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脂肪酸/无机纳米颗粒基定形相变材料的制备与热性能 总被引:2,自引:0,他引:2
以工业水玻璃为纳米SiO2前驱物,以癸酸(CA)和月桂酸(LA)二元低共熔酸为相变芯材,在表面活性剂的参与下,采用溶胶-凝胶法一步制备出纳米级复合定形相变蓄热材料.利用透射电子显微镜,扫描电子显微镜,傅里叶红外光谱仪,方差扫描量热法和热重分析等测试技术对此定形相变蓄热材料的结构和性能进行分析,并采用瞬态热线法测量了其导热系数.结果表明:相变芯材在吸热熔化后不会产生流动和渗漏;复合相变材料中脂肪酸含量(质量分数)为46%,具有良好的相变蓄热性能(相变温度19.57℃,相变潜热71.28 J/g)和热稳定性;复合相变材料导热系数为0.178 W/(m·K),可作为一种良好的隔热、保温建筑材料. 相似文献
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为解决真空浸渍法制备的石蜡/膨胀珍珠岩复合相变材料在相变过程中石蜡泄露等问题,采用白乳胶对石蜡/膨胀珍珠岩复合相变材料进行封装。利用FT-IR测试分析封装后定形相变材料的化学结构,封装后定形复合相变材料无新物质生成,化学相容性良好。采用SEM与压汞法对膨胀珍珠岩与定形复合相变材料的孔隙特征及载体基质对石蜡吸附性进行表征,结果表明膨胀珍珠岩对石蜡吸附性能良好。封装后25与32~#石蜡/膨胀珍珠岩定形相变材料的相变温度基本保持不变,相变焓分别72.13和121.2 J/g。采用热重曲线对封装前后石蜡基定形复合相变材料热物性进行研究,封装后的定形复合相变材料热稳定性提升11.95%。 相似文献
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采用本体聚合法分别制备了以癸酸、硬脂酸及两者的共熔"合金"作为蓄热介质,PMMA作基体的定形相变蓄热材料.用DSC、TGA、FT-IR、SEM等测试方法对蓄热材料的热性能、表面形态及相变材料与基体的相容性等进行了研究,结果表明,制备的定形相变蓄热材料具有合适的相变温度和较高的相变潜热,相交过程无液体泄露,相变材料在基体中分散均匀,两者相容性好,热性能稳定,可以应用于建筑节能和太阳能利用等领域. 相似文献
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孟多 《武汉理工大学学报(材料科学英文版)》2017,32(5):1048-1056
This work mainly involved the preparation of a nano-scale form-stable phase change material(PCM) consisting of capric and myristic acid(CA-MA) binary eutectic acting as thermal absorbing material and nano silicon dioxide(nano-SiO_2) serving as the supporting material. Industrial water glass for preparation of the nano silicon dioxide matrix and CA-MA eutectic mixture were compounded by single-step sol-gel method with the silane coupling agent. The morphology, chemical characterization and form stability property of the composite PCM were investigated by transmission electron microscopy(TEM), scanning electron microscopy(SEM), Fourier-transform infrared(FT-IR) spectroscopy and polarizing microscopy(POM). It was indicated that the average diameter of the composite PCM particle ranged from 30-100 nm. The CA-MA eutectic was immobilized in the network pores constructed by the Si-O bonds so that the composite PCM was allowed no liquid leakage above the melting temperature of the CA-MA eutectic. Differential scanning calorimetry(DSC) and thermogravimetric analysis(TGA) measurement were conducted to investigate the thermal properties and stability of the composite PCM. From the measurement results, the mass fraction of the CA-MA eutectic in the composite PCM was about 40%. The phase change temperature and latent heat of the composite were determined to be 21.15 ℃ and 55.67 J/g, respectively. Meanwhile, thermal conductivity of the composite was measured to be 0.208 W·m~(-1)·K~(-1) by using the transient hot-wire method. The composite PCM was able to maintain the surrounding temperature close to its phase change temperature and behaved well in thermalregulated performance which was verified by the heat storage-release experiment. This kind of form-stable PCM was supposed to complete thermal insulation even temperature regulation by the dual effect of relatively low thermal conductivity and phase change thermal storage-release properties. So it can be formulated that the nanoscale CA-MA/SiO_2 composite PCM with the form-stable property, good thermal storage capacity and relatively low thermal conductivity can be applied for energy conservation as a kind of thermal functional material. 相似文献
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黄建兵宁铎曹继春孟多 《中国皮革》2017,(7):30-32
在空间上通过刀口平面与皮样表面以一定角度相交方式,把原来以刀口周长为线段与皮样以线接触方式,改进为整个切割过程中呈现为点接触方式,从而使得制作皮样所需压力大幅减小;在时间上把原来瞬间完成切割改为持续施力的过程。通过空间和时间上的变化并以此为原理制作的取样器结构简单,操作方便。 相似文献