Abstract:
This study aims to use beeswax, a readily available and cost-effective organic material, as a novel phase change material (PCM) within blends of low-density polyethylene (LDPE) and styrene-b-(ethylene-co-butylene)-b-styrene (SEBS). LDPE and SEBS act as support materials to prevent beeswax leakage. The physicochemical properties of new blended phase change materials (B-PCM) were determined using an X-ray diffractometer and an infrared spectrometer, confirming the absence of a chemical reaction within the materials. A scanning electron microscope was used for microstructural analysis, indicating that the interconnection of the structure allowed better thermal conductivity. Thermal gravimetric analysis revealed enhanced thermal stability for the B-PCM when combined with SEBS, especially within its operating temperature range. Analysis of phase change temperature and latent heat with differential scanning calorimetry showed no major difference in the melting point of the various PCM blends created. During the melting/solidification process, the B-PCMs possess excellent performance as characterized by W70/P30 (112.45 J.g-1) > W70/P20/S10 (94.28 J.g-1) > W70/P10/S20 (96.21 J.g-1) of latent heat storage. Additionally, the blends tend to reduce supercooling compared to pure beeswax. During heating and cooling cycles, the B-PCM exhibited minimal leakage and degradation, especially in blends containing SEBS. In comparison to the rapid temperature drop observed during the cooling process of W70/P30, the temperature decline of W70/P30 was slower and longer, as demonstrated by infrared thermography. The addition of LDPE to the PCM reduced melting time, indicating an improvement in the thermal energy storage reaction time to the demand. According to the obtained findings, increasing the SEBS concentration in the composite increased the thermal stability of the resulting PCM blends significantly. Despite the challenges mentioned earlier, SEBS proved to be an effective encapsulating material for beeswax, whereas LDPE served well as a supporting material. Leak tests were performed to find the ideal mass ratio, and weight loss was analyzed after multiple cycles of cooling and heating at 70 °C. The morphology, thermal characteristics, and chemical composition of the beeswax/LDPE/SEBS composite were all examined. Beeswax proves to be a highly effective phase change material for storing thermal energy within LDPE/SEBS blends.
摘要:
本研究旨在使用蜂蜡,一种容易获得且具有成本效益的有机材料,作为低密度聚乙烯(LDPE)和苯乙烯-b-(乙烯-共-丁烯)-b-苯乙烯(SEBS)的共混物中的新型相变材料(PCM)。LDPE和SEBS充当支撑材料以防止蜂蜡泄漏。用X射线衍射仪和红外光谱仪测定了新型共混相变材料(B-PCM)的理化性质,确认材料内不存在化学反应。使用扫描电子显微镜进行微观结构分析,这表明该结构的互连允许更好的导热性。热重分析显示,当与SEBS结合使用时,B-PCM的热稳定性增强,特别是在其工作温度范围内。使用差示扫描量热法对相变温度和潜热的分析表明,所产生的各种PCM共混物的熔点没有重大差异。在熔化/凝固过程中,B-PCM具有W70/P30(112.45J.g-1)>W70/P20/S10(94.28J.g-1)>W70/P10/S20(96.21J.g-1)的潜热存储。此外,与纯蜂蜡相比,该共混物倾向于降低过冷度。在加热和冷却循环期间,B-PCM表现出最小的泄漏和降解,特别是在含有SEBS的混合物中。与在W70/P30的冷却过程中观察到的快速温度下降相比,W70/P30的温度下降更慢和更长,如红外热成像所示。向PCM中添加LDPE减少了熔融时间,表明热能储存反应时间对需求的改善。根据获得的发现,增加复合物中的SEBS浓度显著增加所得PCM共混物的热稳定性。尽管前面提到的挑战,SEBS被证明是一种有效的蜂蜡封装材料,而LDPE作为支撑材料很好。进行泄漏测试以找到理想的质量比,在70°C下多次冷却和加热循环后分析重量损失。形态学,热特性,研究了蜂蜡/LDPE/SEBS复合材料的化学组成。蜂蜡被证明是用于在LDPE/SEBS共混物内储存热能的高效相变材料。