Thermal energy storage and ionizing radiation resistance of multifunctional phase change microcapsules
Binary composite eutectic phase change material(PCM)was firstly prepared from n-tetradecane and n-octadecane.Multifunctional phase change microcapsules(MPCM)were then synthesized by self-assembly method and chemical precipitation method using PCM as core material and BaCO3 as wall material,characterized by FTIR,SEM,TGA,DSC,and added to cement slurry to further obtain cement samples with different MPCM content(based on the mass of standard cement,the same below),which were evaluated by Micro-CT device and XCOM calculation code for their X ray shielding ability.The results showed that MPCM exhibited the capacity of heat storage and ionizing radiation resistance,and presented in ovoid or spheroidal shape with a median particle size of 16.4 μm.The core-shell structure effectively maintained the heat storage density of MPCM through the intermolecular force connection.MPCM showed an initial phase change temperature of 1.22℃,latent heat(enthalpy of melting and enthalpy of crystallization)of-122.18 and 81.98 J/g,respectively,and encapsulation rate of 79.99%.After 80 thermal cycles,the phase change temperature remained unchanged,and the average latent heat decreased by only 6.56 J/g.MPCM could significantly enhance the radiation shielding effect of cement samples.The linear attenuation coefficient of the cement sample MCP10 prepared with 10%content MPCM was increased by 42.2%compared with that of the cement sample without MPCM.
phase change materialsmultifunctionthermal storage and energy savingionizing radiation shieldingfunctional materials
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维普
