外墙复合相变贴片材料相变及隔热性能研究

Study on thermal insulation performance of composite phase change patch materials for exterior walls

以石蜡(Paraffin)为相变原材料,膨胀石墨(EG)为载体,借助膨胀石墨具有独特网状空隙结构和良好吸附的特性,利用熔融吸附法制备了石蜡/膨胀石墨复合相变材料,并将其与水泥混合制备了应用于建筑外墙的复合相变贴片材料,并对相关性能进行了测试。实验结果表明,90%石蜡含量能够使膨胀石墨吸附量达饱和,相变温度为41.1℃,与纯石蜡相比略有降低;相变潜热为224.7 J/g,与理论计算值相差1.14%,SEM及XRD分析结果显示,石蜡与膨胀石墨之间具有很好地热稳定性和相容性。隔热性能测试实验显示,与瓷砖贴片材料相比,惨入复合相变材料的复合相变贴片材料能够将内表面最高温度降低2.4℃,有效阻隔进入室内的热量,改善围护结构的隔热性能,具有有效降低建筑空调能耗应用潜力。

Paraffin was the raw material,and the expanded graphite was chosen as absorbing material for having unique network space structure and good adsorption capacity.The paraffin/expanded graphite(EG)composite phase change material was prepared,and then cement was added to prepare phase change patch material to the external wall.Some properties were tested.The results showed that the maximum absorption of expanded graphite was 90wt%,and the phase change temperature of paraffin/expanded graphite composite phase change material was 41.1℃,the phase change latent heat was 224.7 J/g.The latent heat has 1.14%deviation to the theoretical value.And the scanning electron microscope(SEM)and X-Ray Powder Diffraction(XRD)analysis showed that both paraffin and expanded graphite had good compatibility and stability.Comparing with ceramic tiles,the experiment results showed that the composite phase change patch material could effectively improve the insulate performance to walls,the maximum temperature decreased by 2.4℃,it could effectively reduce the heat to enter the room,and has potential to reduce the energy consumption of air conditioning in buildings.