different components ratio, respectively. SEM, high resolution optical camera, differential scanning calorimetry （ DSC ）, Hot disk-thermal conductivity, thermogravimetrie （TG） were used to test the microstructure, form-stabilized properties, thermal conductivity and stability of PEG-matrix composite PCMs. The results show that the PEG-matrix composite PCMs via dynamic impregnating have stronger interaction, better thermal performance and higher thermal conductivity and thermal storage stability, compared with that of mechanical stirring melt-blending. Notably, because of amounts of polar hydroxyl and pore structure of CSF, when the mass fraction of CSF is 30 %, EG is 1%, the composites show an excellent form-stabilized effect.