Recent developments: self-healing polymers based on quadruple hydrogen bonds

Abstract

The microcrack of materials was inevitable in the process of transportation, storage and utilization, which may cause functional failure and resources waste. Inspired by nature, self-healing polymers have attracted significant attention owing to widespread applications in wearable electronics, cartilage replacement, coatings and elastomer. Compared with extrinsic healing, intrinsically healable polymers offer multiple self-healing by supramolecular reversible interactions, such as host-guest interactions, π-π stacking, ionic interactions and hydrogen-bonding. Self-healing polymers based on quadruple hydrogen bonds have been extensively investigated due to its high thermodynamic stability and rapid kinetic reversibility, and have been well developed for the past two decades. In this paper, the strategies and designs of self-repairing polymers based on quadruple hydrogen bond were classified and summarized, including main-chain self-healing polymers, side-chain self-healing polymers and supramolecular self-healing polymers. It is expected that quadruple hydrogen bonding can be construct more robust, highly tough, multi-stimuli-responsive, and fast self-healing supramolecular polymer, and is potential to be applied to numerous civilian and military fields in the future.

Urea-Functionalized Heterocycles: Structure, Hydrogen Bonding and Applications

“…Although the DDAA pattern was shown to be the favorable motif in obtaining stable homodimers in most cases, there are also some examples when complexation takes place via the formation of a DADA array. Interestingly, in contrast to other pyrimidine-4,6-diones (10,14,15), the 1-naphthyl derivative 16 was shown to form a dimeric structure of the DADA tautomers [41]. This assumption was supported in solution as well as in solid state by NMR measurements and X-ray crystallography, respectively.…”

“…The non-covalent interactions can be useful in the design of elastomers, selfhealing polymers, bioactive materials and molecular catalysts. Although there are some examples of supramolecular polymers of ureas constructed using triply [96] or sextuply H-bonded units [97], the most common motifs are those capable of forming quadruple H-bonds [15,98,99].…”

“…This area seems to be the most rapidly growing field of applications. Accordingly, supramolecular polymers based on quadruple H-bonds have been reviewed recently [15,16]. Also, a great number of reviews, summarizing the development, properties and applications of supramolecular polymers formed via different types of secondary interactions, including H-bonded arrays, have been reported.…”

“…Because of the growing number of publications in these areas, the examples are taken from the past 10 years. Also, due to the several reviews available on the use of supramolecular polymers [15][16][17][18][19][20][21][22], just some examples will be presented to highlight the main areas of applications, without intending to be comprehensive. With the use of molecules with two or more H-bonding arrays, supramolecular structures with different architectures and tunable properties can be constructed.…”

Self-healable, super Li-ion conductive, and flexible quasi-solid electrolyte for long-term safe lithium sulfur batteries

“…Due to the hydrogen bonded networks enabled by the PU molecules, the PAES-g-(PU/2PEG) membrane can dissipate the mechanical energy under an external force to recover their original structures with high self-healing efficiency. 70 Graing of poly(1,2-bis(ureido ethylene methacrylate ethyl) disulde) (PUS) was also conducted to more reduce the self-healing time (s sh ) via disulde metathesis (S-S) with low reaction activation energy in addition to hydrogen bondings. 71,72 The effect of PU and PUS on the self-healing efficiency (E sh ) and s sh was investigated and compared in this work.…”