Transparent High‐Performance Supramolecular Plastics Operating in All‐Weather Environments

Abstract

Supramolecular plastics (SMPs) can be made mechanically robust, repairable, and recyclable, rendering themselves promising alternatives to their conventional predecessors to address environmental concerns. However, dense accumulations of noncovalent bonds generally lead to mechanical brittleness as well as intolerance toward heat and moisture. To resolve this issue, a simple strategy of preparing high-performance SMP by constructing highly dense, but irregular hydrogen-bond networks with hierarchical structures is proposed. The resultant SMP exhibits an outstanding combination of good comprehensive mechanical properties (high stiffness, strength, and toughness with ductile failure when fracturing), excellent dynamic behaviors (repairability and recyclability), and high tolerances toward moisture and high temperatures (as high as 90 °C). Additionally, the SMP also shows a high dielectric constant, exhibiting great potential for applications such as healable flexible touch screens and energy storage. Last, through structure characterizations and molecular dynamic simulation, this study provides a fundamental insight into the mechanism behind such high-performances from nano-to micro-scales, which is expected to inspire the design of a wide range of other SMPs that use different chemistries.

Spatiotemporally Responsive Hydrogel Dressing with Self‐Adaptive Antibacterial Activity and Cell Compatibility for Wound Sealing and Healing

“…Note to worthy, the hydrogels saw a decrease in Young's modulus from 3.6 to 1.7 kPa after the introduction of HAp, probably because of the inhibited polymerization of QAS or weakened hydrogen bonding interaction of HAp and QAS. [36][37][38][39] Further increase in HAp content (e.g., 0.6%) would lead to a higher Young's modulus 6.7 kPa but with significant losses of the tensile strength (12.8 kPa) and elongation at break (255.4%) due to the restricted chain movement in the case of a high crosslinking degree. Overall, the composite hydrogel had a low Young's modulus with high stress, elongation at break and toughness, making it a great candidate to fabricate soft, durable, and robust wound dressing that could not only conform to biological tissue but tolerate large deformation and body motion.…”

Electrically Functional Self‐Healing Polymers: Design, Assessment, and Progress

“…In addition, this polymer with layered hydrogen bonds has strong environmental stability, exhibiting similar mechanical and thermodynamic properties in a variety of solvents over a wide temperature range of 25 °C to 90 °C (Figure 3c). [ 31 ] To solve the problem of poor toughness for flexible self‐healing polymers, our group designed a self‐healing polymer with high toughness, inspired by the microstructure of smooth muscle in living organisms. [ 32 ] In detail, spindle‐like liquid metal particles with core–shell structure are implanted into soft self‐healing polyurea matrix (Figure 3d).…”

“…Inset in panel (c) shows the comparison of the fracture energy, elongation at break, and fracture stress. Reproduced with permission [31]. Copyright 2023, Wiley-VCH GmbH.…”

Poly(urea-urethane) Elastomers Showing Autonomous Healing at Room Temperature

“…53 To reduce the temperature of the healing process, poly(ureaether) films with a high tensile strength (62 MPa) and excellent transparency were prepared by a polyaddition reaction. 54 Scratches on the films were healed in the presence of a vapor of isopropyl alcohol for 30 min at 60 °C. Besides, a glassy polyurethane with loosely packed hydrogen bonds was synthesized to prepare materials with a fast healing process.…”

“…Polyacrylate containing a reversible polymer network (glass transition temperature = 42 °C) was synthesized by linear copolymers presenting furan side chains with aliphatic bismaleimides through a Diels–Alder reaction. 40 μm wide and 2 μm deep scratches were healed after heating at 150 °C for 90 min To reduce the temperature of the healing process, poly­(urea-ether) films with a high tensile strength (62 MPa) and excellent transparency were prepared by a polyaddition reaction . Scratches on the films were healed in the presence of a vapor of isopropyl alcohol for 30 min at 60 °C.…”