Notch-Insensitive, Ultrastretchable, Efficient Self-Healing Supramolecular Polymers Constructed from Multiphase Active Hydrogen Bonds for Electronic Applications

Abstract

Self-healing polymers with microphase-separated structure are plagued with inferior self-healing efficiency at room temperature due to a lack of dynamic interactions in hard domains. Herein, we describe a novel strategy of multiphase active hydrogen bonds (H-bonds), toward realizing fast and efficient self-healing at room temperature, even under harsh conditions. The core conception is to incorporate thiourea moieties into microphase-separated polyurea network to form multistrength H-bonds, which destroy the crystallization of hard domains and, at the same time, insert the dynamic reversible H-bonds in both hard and soft segments, accounting for the surprisingly self-healing performances. The synthesized polymeric material, poly­(dimethylsiloxane)–4,4′-methylenebis­(phenyl isocyanate)–1,1′-thiocarbonyldiimidazole, completely recovers all of the mechanical properties within 4 h at room temperature after rupture. Significantly, self-healing process can also take place at low temperature (restoration with an 85% efficiency in 48 h at −20 °C) or in the water (restoration with a 95% efficiency in 4 h). Depending on the cleavage/reformation of multiphase H-bonds, the material exhibits unprecedented ultrastrechability and notch-insensitiveness. It can be stretched up to 31 500% without fracture and reach a notch-insensitive stretching of up to 18 000%. These exceptional characteristics inspired us to fabricate highly stretchable self-healable underwater conductor and protective self-healing film for suppressing shuttling of polysulfides and preventing crack propagation in S cathode, which provide the pathway for applications in underwater electronic devices or advanced Li–S batteries.

A Fast Room‐Temperature Self‐Healing Glassy Polyurethane

“…Figure S5 in the Supporting Information shows the 2D-FTIR spectra of GPU ranging from 1800 to 1000 cm À1 and 3400 to 3200 cm À1 ,w here the absorption peaks at 1705, 3323, 1238, and 1101 are attributed to vC = O, vN À H, vC À O, and vC À O À C, respectively.T hree correlation cross peaks at F(1705, 3323), F(1238, 3323), and F(1101, 3323) emerge in the synchronous 2D-FTIR spectra (Supporting Information, Figure S5a), and do not appear in the corresponding asynchronous 2D-FTIR spectra (Supporting Information, Figure S5b), confirming the existence of intramolecular/intermolecular hydrogen bonding derived from urethane and ether moieties. [9] Meanwhile, 1 HNMR experiments exhibit ad istinctive shift of the NÀHp roton towards alow field with increasing concentration (Figure 1d), in agreement with 2D-FTIR, providing strong evidence for the multiple hydrogen bonding modes. [10] Moreover,because Penta-EG possesses as hort chain length, the density of hydrogen bonds in the polymer network is very high, which results in ah igh T g of GPU.T his value,d etermined by differential scanning calorimetry (DSC), is 36.8 8 8C ( Figure 1e), indicating that it is ag lassy polymer at ambient temperature.M eanwhile,t here are no endothermic/exothermic peaks in the DSC curve from À80 to 200 8 8C, demonstrating the amorphous structure of GPU,w hich was further confirmed by X-ray diffraction (XRD) (Supporting Information, Figure S6).…”

Strong Chemical Interaction between Lithium Polysulfides and Flame‐Retardant Polyphosphazene for Lithium–Sulfur Batteries with Enhanced Safety and Electrochemical Performance

“…The three samples reveal a wide absorption in the region between 250 and 300 nm, where the peaks located about 264 and 283 nm can be imputed to S 6 2− species (Figure 2a). [ 41 ] Compared with untreated Li 2 S 6 solution, the peak intensity of Li 2 S 6 solution mixed with HG‐CCP reduces mildly, but for PPZ‐HG‐CCP, the absorption peak intensity of Li 2 S 6 solution decreases significantly, demonstrating the strong affinity of PPZ‐HG‐CCP toward LiPS, and thus preventing shuttle effect of LiPS. When the 0.1 m LiPS solution was added to the PPZ powder (100 mg), it can be clearly seen that the color of the solution quickly becomes colorless (Video S1, Supporting Information), indicating that the strong affinity of PPZ‐HG‐CCP toward LiPS is mainly ascribed to the interaction between PPZ and LiPS.…”

Development of a Strong, Recyclable Poly(dimethylsiloxane) Elastomer with Autonomic Self‐Healing Capabilities and Fluorescence Response Properties at Room Temperature

“…This challenge, that is, realizing the synchronous optimization of mechanical properties, self-remediation, and recyclability of materials, has not yet been solved. In recent years, researchers have developed multiple dynamic bond collaborative strategies [43][44][45][46] that combine two types of dynamic bonds (for example, combining metalligand interactions with hydrogen-bonding interactions [47] or disulfide metathesis with hydrogen-bonding interactions [48] ) to improve the robustness or stretching performance of self-healing materials. However, state-of-the-art self-healing materials are still not good enough because most materials produced using current design strategies are typically either tough but brittle or stretchable but weak.…”