Stretchable, self-healing and adhesive sodium alginate-based composite hydrogels as wearable strain sensors for expansion-contraction motion monitoring.

Developing multifunctional hydrogels with stretchability, self-healing ability, adhesiveness, and conductivity into flexible strain sensors for human motion and health monitoring has attracted great attention and is highly desired. However, the present motion detectors mainly focus on stretching, bending, and twisting of different body parts while the expansion-contraction motion has been rarely investigated. In this study, along with carbon nanotubes (CNTs) as conductive components, sodium alginate (Alg) modified with 3-aminophenylboronic acid (PBA) and dopamine (DA) were synthesized and employed as precursors to prepare a multifunctional Alg-CNT hydrogel.