关键词: 磷建筑石膏;缓凝剂;水化热;力学性能

Abstract: In this experiment , we have researched the effects of different types of retarders on phosphor building gypsum setting time and mechanical strength , and text the dry density and hydration heat of phosphor building gypsum after added different types of retarders .The phase composition of the plaster was studied by XRD , and the microstructure of modified plaster was studied by SEM .The research finding shows that NS , NP and SC have a certain retardation effect on phosphorus building gypsum , but the effect is different , the best effect of retardation is SC;In the case of the same amount of content , the maximum effect on the strength of the hardened body of the gypsum is SC , and its effect on the dry density of hardened body in phosphorus building gypsum is also the greatest .SC can make the hydration heat of the phosphorus building gypsum delayed , and reducing the hydration exothermic peak .The suitable dosage range of SC is 0.1％-0.2％.The experimental results provide a reference value for the further study of the retardation mechanism of phosphorus building gypsum .

Key words: phosphor building gypsum;retarder;hydration heat;mechanical property