Pickering Emulsion-Based 3D Printing for Efficient Vascular Self-Healing in Cementitious Materials. (2026-04)¶

To address the crack healing and durability enhancement of concrete, a novel and pragmatic vascular self-healing approach has been developed, and a quantitative characterization of vascular healing efficiency has been presented. A biocompatible Pickering emulsion containing no surfactant or other organic modifiers, consisting of natural montmorillonite co-stabilized with carboxymethyl cellulose on methyl palmitate, is developed as a 3D printing ink to construct hollow pipelines in cement in situ, which is characterized by means of Fourier transform infrared spectroscopy (FT-IR), zeta potential, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and rheological property measurement, showing that it can be long-term stored stably, 3D printed smoothly, self-supporting steadily in cement and self-dissolving forming hollow pipeline following cement curing. The manufacture of pipelines in various diameters is facilitated by variable control settings in 3D printing. X-ray computed tomography is used to characterize the internal pipelines, revealing excellent connectivity and coherence in their architecture. Bending and compression tests indicate that larger pipeline diameters exhibit better strength recovery at lower pumping pressures. Watertightness tests demonstrate the pipeline's remarkable crack-healing capability across cement specimens of varying widths, achieving nearly complete seals for cracks 100 μm and 200 μm wide. This is attributable to the pipeline's outstanding transport performance. SEM and X-CT analyses confirm excellent adhesion of the polyurethane. Vascular self-healing in cementitious materials with Pickering emulsion-based 3D printing provides outstanding crack healing capability and versatile construction freedom.