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When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition. [ABSTRACT FROM AUTHOR]

Self‐assembly of chromophoric systems is a prerequisite to create well‐ordered, processable nanomaterials with multiple functionalities. In the past two decades, the field of functional organic materials has primarily focused on systems featuring only one type of dye/π‐conjugated unit. Consequently, many reports with mechanistic insights on the self‐assembly of the dyes featuring different molecular packing have been reported. Subsequently, we have witnessed several attempts to organize the multi‐chromophoric systems in solution and solid‐state via different approaches using self‐assembly as a tool. Incorporation of more than one dye is important in creating materials with tuneable optoelectronic properties. Consequently, self‐assembly of more than one chromophoric systems have been investigated to some extent. This review aims to discuss the self‐assembled materials derived from discrete π‐conjugated systems comprising more than one dye units connected through covalent bonding (multi‐chromophoric systems). Molecular design of various multi‐chromophoric systems leading to the formation of crystals, liquid crystals and supramolecular polymers have been correlated with corresponding properties. We envisage that classification of self‐assembled multi‐chromophoric systems, with a note on tuneable optoelectronic properties, can provide a deeper understanding on the molecular design strategies, which is important in the fabrication of functional organic materials with optimum performances. [ABSTRACT FROM AUTHOR]

A novel fluorescent supramolecular polymer (named N3T) has been synthesized resoundingly, which can effectively identify trace amounts of Pd2+ in solution, and then a self-assembled supramolecular catalyst catalyst N3T-Pd was obtained. The N3T-Pd with spherical structure could be used for C–C coupling reactions in an eco-friendly aqueous medium. The catalyst was characterized by NMR, FT-IR, XPS, SEM and fluorescence spectra. The N3T-Pd has prominent stability and recyclability without any decrease of catalytic activity after least five cycles. Notably, the reaction degree of Pd2+ with the supramolecular polymer can be conformed by the fluorescence intensity of the supramolecular polymer. With that, the N3T detection limit (LOD) of Pd2+ was measured by fluorescent titration. Surprisingly, N3T can ultrasensitive detection of Pd2+, the limit of detection was 1.9 × 10−7 M. The self-assembly supramolecular palladium catalyst N3T-Pd has been developed as a novel and efficient catalyst for ligand-free C–C cross-coupling reactions in aqueous at room temperature. [ABSTRACT FROM AUTHOR]

Abstract The synthesis of signal-amplifying chemosensors induced by various triggers is a major challenge for multidisciplinary sciences. In this study, a signal-amplification system that was flexibly manipulated by a dynamic allosteric effector (trigger) was developed. Herein, the focus was on using the behavior of supramolecular polymerization to control the degree of polymerization by changing the concentration of a functional monomer. It was assumed that this control was facilitated by a gradually changing/dynamic allosteric effector. A curved-π buckybowl sumanene and a sumanene-based chemosensor (SC) were employed as the allosteric effector and the molecular binder, respectively. The hetero-supramolecular polymer, (SC·(sumanene)n), facilitated the manipulation of the degree of signal-amplification; this was accomplished by changing the sumanene monomer concentration, which resulted in up to a 62.5-fold amplification of a steroid. The current results and the concept proposed herein provide an alternate method to conventional chemosensors and signal-amplification systems.

The synthesis of signal-amplifying chemosensors induced by various triggers is a major challenge for multidisciplinary sciences. In this study, a signal-amplification system that was flexibly manipulated by a dynamic allosteric effector (trigger) was developed. Herein, the focus was on using the behavior of supramolecular polymerization to control the degree of polymerization by changing the concentration of a functional monomer. It was assumed that this control was facilitated by a gradually changing/dynamic allosteric effector. A curved-π buckybowl sumanene and a sumanene-based chemosensor (SC) were employed as the allosteric effector and the molecular binder, respectively. The hetero-supramolecular polymer, (SC·(sumanene)n), facilitated the manipulation of the degree of signal-amplification; this was accomplished by changing the sumanene monomer concentration, which resulted in up to a 62.5-fold amplification of a steroid. The current results and the concept proposed herein provide an alternate method to conventional chemosensors and signal-amplification systems. [ABSTRACT FROM AUTHOR]

