随着人们对室内热舒适度要求的不断提高,近年来建筑能耗逐渐上升.因此,被动节能材料受到广泛关注.相变材料和调湿材料是可用于建筑物的两种重要的被动节能材料.相变材料通过在相变过程中吸收或释放热量来调节室内温度,调湿材料可以依据自身特性自动调节室内的相对湿度.值得注意的是,现有的研究大多数都是单独分析相变材料或调湿材料,结合两者性能的研究却很少,限制了它们在建筑中的应用.为了研究相变材料和调湿材料的复合性能,本文以石蜡为相变材料,膨胀珍珠岩为载体材料,通过真空吸附法制备复合相变颗粒.将复合相变颗粒在自制的模具里压制成相变板材,最后在相变板材上喷涂调湿材料硅藻泥,制得具有调湿性能的复合相变墙板.利用XRD、物理吸附分析仪、SEM、DSC对物质组成、孔径、微观结构、热物理性能进行了表征,复合相变颗粒对调湿材料的平衡含湿量和循环吸放湿性能进行了测试,同时,对具有调湿性能的复合相变墙板进行性能测试.结果表明:(1)复合相变墙板具有适宜的相变参数,熔点/凝固点分别为18.23℃/29.42℃,高潜热值分别为54.66 J/g和55.63 J/g.(2)经过循环吸放湿测试后,硅藻泥的吸湿量总是高于放湿量,且吸湿量和放湿量有微弱的衰减,但硅藻泥的调湿性能相对稳定.(3)硅藻泥在不同温度下(T=10℃,25℃,40℃;RH=85％)的调湿性能随着温度的升高而降低,在不同湿度下(RH=75％,85％,90％;T=25℃)随着湿度的增加而增强.(4)相变材料和硅藻泥耦合,两者相互作用对各自的效果有正向加强作用,可以有效调节室内温湿度.%Phase change material (PCM) can reduce the indoor temperature fluctuation and humidity control material can adjust relative humidity used in buildings. In this study, a kind of composite phase change material particles (CPCMPs) were prepared by vacuum impregnation method with expanded perlite (EP) as supporting material and paraffin as phase change material. Thus, a PCM plate was fabricated by mould pressing method with CPCMPs and then composite phase change humidity control wallboard (CPCHCW) was prepared by spraying the diatom mud on the surface of PCM plate. The composition, thermophysical properties and microstructure were characterized using X-ray diffraction instrument (XRD), differential scanning calorimeter (DSC) and scanning electron microscope (SEM). Additionally, the hygrothermal performance of CPCHCW was characterized by temperature and humidity collaborative test. The results can be summarized as follows: (1) CPCMPs have suitable phase change parameters with melting/freezing point of 18.23 ℃/29.42 ℃ and higher latent heat of 54.66 J/g/55.63 J/g; (2) the diatom mud can control the humidity of confined space with a certain volume; (3) the combination of diatom mud and PCM plate in CPCHCW can effectively adjust the indoor temperature and humidity. The above conclusions indicate the potential of CPCHCW in the application of building energy efficiency.
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