“十三五”国家重点研发计划项目(2017YFB0309903 03)；陕西省重点研发计划项目(2017GY 142,2017GY 176)；陕西省自然科学基金资助项目(2017JM5097)
采用X射线衍射（XRD）和固体魔角核磁共振硅谱（29Si MAS NMR）技术，研究了不同养护温度下MgO/SiO2体系水化产物的结构特征.结果表明：死烧MgO比轻烧MgO衍射峰强度更大；水化硅酸镁(MSH)凝胶呈结晶性较差、短程有序的层状硅酸盐结构；MSH含量随着养护温度的升高而增多，相同养护温度下MSH的含量随着龄期的延长而增多,50℃下养护28d的试样MSH含量最多；养护温度过高会抑制MSH的生成；高温养护有利于Q1向Q2、Q2向Q3转化，使得MSH硅氧四面体聚合度提高.
The structural feature of hydration products of MgO/SiO2 system under different curing temperatures was investigated by X ray diffraction(XRD) and 29Si magic angle spinning nuclear magnetic resonance(29Si MAS NMR) respectively. The results reveal that the diffraction peak intensity of dead burning MgO is higher than that of soft burning MgO. M S H gel is layered silicate which is poorly crystalline of short range ordered structures. The content of M S H increases with the rising of curing temperature；under the same curing temperature the content of M S H increases with prolongation of hydration time. When the age is 28d and curing temperature is 50℃, the content of M S H is at the most. But the formation of M S H is suppressed when the curing temperature is too high. High curing temperature is favorable for the conversion of Q1 to Q2 and Q2 to Q3 and is beneficial for polymerization degree of silica.
肖建敏,胡亚茹,宋强.养护温度对MgO/SiO2体系水化产物微观结构的影响[J].建筑材料学报,2018,21(6):871-877
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