Highly Stretchable, Adhesive, and Self‐Healing Silk Fibroin‐Dopted Hydrogels for Wearable Sensors

Abstract

In recent years, the preparations of flexible electronic devices have attracted great attention. Here, a simple one-pot method of thermal polymerization is introduced to fabricate silk fibroin-dopted hydrogels (SFHs), which are both chemically and physically cross-linked by acrylamide (AM), acrylic acid (AA), and silk fibroin (SF). The addition of SF can effectively enhance the mechanical property of the SFH 12% by 59% compared with SFH 0% . Taking the advantage of its wide working range of stress (about 0.455-568.9 kPa), the SFH can work as a resistance-type pressure sensor to monitor different human motions. What is more, the excellent adhesion, about 75.17 N m −1 of SFH 46% enables it to fit tightly to other objects during the testing, which significantly reduces the loss of small signals due to poor fit. In addition, the SFH demonstrates excellent self-healing property without requiring external excitation and a sensitive temperature response in the range of −10 to 60°C. The SFH is expected to be applied in the field of electronic skin, soft robots, and other flexible electronic products as well as speech recognition.

Self-Healing, Self-Adhesive Silk Fibroin Conductive Hydrogel as a Flexible Strain Sensor

“…2 Then, the mechanical signal changes caused by the human body's physiological reaction or skin deformation during exercise are converted into electrical signals such as capacitance or resistance so as to realize real-time monitoring. 3,4 However, the traditional wearable electronic sensing devices are often rigid and brittle. The conformal contact ability with skin is poor.…”

“…The design of traditional wearable electronic sensing devices mostly combines conductive materials with flexible substrates and attaches them to the surface of the human body by external aids . Then, the mechanical signal changes caused by the human body’s physiological reaction or skin deformation during exercise are converted into electrical signals such as capacitance or resistance so as to realize real-time monitoring. , However, the traditional wearable electronic sensing devices are often rigid and brittle. The conformal contact ability with skin is poor.…”

Ionic liquid functionalized injectable and conductive hyaluronic acid hydrogels for the efficient repair of diabetic wounds under electrical stimulation

“…Materials with mechanical properties that are similar to those of the skin are beneficial for wound repair because they can maintain their integrity, and also facilitate satisfactory adhesion when the skin tissue is deformed under external force. 33,34 The tensile test results are shown in Fig. 3a.…”

Designable Integration of Silicide Nanowire Springs as Ultra‐Compact and Stretchable Electronic Interconnections

“…Stretchable electronics with compliant mechanical deformability and electrical reliability [ 1 ] have been the focus of intense research over the past decades, which are indispensable features required in the fields of medical devices, [ 2 ] displays, [ 3,4 ] sensors, [ 5–10 ] wearable devices, [ 11–13 ] memory, [ 14,15 ] and electronic skins. [ 16–18 ] While the active electronic logic, sensor or light emission units can be safely constructed and protected upon discrete rigid‐islands, distributed on the soft polymer (such as, PDMS) substrate as depicted in Figure a, the conductive interconnections among the islands must be highly elastic and robust to sustain or dissipate large stretching strain.…”