The application of self-healing property to cement-based materials promoted a long-term service time in engineering. In this study, dimethyl thio-toluene diamine (DMTDA) microcapsules were synthesized successfully through melting-dispersion-condensation techniques, and enabled crack closure thus recovering the mechanical property. The as-fabricated DMTDA microcapsules showed a core-shell structure and well-dispersed properties with a tailorable core fraction and diameter, (e.g., a diameter of 312.7 ± 97.6 μm and a shell thickness of 15.2 ± 2.6 μm under agitation rate of 300 RPM). It was found that DMTDA microcapsules had a high core fraction and good thermal stability. The introduction of microcapsules decreased the flowability of cement paste but remained integral structures during the mechanical agitation. The increase of microcapsule concentrations led to a significant drop in porosity but a slight decrease in compressive strength of cement paste. Most importantly, the addition of DMTDA microcapsules and isocyanates microcapsules in the cement paste could repair the early hydration cracks with a size less than 100 μm, thereafter achieving a satisfying recovery of the compressive strength.

自愈性在水泥基材料中的应用，促进了工程的长期使用。在本研究中，通过熔融-分散-缩合技术成功合成了二甲基硫代甲苯二胺（DMTDA）微胶囊，并实现了裂纹闭合，从而恢复了机械性能。制造的 DMTDA 微胶囊显示出核壳结构和良好分散的特性，具有可定制的核分数和直径（例如，在 300 RPM 的搅拌速率下，直径为 312.7 ± 97.6 μm，壳厚度为 15.2 ± 2.6 μm ）。发现 DMTDA 微胶囊具有高核心分数和良好的热稳定性。微胶囊的引入降低了水泥浆的流动性，但在机械搅拌过程中保持整体结构。微胶囊浓度的增加导致孔隙率显着下降，但水泥浆体的抗压强度略有下降。最重要的是，在水泥浆中加入DMTDA微胶囊和异氰酸酯微胶囊可以修复早期小于100μm的水化裂缝，之后达到令人满意的抗压强度恢复。