以膨胀石墨为基础,以硬脂酸(SA)为相变材料,制备了硬脂酸复合相变材料(SPCM),通过测试加入复合相变材料的磷酸镁水泥(MPC)的水化性能,探究SPCM对MPC水化热性能的影响。结果表明,SPCM不参与MPC的水化反应,而是与MPC物理结合,使其保持自身属性;随着SPCM含量的增加,MPC孔隙率增加,孔径主要分布在100~1000nm,导热性能略有下降,且相同龄期内,水化产物MgKPO4·6H2O的含量有所降低,热稳定性提高;SPCM通过相变吸放热和导热性能的变化,使MPC水化体系的放热速率减慢,放热量减少,内部温度降低,达到了减小温度应力和保持体系稳定的目的,保证了MPC体系的结构稳定和性能优良。
The stearic acid composite phase change materials (SPCM) were prepared by melt blending method with stearic acid (SA) as phase change material and expanded graphite (EG) as packing material. It is to explore the effect of SPCM on the thermal properties of magnesium phosphate cement(MPC) by testing the properties of MPC with SPCM. Results showed that SPCM don't par- ticipate in the hydration reaction of the MPC,but thephysical union with MPC,to keep its own properties of MPC. Along with the increase of the content of SPCM,the porosity of MPC increases,the aperture is mainly distributed from 100 to 1000 nm, heat conduc- tion performance decreases slightly, and in the period of the same age,hydration products MgKPO4·6H2O content decreases and the thermal stability increases. The hydration heat release rate of MPC system slows,heat quantity reduces and the internal temperature decreases SPEM by the change of the phase change and heat conduction performance. It can decrease the temperature stress and maintain stability of the system to guarantee the stability of the structure of the MPC system and excellent performance.