A tri-responsive and fast self-healing organogel with stretchability based on multiple dynamic covalent bonds

Smart self-healing materials have attracted much attention due to their promising applications in biological and medical fields. Here, a tri-responsive and fast self-healing organogel based on a boronate ester bond, an acylhydrazone bond and a disulfide bond was prepared from polyvinyl alcohol (PVA), 4-formylphenylboronic acid (FPBA), and 3,3 '-dithiobis (propionohydrazide) (DPH). PVA was selected as a gel skeleton to improve the mechanical property of the organogel. A tensile test indicated that the obtained organogel is highly stretchable. Due to the dynamic nature of reversible covalent chemistry, the organogel can respond to pH, glucose and redox to undergo gel-sol phase transition. Microscopy observation and tensile tests further indicate that the organogel can self-repair without external stimuli.