A Biologically Muscle‐Inspired Polyurethane with Super‐Tough, Thermal Reparable and Self‐Healing Capabilities for Stretchable Electronics

Abstract

Polymeric elastomers play an increasingly important role in the development of stretchable electronics. A highly demanded elastic matrix is preferred to own not only excellent mechanical properties, but also additional features like high toughness and fast self‐healing. Here, a polyurethane (DA‐PU) is synthesized with donor and acceptor groups alternately distributed along the main chain to achieve both intra‐chain and inter‐chain donor‐acceptor self‐assembly, which endow the polyurethane with toughness, self‐healing, and, more interestingly, thermal repair, like human muscle. In detail, DA‐PU exhibits an amazing mechanical performance with elongation at break of 1900% and toughness of 175.9 MJ m−3. Moreover, it shows remarkable anti‐fatigue and anti‐stress relaxation properties as manifested by cyclic tensile and stress relaxation tests, respectively. Even in case of large strain deformation or long‐time stretch, it can almost completely restore to original length by thermal repair at 60 °C in 60 s. The self‐healing speed of DA‐PU is gradually enhanced with the increasing temperature, and can be 1.0–6.15 µm min−1 from 60 to 80 °C. At last, a stretchable and self‐healable capacitive sensor is constructed and evaluated to prove that DA‐PU matrix can ensure the stability of electronics even after critical deformation and cut off.

Skin-like hydrogel devices for wearable sensing, soft robotics and beyond

“…Importantly, the skin contains the largest amount of sensing receptors to perceive various environmental stimuli that humans encounter, such as pressure, strain, humidity, temperature, and pain ( Figure 1 A). To date, tremendous skin-inspired flexible and stretchable devices have been developed based on our understanding of the human skin’s sensing functions ( Benight et al., 2013 ; Cheng et al., 2019 ; Kim et al, 2011a , 2011b , 2016a ; Lei and Wu, 2018 ; Liang et al., 2013 ; Lipomi et al., 2011 ; Oh et al., 2016 ; Pelrine et al., 2000 ; Sekitani et al., 2008 , 2009 ; Sun et al, 2006 , 2014 ; Ying et al., 2020a , 2020c , 2021b , 2021c ; Yu et al., 2020d ; Zang et al., 2013 ). These advances have revolutionized wearable electronics and other related fields.…”

Flexible and Stretchable Bioelectronics

“…This further proves that PU is another organic material with multiple applications for flexible and stretchable bioelectronics. Elastomeric PU has even been advanced to be self-healing, with an elongation at break of 1900% [ 52 ]. Like PDMS, PU can be used as a base insulator to layer conductive tracts upon it.…”

Light-driven self-healing polyurethane based on PDA@Ag nanoparticles with improved mechanical and antibacterial properties

“…[1][2][3][4] With the escalation of hygiene requirements, antibacterial PU coatings have attracted significant attention from both academic and industrial societies. [5][6][7] As known, silverbased nano-materials have broad-spectrum antibacterial properties against an extensive range of microorganisms. [8][9][10] Among them, AgNPs used in PU materials furnish PU/silver nanocomposites with antibacterial properties.…”