石膏硬化体的显微结构对其表面吸湿性能的影响

Effect of Microstructure of Hardened Gypsum on Its Surface Moisture Absorption

采用氮吸附法对不同水膏比形成的石膏硬化体多孔材料的比表面积、总孔容积和孔径分布进行测试,利用饱和盐溶液法试验研究了石膏硬化体多孔材料表面吸湿性能,分析石膏硬化体多孔材料的显微结构对其表面吸湿性的影响,并通过SEM扫描电镜进一步分析形貌对吸湿性能的影响。结果表明:水膏比小的石膏硬化体比表面积大,在相对湿度较低情况下,表面吸湿性较高;水膏比大的石膏硬化体大孔含量多,在相对湿度较高情况下,表面吸湿性较高。

The specific surface area, pore volume and pore radius distribution of hardened gypsum with different water-gypsum ratios have been measured by nitrogen adsorption method. The property of the surface moisture absorption of hardened gypsum porous material has been tested by saturated salt solutions,and the effect of its microstructure on the surface moisture absorption has been analyzed. The morphology for hardened gypsum was analyzed by means of scanning electron microscopy. The results show that hardened gypsum with the small water-gypsum ratios has higher surface moisture content as its the large specific surface area at low relative humidity and the one with the large water-gypsum ratios has more macropores and higher equilibrium surface moisture content at high relative humidity.