Microstructure and Characterization of Capric-stearic Acid/Modified Expanded Vermiculite Thermal Storage Composites  

作　　者：刘凤利 朱教群 LIU Junhua MA Baoguo ZHOU Weibing LI Ruguang QIN Weigao 

机构地区：[1]State Key Laboratory of Silicate Materials for Architecture, Wuhan University of Technology, Wuhan 430070, China [2]Laboratory for Recycled and Functional Building Materials, Henan University, Kaifeng 475004, China [3]School of Civil Engineering and Architecture, Kaifeng University, Kaifeng 475004, China [4]School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2018年第2期296-304,共9页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the Major State Research Development Program of China during the 13th Five-Year Plan Period(No.2016YFC0700904);the Science and Technology Support Program of Hubei Province(Nos.2014BAA134 and 2015BAA107)

摘　　要：In order to improve the thermal storage capacity of expanded vermiculite（EV） based formstable composite PCM（FS-PCM） via organic modification of EV, first, EV was modified with a sodium stearate（Na St） as surface modifier, and organic EV（OEV） with hydrophobicity and higher adsorption capacity for fatty acid was obtained. A novel capric-stearic acid eutectic（CA-SA）/OEV FS-PCM with high thermal storage capacity was then developed. OEV and CA-SA/OEV were characterized by scanning electron microscopy（SEM）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, differential scanning calorimetry（DSC）, thermal gravimetry（TG）, and thermal cycling test. Results showed that OEV has obvious hydrophobicity and a higher adsorption capacity for fatty acid. Its adsorption ratio has increased by 48.71% compared with that of EV. CA-SA/OEV possesses high thermal storage density（112.52 J/g）, suitable melting temperature（20.49 ℃）, good chemical compatibility, excellent thermal stability and reliability, indicating great application potential for building energy efficiency. Moreover, organic modification of inorganic matrix may offer novel options for improving its adsorption capacity for organic PCMs and increasing heat storage capacity of corresponding FS-PCMs.In order to improve the thermal storage capacity of expanded vermiculite（EV） based formstable composite PCM（FS-PCM） via organic modification of EV, first, EV was modified with a sodium stearate（Na St） as surface modifier, and organic EV（OEV） with hydrophobicity and higher adsorption capacity for fatty acid was obtained. A novel capric-stearic acid eutectic（CA-SA）/OEV FS-PCM with high thermal storage capacity was then developed. OEV and CA-SA/OEV were characterized by scanning electron microscopy（SEM）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, differential scanning calorimetry（DSC）, thermal gravimetry（TG）, and thermal cycling test. Results showed that OEV has obvious hydrophobicity and a higher adsorption capacity for fatty acid. Its adsorption ratio has increased by 48.71% compared with that of EV. CA-SA/OEV possesses high thermal storage density（112.52 J/g）, suitable melting temperature（20.49 ℃）, good chemical compatibility, excellent thermal stability and reliability, indicating great application potential for building energy efficiency. Moreover, organic modification of inorganic matrix may offer novel options for improving its adsorption capacity for organic PCMs and increasing heat storage capacity of corresponding FS-PCMs.

关 键 词：organic expanded vermiculite capric-stearic acid eutectic form-stable composite PCMs thermal energy storage building envelope 

分 类 号：TB34[一般工业技术—材料科学与工程]