High-Strength Thermally Activated Shape-Adaptive Plugging Hydrogels with Plastic Semicrystalline Metallosupramolecular Polymer Networks

Plugging materials are employed to repair holes or cracks in pipes, vessels, other equipment, or even formations. Traditional packing tape or sealant could seal only small cracks and leaks. Epoxy resins and polyurethane foams are appropriate for sealing relatively large apertures. However, their application is limited by a long curing time or low mechanical performance. Herein, we report thermally activated shape-adaptive plugging materials based on shape-memory hydrogels with high strength and deformation capacity. Owing to the stiff hydrophobic crystalline side segments in the hydrogel network, the shape-memory hydrogel showed high mechanical performances with a compressive strength of 17.57 MPa and toughness of 2760 kJ m–3. Upon immersion in Fe3+ solution, the integration of these two orthogonal supramolecular interactions bestows the hydrogel with high-strength mechanical properties and a distinctive dual-programmed shape-memory performance. Importantly, the excellent shape-memory properties can allow the hydrogel to exhibit a distinctive shape-adaptive plugging behavior. When activated, the flaky intelligent hydrogel expands into a granular shape, allowing them to adaptively match fracture apertures in the leakage zone within a range of 2 to 4 mm, which result in high plugging efficiency and high plugging strength. Therefore, this intelligent, adaptive plugging based on high-strength shape-memory hydrogels could be a prominent candidate for a generation of plugging materials that can be applied in the oil field, waste gas or oil pipeline repairs, and various other plugging scenarios.