Phase change materials(PCMs)are promising thermal energy storage materials due to their high specific latent heat.Conventional PCMs typically exploit the solid–liquid(s–l)transition.However,leakage and leaching are ...Phase change materials(PCMs)are promising thermal energy storage materials due to their high specific latent heat.Conventional PCMs typically exploit the solid–liquid(s–l)transition.However,leakage and leaching are common issues for solid–liquid PCMs,which have to be addressed before usage in practical applications.In contrast,solid–solid(s–s)PCMs would naturally overcome these issues due to their inherent form stability and homogeneity.In this study,we report a new type of s–s PCM based on chemically linked polyethylene glycol(PEG,the PCM portion)with polylactic acid(PLA,the support portion)in the form of a block co‐polymer.Solid‐solid latent heat of up to 56 J/g could be achieved,with melting points of between 44°C and 55°C.For comparison,PEG was physically mixed into a PLA matrix to form a PEG:PLA composite.However,the composite material saw leakage of up to 9%upon heating,with a corresponding loss in thermal storage capacity.In contrast,the mPEG/PLA block co‐polymers were found to be completely homogeneous and thermally stable even when heated above its phase transition temperature,with no observable leakage,demonstrating the superiority of chemical linking strategies in ensuring form stability.展开更多
分别以聚乙二醇(PEG)、石蜡为相变物质,三元乙丙橡胶(EPDM)基吸油树脂为骨架支撑材料,通过吸油树脂对相变物质的吸附作用,制备了高分子固-固相变材料。使用红外光谱和差示扫描量热法对相变材料的结构和相变行为进行了研究;同时,采用偏...分别以聚乙二醇(PEG)、石蜡为相变物质,三元乙丙橡胶(EPDM)基吸油树脂为骨架支撑材料,通过吸油树脂对相变物质的吸附作用,制备了高分子固-固相变材料。使用红外光谱和差示扫描量热法对相变材料的结构和相变行为进行了研究;同时,采用偏光显微镜的反射模式对相变材料的动态相变过程进行了观察。研究结果表明:在相变储能材料中,相变物质石蜡与PEG的熔融相转变焓分别为140.8 k J/g和7.5 k J/g;结晶相转变焓分别为137.2 k J/g和2.8 k J/g;在动态升/降温的相转变过程中,可观察到相变物质在吸油树脂网络中的熔体流动/凝固状态;相变过程中相变物质未发生泄漏,具有可逆的相转变特性。展开更多
基金Science and Engineering Research Council,Grant/Award Number:GAP/2019/00314。
文摘Phase change materials(PCMs)are promising thermal energy storage materials due to their high specific latent heat.Conventional PCMs typically exploit the solid–liquid(s–l)transition.However,leakage and leaching are common issues for solid–liquid PCMs,which have to be addressed before usage in practical applications.In contrast,solid–solid(s–s)PCMs would naturally overcome these issues due to their inherent form stability and homogeneity.In this study,we report a new type of s–s PCM based on chemically linked polyethylene glycol(PEG,the PCM portion)with polylactic acid(PLA,the support portion)in the form of a block co‐polymer.Solid‐solid latent heat of up to 56 J/g could be achieved,with melting points of between 44°C and 55°C.For comparison,PEG was physically mixed into a PLA matrix to form a PEG:PLA composite.However,the composite material saw leakage of up to 9%upon heating,with a corresponding loss in thermal storage capacity.In contrast,the mPEG/PLA block co‐polymers were found to be completely homogeneous and thermally stable even when heated above its phase transition temperature,with no observable leakage,demonstrating the superiority of chemical linking strategies in ensuring form stability.
文摘分别以聚乙二醇(PEG)、石蜡为相变物质,三元乙丙橡胶(EPDM)基吸油树脂为骨架支撑材料,通过吸油树脂对相变物质的吸附作用,制备了高分子固-固相变材料。使用红外光谱和差示扫描量热法对相变材料的结构和相变行为进行了研究;同时,采用偏光显微镜的反射模式对相变材料的动态相变过程进行了观察。研究结果表明:在相变储能材料中,相变物质石蜡与PEG的熔融相转变焓分别为140.8 k J/g和7.5 k J/g;结晶相转变焓分别为137.2 k J/g和2.8 k J/g;在动态升/降温的相转变过程中,可观察到相变物质在吸油树脂网络中的熔体流动/凝固状态;相变过程中相变物质未发生泄漏,具有可逆的相转变特性。
