| 摘要: |
| 采用体式显微镜观察高吸水树脂（SAP）在早龄期压榨孔溶液及真实水泥浆体环境中的粒径变化，分析了SAP在水泥浆体早期硬化过程中的释水行为.结果表明：SAP在压榨孔溶液中的饱和平衡吸水倍率变化不能反映其在水泥浆体中的释水行为；SAP在水泥浆体早期塑性阶段就表现出快速释水，在浆体凝结后短时间内再次快速释水，之后缓慢释水；SAP在水泥浆体塑性阶段释水能够降低其毛细管压力，有助于降低水泥浆体的塑性收缩，但不利于抑制水泥浆体硬化后的自收缩. |
| 关键词: 高吸水树脂 释水行为 真实水泥浆体环境 毛细管压力 自生体积变形 |
| DOI：10.3969/j.issn.1007-9629.2022.02.001 |
| 分类号:TU528.32 |
| 基金项目:广东省重点领域研发计划项目（2019B111106002） |
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| Desorption Behavior of Super Absorbent Polymer in Cement Paste during Harden Process |
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LI Ming1, XU Wen2, WANG Kangchen3, WU Lingzheng3, LIU Jiaping2
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1.State Key Laboratory of High Performance Civil Engineering Materials， Jiangsu Research Institute of Building Science Co.， Ltd.， Nanjing 210008， China;2.School of Materials Science and Engineering， Southeast University， Nanjing 211189， China;3.Guangdong Highway Construction Co.， Ltd.， Guangzhou 510623， China
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| Abstract: |
| The change of particle size of super absorbent polymers （SAP） in different early age extracted pore solutions and the real cement paste environment was observed， then the desorption behavior of SAP in cement paste during early age harden process was analyzed. Results indicate that the change of saturation equilibrium absorption capacity of SAP in different early age extracted pore solutions can not represent the desorption behavior of SAP in the real cement paste environment. Desorption rate of SAP is relatively fast in the early plastic stage after mixing and become prominent during a short period after setting， and then became slowly again at the later harden stage. Water released by SAP in plastic stage reduce the capillary pressure of cement paste， which is benefit to reduce the plastic shrinkage， but consume the ability to inhibit the autogenous shrinkage in harden stage. |
| Key words: super absorbent polymer（SAP） desorption behavior real cement paste environment capillary pressure autogenous deformation |
