异氰酸酯自修复微胶囊水泥基材料的制备与性能研究

Preparation and properties of isocyanate self-healing microcapsule cement-based material

自修复微胶囊水泥基材料能够自发修复基体内的微裂纹。采用界面聚合法制备异氰酸酯微胶囊,利用蒙脱土改性壁材,研究掺自修复微胶囊的自愈合砂浆强度变化及自修复效果。通过工艺参数优化,确定最佳合成条件为:反应时间2 h、温度50℃、壁材3 g、芯材13.5 g、蒙脱土用量1%,此时芯材含量为61.5%。微观及宏观分析发现,微胶囊的耐碱性良好,可以与水泥基材料相容;微胶囊最佳掺量为4%,此时自愈合砂浆试件的抗压强度恢复率为117.38%。

Self-healing microcapsule cement-based materials can repair microcracks in the matrix spontaneously.Isocyanate microcapsules were prepared by interfacial polymerization method,and montmorillonite was used to modify the wall material to study the strength change and self-healing effect of self-healing mortar mixed with self-healing microcapsules.By optimizing the process parameters,the optimal synthesis conditions were determined as follows:reaction time 2 hours,temperature 50℃,wall material 3 g,core material 13.5 g and montmorillonite content 1%.At this time,the core material content was 61.5%.Micro and macro analysis results show that the microcapsules have good alkaline resistance and can be compatible with cement-based materials.The optimal microcapsule content is 4%,the compressive strength recovery rate of the self-healing mortar specimen is 117.38%.