磷酸镁水泥耐水性的研究  

Research on Water Resistance of Magnesium Phosphate Cement

作　　者：李东旭[1] 李鹏晓[1] 冯春花[1] 

机构地区：[1]南京工业大学材料化学工程国家重点实验室,江苏南京210009

出　　处：《建筑材料学报》2009年第5期505-510,共6页Journal of Building Materials

基　　金："十一五"国家科技支撑计划(2006BAF02A24)

摘　　要：研究了不同养护条件对磷酸镁水泥(MPC)力学、收缩性能的影响,以及不同原料配比对MPC耐水性的影响,并对不同养护条件下MPC水化产物的成分和微观结构进行了分析.结果表明:水养条件下MPC的28 d强度发生较大倒缩,耐水性较差;原料配比对MPC耐水性的影响较大,磷酸盐含量对MPC耐水性影响显著.MPC耐水性差的主要原因是水养条件下基体中少量未反应的磷酸盐溶出,改变了水溶液的pH值环境,导致主要水化产物MgKPO4.6H2O在酸性环境下水解,使体系孔隙率增大,强度倒缩.Effect of different curing conditions on the mechanical and shrinkage properties of magnesium phosphate cement（MPC）,the water resistance of MPC with different ratio of n（MgO） to n（KH_2PO_4）,the component and microstructure of the hydrated product were studied in this paper.The findings show that the strength of MPC loses greatly when cured in water for 28 d,which indicates that MPC has poor water resistance.The component of raw materials affects the water resistance greatly,and the amount of phosphate has the prominent influence.The primary reason is that some phosphate which has not reacted is dissolved when cured in water for days,it changes the pH value of the solution,so the main hydration product—MgKPO4·6H2O dissolves under acid environment resulting in the increasing of porosity and the decrease of strength.

关 键 词：磷酸镁水泥(MPC) 耐水性 养护制度 机理 

分 类 号：TQ177.5[化学工程—硅酸盐工业]