Ultrastable, Superrobust, and Recyclable Supramolecular Polymer Networks

Abstract

Supramolecular polymer networks (SPNs), crosslinked by noncovalent bonds, have emerged as reorganizable and recyclable polymeric materials with unique functionality. However, poor stability is an imperative challenge faced by SPNs, because SPNs are susceptible to heat, water, and/or solvents due to the dynamic and reversible nature of noncovalent bonds. Herein, the design of a noncovalent cooperative network (NCoN) to simultaneously stabilize and reinforce SPNs is reported, resulting in an ultrastable, superrobust, and recyclable SPN. The NCoN is constructed by multiplying the H‐bonding sites and tuning the conformation/geometry of the H‐bonding segment to optimize the multivalence cooperativity of H‐bonds. The rationally designed H‐bonding segment with high conformational compliance favors the formation of tightly packed H‐bond arrays comprising higher‐density and stronger H‐bonds. Consequently, the H‐bonded crosslinks in the NCoN display a covalent crosslinking effect but retain on‐demand dynamics and reversibility. The resultant ultrastable SPN not only displays remarkable resistance to heat up to 120 °C, water soaking, and a broad spectrum of solvents, but also possesses a superhigh true stress at break (1.1 GPa) and an ultrahigh toughness (406 MJ m‐3). Despite the covalent‐network‐like stability, the SPN is recyclable through activating its reversibility in a high‐polarity solvent heated to a threshold temperature.

Synthesis of Novel Nonisocyanate Poly(imide-urea)s from CO2-based Polyureas

“…The crystallinity of PUas stems from their well-organized linear structure and ordered hydrogen bonds. Theoretically, the hydrogen-bonding network in PUa and PIU should be quite similar, as the hydrogen bonds are stemmed from the urea units of PUa in which bidentate hydrogen bonds with a higher degree in order can be formed, owing to the presence of flexible aliphatic spacers (TTD) that endowed the polymeric chains with a higher conformational compliance . In contrast, in PIUs, the hydrogen bonds were dispersed and less ordered due to the stiffness and steric hindrance imposed by the aromatic polyimide spacer on the polymeric chains.…”

Cage-by-cage supramolecular polymerization via panel-decorated triphenylphosphine organic cage

“…hydrogenbonding, metal-coordination and π-π stacking), rather than the common covalent linkages [1,2]. These weak interactions can undergo dynamic recombination and dissociation under appropriate conditions, endowing supramolecular polymers with favorable reversibility, responsivity and adaptability, distinct from their covalent counterparts [3][4][5]. Over the past decades, this filed has witnessed the blooming development and various noncovalent polymeric structures have been * Author to whom any correspondence should be addressed.…”

Enabling Supramolecular Phase Change Materials with High Latent Heat Ability and Recyclability

“…Supramolecular polymers consist of interconnected repeating units through reversible and directional noncovalent bonding interactions. − Supramolecular polymers are mainly obtained by self-assembly of building blocks, which includes both noncovalent polymerization of covalent monomers and noncovalent cross-linking of linear polymers, showing good designability. − In supramolecular polymers, monomer molecules and polymer molecules are connected through a large number of hydrogen bonds, ionic bonds, ligand bonds, or host–guest interactions to maintain the stability of the material structure and properties. , In addition, supramolecular polymers have good reprocessing properties due to the absence of chemical cross-linking structures in them. , Introducing supramolecular polymers into PCMs can both realize the encapsulation of PEG and solve the leakage problem, as well as eliminate the adverse effects of chemical cross-linking on the destruction of PEG crystallization . And it also makes the PCMs have reprocessing properties.…”