Facile fabrication of self-healing carboxymethyl cellulose hydrogels

As a material derived from cellulose, which is abundant in nature, carboxymethyl cellulose (CMC) has been used as an ingredient to synthesize hydrogels for various applications. The introduction of self-healing properties in CMC hydrogels will expand their service life and scope of application. We report a facile way to fabricate CMC hydrogels with self-healing behaviour. The self-healing CMC hydrogel is achieved by acidifying the CMC paste in citric acid solution. The CMC hydrogel can autonomously self-heal without any external stimulus under ambient temperature, and the healed hydrogels can bear the stretching as demonstrated by macroscopic observation. The hydrogel with ∼2.5   MPa compressive strength exhibits ∼80% of healing efficiency. With these superior properties, the developed CMC hydrogel holds great potential for applications in biomedical and industry fields.