There is a growing interest in developing stretchable strain sensors to quantify the large mechanical deformation and strain associated with the activities for a wide range of species. Herein, we constructed elastomeric, healable HIPC rubberlike film by complexation of hydrogen-bond (H-bond) donating poly(acrylic acid) (PAA) and H-bond accepting poly(ethylene oxide) (PEO) (or poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (F108)). All HIPC elastomers prepared from varied PAA/PEO (or PAA/F108) ratios are all healable elastomers with high extensibility (with the highest strain of 1400%). Recovery of all films can automatically occur or be accelerated by externally-added water droplet. The stress and strain healing efficiencies ((ησ and ηε) of the water-assisting healed PAA/F108 blends are as high as 99%. Furthermore, stretchable and healable conductor films were fabricated from the silver nanowire (AgNWs)-printed (Ag-p) and the single-walled carbon nanotube (SWCNT)-blended (SW-b) conductor films, respectively. The healable Ag-p conductor film is ultra-sensitive strain sensor, exhibiting large electric resistance variation when stretched. In contrast, the healable SW-b film is ultra-stable strain sensor with reversible resistance-strain response over 200 stretching-release cycles within a high strain range of 500%. Therefore, this study provides a new and flexible HIPC strategy for the fabrications of stretchable, ultra-sensitive and -stable self-healing electrode materials.
In this study, we proposed a new design strategy to synthesize a highly flexible polymer Jeffamine end-capped with Tannic Acid (TA), then blend with Jeffamine form the ionic interaction between diamino group and catechol group which also can compare with Jeffamine blend with TA the less flexible chain in the mixture, but the interaction was amino terminated and TA terminated, whereas the mechanical property was relatively weak which will limit its property, thus the formation of metal- catechol mono- or bis- coordinate bonds between FeCl3 and TA, both flexible chain of polymer and reversible binding increased together, the malleability of the films was enhanced to a maximum value and consequently results in the well self-healing property of the films. Furthermore, flexible conductor was immersing films from KCl solution. The stretchable, healable swelling conductor can be used as sensor for motion detection and strain sensor that may be applied as flexible electronic device.
In this study, we proposed design strategy to synthesize triblock copolymers having hard poly(acrylic acid) (PAA) blocks and soft poly(ethylene oxide) (PEO) block by atom transfer radical polymerization (ATRP). And dynamic hydrogen bonding blocks were formed by PAA and PEO and the elastomer can be obtained, although the enhancement of covalent bond will exhibit a higher mechanical strength, toughness, but the more PEO chain in the matrix will lead to crystallize, which will decrease its mechanical property. Moreover, the not enough H-bond also limit its self-healing property, thus, we add PAA to enhance the H-bond and it also limit the crystalline of PEO, which will improve the elongation and self-healing property.