Double-network PVA/gelatin/borax hydrogels with self-healing, strength, stretchable, stable, and transparent properties

Hydrogels have displayed great potential applications in biological intelligent devices, tissue engineering and electronic wearable fields. As the two most important factors limiting the application of hydrogels, strength and self-healing ability have always been the focus of research, but the incompatibility between them has not been resolved. It is worth noting that double-network structure and the introduction of reversible bonds show great promise as a feasible scheme to solve the above problems. Herein, the PVA/G/B double-network hydrogels were developed by a simple synthesis process and exhibited excellent properties, including strong tensile strength (similar to 787 kPa), high elongation at break (similar to 200%), excellent self-healing properties (healing efficiency exceeds 93%), good dimensional stability and transparency. This study provides an effective method for designing hydrogels with high strength, stretchability, stability, transparency and excellent self-healing properties based on the gelatin reinforcing strategy.