| 摘要: |
| 基于有机聚合物乳液的吸附及络合作用，采用丙烯酸乳液（AE）对氯氧镁水泥（MOC）进行改性，对改性后的MOC工作性能、力学性能、耐水性能及微观结构进行研究，揭示AE对MOC的改性机理. 结果表明：AE在MOC中的分散作用可增大MOC的流动度；AE在水泥颗粒及水化产物表面形成的膜结构在抑制5·1·8相晶体生长的同时，还改变了晶体形态，对MOC的凝结时间及强度产生了影响；AE不仅降低了MOC内部有害孔的体积分数，还在MOC内部形成了膜结构，在这两者共同作用下，5·1·8相晶体的水解得以延缓，Mg（OH）2晶体的生成量减少，从而改善了MOC的耐水性能. |
| 关键词: 氯氧镁水泥 丙烯酸乳液 力学性能 耐水性能 微观结构 |
| DOI：10.3969/j.issn.1007-9629.2024.06.001 |
| 分类号:TU526 |
| 基金项目:“十四五”国家重点研发计划项目（2022YFC3803400） |
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| Properties of Acrylic Emulsion Modified Magnesium Oxychloride Cement and Its Mechanism |
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LI Xiaoqing1, BIAN Libo1, DING Linna1, ZHANG Lu2, WEI Xia3
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1.School of Civil and Transportation Engineering， Beijing University of Civil Engineering and Architecture， Beijing 100044，China;2.Beijing Shoufa Tianren Ecological Landscape Co.， Ltd.， Beijing 102600，China;3.Beijing National Union Standard Certification Co.， Ltd.， Beijing 100831，China
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| Abstract: |
| The adsorption and complexation of organic polymer emulsion， acrylic emulsion （AE） was used to modify magnesium oxychloride cement （MOC）. The working properties， mechanical properties， water resistance and microstructure of modified MOC were systematically investigated， and the mechanism of the modification of MOC by AE was revealed. The results show that the dispersing effect of AE in MOC can increase the fluidity. AE formed membrane structures on the surface of cement particles and hydration products not only inhibit 5·1·8 phase crystals growth， but also change its morphology so as to influence the setting time and strength of MOC. Meanwhile， AE reduces the volume fraction of harmful pores of MOC. Combined with the membrane structure generated by AE inside the MOC， it can delay the hydrolysis of 5·1·8 phase crystals and reduce the generation of Mg（OH）2 crystals. Thus， the water resistance of the MOC is improved. |
| Key words: magnesium oxychloride cement（MOC） acrylic emulsion（AE） mechanical property water resistance microstructure |
