压缩二氧化硅/聚乙烯气凝胶复合薄膜的辐射制冷性质  

Radiative Cooling Properties of Compressed SiO_(2)/PE Aerogel Composite Films

作　　者：仪力菁 高杰[1] 苗蕾 YI Lijing;GAO Jie;MIAO Lei(School of Materials Science and Engineering,Guilin University of Electronic Technology,Guilin 541004,Guangxi,China;School of Physical Science and Technology,Guangxi University,Nanning 530004,China)

机构地区：[1]桂林电子科技大学材料科学与工程学院,广西桂林541004 [2]广西大学物理科学与工程技术学院,南宁530004

出　　处：《功能高分子学报》2024年第5期441-450,共10页Journal of Functional Polymers

基　　金：国家自然科学基金地区科学基金(51961011)。

摘　　要：利用热诱导相分离法和简单的压缩工艺制备了压缩二氧化硅/聚乙烯(SiO_(2)/PE)气凝胶复合薄膜,通过表征薄膜的微观结构和光学性能,研究了SiO_(2)添加量和气凝胶压缩程度对薄膜光学性能的影响。当纳米SiO_(2)、微米SiO_(2)、聚乙烯的质量比为0.5∶1∶1,压缩比(压缩后气凝胶薄膜厚度与未压缩气凝胶厚度之比)为1/9时,可得最佳样品。最佳样品具有96.4%的太阳光谱平均反射率和95%的大气窗口平均发射率,能通过自身辐射制冷能力获得最高6.5℃的温度降低,可对亚环境进行全天候冷却。A passive daytime radiative cooling thin film material has been developed to provide the cooling source which requires no input,sustainable,and no pollutants or greenhouse gases emission.The thermally induced phase separation method and simple compression were used to prepare the compressed composite silica dioxide/polyethylene(SiO_(2)/PE)aerogel films.The impact of SiO_(2) particle sizes and additions on the optical properties of composite films was investigated,and the internal microstructures and optical properties of the films were characterized.The optical properties of the films were enhanced by controlling the degree of compression.The results indicate that the addition of micro SiO_(2) is more favorable for increasing reflectance and nano SiO_(2) is more favorable for increasing emissivity,and the densification could result in emissivity enhancement and reflectance reduction.The optimal sample is achieved when the mass ratio of nano SiO_(2) to micro SiO_(2) to polyethylene is 0.5∶1∶1 and the compression ratio is one-ninth.This sample has a thickness of 0.5 mm,with 96.4%average reflectance of the solar spectrum and 95%average emissivity of the atmospheric window.The practical application performance of the sample was evaluated by testing its radiative cooling performance,antifouling and mechanical stability abilities.The experimental results show that the optimal sample achieves a significant temperature reduction of up to 6.5℃compared to the sub-environment.This indicates that the SiO_(2)/PE aerogel film has the ability to passively cool the sub-environment during both day and night,and that it has a contact angle with water of 127°,providing water resistance and potential self-cleaning properties in practical applications.

关 键 词：二氧化硅 聚乙烯 热诱导相分离 压缩 光学性能 辐射冷却 

分 类 号：O631.24[理学—高分子化学]