Shang Xiaoyu, Zhan Baojian, Li Jiangshan, Zhong Rui
School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin, 132012, PR China.
Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, PR China.
Sci Rep. 2020 May 20;10(1):8318. doi: 10.1038/s41598-020-65285-6.
Conventional internal curing materials for high-performance cementitious system cannot easily have artificial modifications, such that the curing effect is difficult to control during the process. In this study, a novel microcapsule is proposed for controlled internal curing of cement-based materials. The microcapsules are synthesized by a double emulsion method to form a polymer shell-water core structure. The sensitivity of polymer shell to alkaline environments is used to trigger the release of core water. Thus, water release can be controlled by tailoring the shell thickness and microcapsules sizes by changing the polymer dosage and stirring rate during synthesis. The experimental results indicate that the novel microcapsules can effectively release water for internal curing of a cementitious matrix, which exhibits a high curing efficiency in terms of nearly autogenous shrinkage and increases the compressive strength. The novel microcapsules could be promising internal curing agents to enhance high-performance cement-based materials.
用于高性能胶凝体系的传统内部养护材料不易进行人工改性，因此在过程中养护效果难以控制。在本研究中，提出了一种用于水泥基材料可控内部养护的新型微胶囊。微胶囊通过双乳液法合成，形成聚合物壳-水核结构。利用聚合物壳对碱性环境的敏感性来触发核水的释放。因此，通过在合成过程中改变聚合物用量和搅拌速率来调整壳厚度和微胶囊尺寸，可以控制水的释放。实验结果表明，新型微胶囊能够有效地释放水分用于胶凝基体的内部养护，在几乎自收缩方面表现出高养护效率，并提高了抗压强度。新型微胶囊有望成为增强高性能水泥基材料的内部养护剂。
