Rapidly self-healing, magnetically controllable, stretchable, smart, moldable nanoparticle composite gel

Abstract

Rational design of a magnetic and fast self-healing gel is significant in the field of shape construction. Magnetic gels with rapid self-healing ability constructed using nanoparticles and dynamic chemical bonds have so far been elusive. Here, an ultrafast self-healing magnetic gel based on thioctic acid (TA), ferric chloride (FeCl₃) and ferric oxide (Fe₃O₄) has been successfully synthesized. The reversible interactions of the S–S bond, hydrogen bond and iron(III)–carboxylate coordinate bonds endow a 100% self-healing efficiency for the magnetic gel after healing in air for only 10 min, and a saturation magnetization of the gel of 0.27 emu g⁻¹ can be achieved. The intelligent in situ healing ability of the as-obtained magnetic gel guarantees the same function and shape as the original gel. This combination of high-efficiency repaired performance and magnetic properties can broaden the range of applications for shape construction through the “building blocks” consisting of magnetic gels.