硬脂酸-月桂酸二元复合相变材料

以硬脂酸(SA)、月桂酸(LA)为原料,通过熔融共混法制备了二元脂肪酸相变材料。采用红外光谱(FTIR)、偏光显微镜(POM)、差示扫描量热仪(DSC)及温度记录仪分别表征了共混相变材料的结构、结晶形态、相变温度和焓值以及保温性能。FTIR表明共混相变材料中硬脂酸与月桂酸通过分子间作用力结合在一起;POM表明SA与LA在共混物中形成共晶结构,且随SA/LA质量配比的减小,结晶半径减小;DSC表明共混相变材料的结晶焓达到200J/g,随SA/LA质量配比的减小结晶温度先降低后升高,表现出低共熔物特征;步冷曲线表明,随SA/LA质量配比的减小,平台温度先降低后升高,且当SA/LA质量比为1/2时,温度平台为30.9℃,保温时间为25min,约为纯硬脂酸或月桂酸保温时间的2倍。

Binary multiple stearic acid/lauric acid phase change material

With stearic acid(SA),lauric acid(LA) as raw materials,the binary of fatty acids phase change materials were prepared by melt blending.Phase change temperature and latent heat of the SA/SA PCM were characterized using differential scanning calorimetry(DSC).The structure,crystalline morphology,and thermal insulation properties of the SA/LA PCM were investigated using fourier transformation infrared spectroscope(FTIR),polarizing optical microscopy(POM),and temperature-recording instrument.The FTIR and POM results showed that SA and LA was combininged by intermolecular forces,and SA/LA PCM was formed eutectic structure,moreover,the radius of crystal reduced with decrement of the SA/LA ratio.The DSC results indicated that SA/LA PCM had high latent heat storage capacity of more than 200 J/g.With the reducing SA/LA ratio,crystallization temperature reduced first and then increased,showing the performance characteristics of eutectic mixture.Cooling curves of SA/LA PCM showed that with the reducing SA/LA ratio,the platform temperature reduced first and then increased,and when the SA/LA was equal to 1/2,the temperature platform appeared at 30.9 ℃,the soaking time was continued for about 25 min twice as long as that of pure SA or LA.