| 摘要: |
| 采用成膜微胶囊及喷雾干燥工艺制备了有机硅微胶囊粉末防水剂.试验研究了有机硅微胶囊粉末防水剂相对表面含油量、防水抗渗性能及其对水泥基材抗压强度、收缩性能以及孔结构等的影响.结果表明：有机硅微胶囊粉末防水剂的防水效果优于液态聚二甲基硅氧烷（PDMs）防水剂；采用3%（质量分数）辛基三乙氧基硅氧烷替代聚二甲基硅氧烷，砂浆浸水48h的吸水率可降低至3%～4%，抗渗压力增大489%，加载90d龄期的砂浆收缩率减少68%.扫描电镜（SEM）表明：微胶囊粉末防水剂为内核外壳结构，其中活性有机硅芯材与纳米碳酸钙填料被聚乙烯醇成膜包裹在其内部；经水解后，水溶性聚乙烯醇膜吸胀溶解，活性有机硅成分释放，参与形成有机硅疏水膜，起到防水效果，并提高了水泥水化程度，增强了基材密实性. |
| 关键词: 干粉砂浆 有机硅微胶囊粉末防水剂 成膜微胶囊 作用机理 |
| DOI：103969/jissn1007 9629201503013 |
| 分类号: |
| 基金项目: |
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| Mechanism and Working Performance of Organic Silicone Microcapsule Powder Water Repellent |
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HE Yan, ZHANG Xiong, ZHANG Yongjuan, XIA Xiaodan
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Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education,Tongji University, Shanghai 201804, China
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| Abstract: |
| Organic silicone microcapsule powder water repellent was prepared through film forming microcapsule technology and spray drying technology. Performance of organic silicone powder water repellent was evaluated in terms of relative surface oil content, productive rate, mean particle size, morphology, waterproof property, anti penetrability property and influence on compressive strength and shrinkage rate of cement based materials. The effect of organic silicone microcapsule powder water repellents was superior to that of liquid polydimethylsiloxane（PDMs）. With 3% content（by mass） of octyl triethoxy silane substituting for PDMs, core material of organic silicone water repellent was optimized, the water absorption rate of mortar after soaking for 48h decreased to 3%4%, impermeability pressure increased by 489%, and shrinkage rate decreased by 68% at 90d loading age. It is indicated from SEM analysis that organic silicone microcapsule powder water repellent is of core shell structure, with active organic silicone core materials and nano calcium carbonate fillers wrapped with polyvinyl alcohol and distributed inside. After hydrolysis, water soluble polyvinyl alcohol is dissolved, and active organic silicone core material was gradually released, which participated in the formation of organic silicone hydrophobic membrane and made effects for waterproofing, and for the improvement of hydration degree and structure compactness. |
| Key words: dry mixed mortar organic silicone microcapsule powder water repellent film forming microcapsule function mechanism |
