Printable, adhesive, and self-healing dry epidermal electrodes based on PEDOT:PSS and polyurethane diol

Abstract

Printable, self-healing, stretchable, and conductive materials have tremendous potential for the fabrication of advanced electronic devices. Poly(3,4-ethylenedioxithiopene) doped with polystyrene sulfonate (PEDOT:PSS) has been the focus of extensive research due to its tunable electrical and mechanical properties. Owing to its solution-processability and self-healing ability, PEDOT:PSS is an excellent candidate for developing printable inks. In this study, we developed printable, stretchable, dry, lightly adhesive, and self-healing materials for biomedical applications. Polyurethane diol (PUD), polyethylene glycol (PEG), and sorbitol were investigated as additives for PEDOT:PSS. In this study, we identified an optimal printable mixture obtained by incorporating PUD into PEDOT:PSS, which improved both the mechanical and electrical properties. Based on our optimization, for the 5% PUD/PEDOT:PSS free-standing films, a conductivity of approximately 30 S/cm, stretchability of 40%, and Young’s modulus of 15 MPa were observed with a light adhesion of 0.03 N/cm. A low resistance change (< 20%) was achieved when the strain was increased to 30%. Excellent electrical stability under cyclic mechanical strain, biocompatibility, and 100% electrical self-healing were also observed. The potential biomedical applications of this mixture were demonstrated by using a printed epidermal electrode on a stretchable silicone substrate. The PUD/PEDOT:PSS electrodes displayed a skin-electrode impedance similar to commercially available electrodes, and successfully captured physiological signals. This study contributes to the development of improved customization and enhanced mechanical durability of soft electronic materials.

A self-healing elastomer with outstanding mechanical properties was designed based on urea bonds

“…Graphene plays the role of an efficient electron-conducting tunnel. 35,47–49 Sensors made of DDPU can be used to monitor human movement. 47 By controlling the graphene content in DDPU, the sensitivity of the sensor can be adjusted.…”

Effect of Aggregation Structure on Capacitive Energy Storage in Conducting Polymer Films

“…These distinctive properties have made PEDOT : PSS a prominent subject of research in the field of flexible supercapacitors, and researchers are actively developing electrically conductive PEDOT : PSS‐based materials with excellent mechanical properties and multifunctionality. Some successful examples, such as the use of various additives such as Triton X‐100, dimethyl sulfoxide and sorbitol, [16–18] or acid and alkali post‐treatment [19] and strain engineering through uniaxial stretching in the form of fibers, [20] have a positive effect on PEDOT : PSS films. While significant progress has been made in improving the electrical conductivity and capacitive performance of PEDOT : PSS‐based electrode materials, few researchers have investigated the effect of the molecular chain spatial order of PEDOT : PSS on the transport of ions and electrons as well as the capacitive performance.…”

Highly Stretchable Self-Adhesive PEDOT:PSS Dry Electrodes for Biopotential Monitoring

“…In addition, a self-adhesive conducting polymer produced from supramolecular solvent SMS and a PVA network covalently cross-linked with glutaraldehyde (GA) doped in PEDOT:PSS shows a low modulus of 56.1–401.9 kPa and an electrical conductivity of 37 S/cm, which can be used in integrated systems for visualization consisting of electroluminescent devices and EMG signals. Nevertheless, multiple network structures will adversely affect the conductivity while enhancing the mechanical properties , of the film, and a low modulus value may cause the film to be damaged during physical movement. − …”