摘要
为实现相变材料温度调控,解决实际应用中的漏液问题,首先,以癸酸和棕榈酸甲酯为原料,采用熔融共混法制备了二元有机共晶相变材料(EPCM);然后,以柠檬酸(CA)、羧基化纤维素纳米纤维分散液(CNF)和FeCl_(3)•6H_(2)O为原料,采用溶胶-凝胶法制备了双交联CA-Fe^(3+)-CNF-Fe_(2)O_(3)气凝胶;最后,以气凝胶为载体负载EPCM,制备了复合定形相变材料(CA-PCM)。通过步冷曲线、二元相图和DSC测试,确定了癸酸和棕榈酸甲酯的共晶点;通过SEM考察了CA质量分数(以CA和CNF总质量计,下同)对其微观形貌的影响;通过FTIR、XRD、DSC、TGA对EPCM、气凝胶及CA-PCM进行了表征和测试;将CA-PCM作为保温材料,测试了其在建筑模型中的热缓冲性能。结果表明,m(癸酸)∶m(棕榈酸甲酯)=61∶39为癸酸和棕榈酸甲酯的实际共晶点,两者通过物理混合形成共晶体系(EPCM1),其相变温度为24.3℃、相变焓值为172.4 J/g;CA质量分数为1%制备的1%CA-Fe^(3+)-CNF/Fe_(2)O_(3)气凝胶孔更多且均匀,形貌更加规整;以1%CA-Fe^(3+)-CNF/Fe_(2)O_(3)气凝胶为骨架负载EPCM1,负载率达到85.57%,制备的1%CA-PCM相变温度为24.7℃、熔化焓值为125.2 J/g,经100次冷热循环后,相变温度和相变焓值没有显著变化;与使用塑料泡沫的泡沫模型相比,以1%CA-PCM为建筑保温材料的PCM模型升温时长增加了51.3%,降温时间延长了43.5%。
In order to achieve the temperature regulation on phase change materials and solve the problem of leakage in practical applications,binary organic eutectic phase change materials(EPCM)were prepared by melting blending method using capric acid and methyl palmitate as raw materials,while double cross-linked CA-Fe^(3+)-CNF-Fe_(2)O_(3)aerogels were synthesized from citric acid(CA),carboxylated cellulose nanofiber dispersion(CNF)and FeCl_(3)•6H_(2)O by sol-gel method.The composite stereotyped phase change materials(CA-PCM)were finally obtained by loading EPCM with double cross-linked CA-Fe^(3+)-CNF-Fe_(2)O_(3)aerogels as carriers.The eutectic point of capric acid and methyl palmitate was determined by step cooling curve,binary phase diagram and DSC.The influence of CA mass fraction(based on the total mass of CA and CNF,the same below)on its micromorphology was analyzed by SEM.The EPCM,aerogel and CA-PCM were characterized and tested by FTIR,XRD,DSC,TGA,followed by assessment on the thermal buffering performance of CA-PCM as insulation material in building models.The results showed that m(capric)∶m(methyl palmitate)=61∶39 was the actual eutectic point of capric acid and methyl palmitate,and the eutectic system(EPCM1)was formed by physical mixing,with the phase transition temperature of 24.3℃and the enthalpy of phase change of 172.4 J/g.The aerogel 1%CA-Fe^(3+)-CNF/Fe_(2)O_(3)prepared with a mass fraction of 1%CA was of much more uniform pores and more regular morphology.When 1%CA-Fe^(3+)-CNF/Fe_(2)O_(3)aerogel as skeleton was loaded with EPCM1,the loading rate reached 85.57%,while the 1%CA-PCM obtained exhibited a phase transition temperature of 24.7℃,and the melting enthalpy value of 125.2 J/g.Moreover,the phase change temperature and enthalpy value did not show significant change after 100 cold and thermal cycles.Compared with that of the plastic foam model,the heating time of the PCM model using 1%CA-PCM as building insulation material was increased by 51.3%and the cooling time was extended by 43.5%.
作者
李金芝
郝玉鹏
吴亚楠
张文琪
唐炳涛
张宇昂
LI Jinzhi;HAO Yupeng;WU Ya'nan;ZHANG Wenqi;TANG Bingtao;ZHANG Yuang(State Key Laboratory of Fine Chemicals,Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《精细化工》
北大核心
2026年第1期60-68,124,共10页
Fine Chemicals
基金
国家重点研发计划项目(2022YFB3806500)
国家自然科学基金项目(22108026、22108050)。
关键词
有机共晶相变材料
羧基化纤维素纳米纤维
气凝胶
定形复合相变材料
建筑节能
功能材料
organic eutectic phase change materials
carboxylated cellulose nanofibers
aerogels
steroeotyped composite phase change materials
energy efficiency in buildings
functional materials
