Effect of Magnesia/Phosphate Ratio on Hydration Processes of Magnesium Phosphate Cement

被引：0
|
作者：
Dai F. [1 ]
Wang H. [1 ]
Ding J. [1 ]
Jiang Z. [1 ]
机构：
[1] Department of Chemistry and Engineering, Logistical Engineering University, Chongqing
来源：
Wang, Hongtao (wht1969@163.com) | 1600年 / Chinese Ceramic Society卷 / 45期
关键词：
Hydration kinetics; Hydration mechanism; Magnesia/phosphate ratio; Magnesium phosphate cement;
D O I：
10.14062/j.issn.0454-5648.2017.08.13
中图分类号：
学科分类号：
摘要：
The influence of M/P ratio (mass ratio of magnesia to phosphate) on the hydration processes of magnesium phosphate cement (MPC) was investigated. The mechanism was analyzed via the hydration kinetic combined with the variation of hydration production and microstructure. The results show that increasing M/P ratio can decrease the peak value of endothermic valley and exothermic peaks of the hydration. The hydration of MPC is divided into six stages, i.e., hydrolyzation of KH2PO4, dissolution of MgO, growth of Mg(H2O)62+, accelerating growth of MgKPO4·6H2O, decelerate growth of MgKPO4·6H2O and stable period according to the change regulation of hydration evolution rate of MPC. The final heat release and half-life of MPC can be predicted by the Knudsen hydration equation, and the Kondo hydration equation can be applied for the hydration kinetic. The Pearson correlation coefficient of the fitting is >0.99. The final heat and half-life of MPC decreases when the M/P ratio increases from 2:1 to 6:1. The hydration of MPC varies from nucleation and crystal growth process to diffusion process directly. The M/P ratio mainly affects the growth of Mg(H2O)62+, decelerates the growth of MgKPO4·6H2O. The concentration of reactant and free water are the primary reasons for altering the hydration behavior of MPC. The partition function of residual MgO and the reactant concentration in hydration system determine the hydration behavior of MPC when the hydration proceeds into stage V and stage VI. © 2017, Editorial Department of Journal of the Chinese Ceramic Society. All right reserved.
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页码：1144 / 1152
页数：8
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