Supramolecular polymers, in which monomers are assembled via intermolecular interactions, have been extensively studied. The fusion of supramolecular polymers with conventional polymers has attracted the attention of many researchers. In this review article, the recent progress in the construction of supramolecular star polymers, including regular star polymers and miktoarm star polymers, is discussed. The initial sections briefly provide an overview of the conventional classification and synthesis methods for star polymers. Coordination‐driven self‐assembly was investigated for the supramolecular synthesis of star polymers. Star polymers with multiple polymer chains radiating from metal‐organic polyhedra (MOPs) have also been described. Particular focus has been placed on the synthesis of star polymers featuring supramolecular cores formed through hydrogen‐bonding‐directed self‐assembly. After describing the synthesis of star polymers based on host‐guest complexes, the construction of miktoarm star polymers based on the molecular recognition of coordination capsules is detailed. [ABSTRACT FROM AUTHOR]

Chemical modifications of enzymes excel in the realm of enzyme engineering due to its directness, robustness, and efficiency; however, challenges persist in devising versatile and effective strategies. In this study, we introduce a supramolecular modification methodology that amalgamates a supramolecular polymer with Candida antarctica lipase B (CalB) to create supramolecular enzymes (SupEnzyme). This approach features the straightforward preparation of a supramolecular amphiphilic polymer (β‐CD@SMA), which was subsequently conjugated to the enzyme, resulting in a SupEnzyme capable of self‐assembly into supramolecular nanoparticles. The resulting SupEnzyme nanoparticles can form micron‐scale supramolecular aggregates through supramolecular and electrostatic interactions with guest entities, thus enhancing catalyst recycling. Remarkably, these aggregates maintain 80 % activity after seven cycles, outperforming Novozym 435. Additionally, they can effectively initiate photobiocatalytic cascade reactions using guest photocatalysts. As a consequence, our SupEnzyme methodology exhibits noteworthy adaptability in enzyme modification, presenting a versatile platform for various polymer, enzyme, and biocompatible catalyst pairings, with potential applications in the fields of chemistry and biology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coordination of four metal ions with the chelator APP and functionalized carbon nanotubes leads to supramolecular polymers as electrode material. • MWCNT-APP-Fe integrates the functions of each component in supramolecular polymer. • Dual energy storage mechanism boosters the high capacity and rate capability for MWCNT-APP-Fe-based supercapacitor. In this paper, we prepared the supramolecular polymers (MWCNT-APP-s) with a dual energy storage mechanism as the electrode materials by the coordination of four transition metal ions with the small molecule chelator (APP) and functionalized carbon nanotubes, respectively. Among four MWCNT-APP-s, MWCNT-APP-Fe has the characteristics of moderate micropore/mesopore, significant hydrophobicity, redox property and functional groups. Interestingly, the redox reaction of Fe3+/Fe2+ and -C N-/-C N- transformation give MWCNT-APP-Fe an energy storage basis of pseudocapacitance, while MWCNTs and the micro/mesopore structure in MWCNT-APP-Fe provide a double-layer energy storage platform. As expected, on base of the dual energy storage mechanism, the symmetric supercapacitor assembled with MWCNT-APP-Fe has a higher specific capacity (Cs, 421 F g−1 at 1 mV s−1) as well as a long-lasting stability of 94.8% capacity retention with 99% Coulombic efficiency after 10,000 cycles at 20 mV s−1. More notably, the relevant aqueous Zn2+ hybrid supercapacitor provides a high capacity (Cm) of 191 mAh g−1 at 0.5 A g−1 and a long duration of over 2000 cycles at 50 A g−1, with a capacity retention of 92.4%. In summary, MWCNT-APP-Fe with a dual energy storage mechanism enables a potential application as an electrode material for high-performance supercapacitor. [ABSTRACT FROM AUTHOR]

This article explores the synthesis and coordination behavior of 9,10-Diarsatriptycene, a unique molecule with potential applications in various fields. The authors focus on the synthesis of heavy pnictogen-containing DHT analogues using nonvolatile arsenic precursors, which eliminates the need for dangerous reagents. The structures of the synthesized compounds were analyzed, revealing the effects of the bridgehead element. The compounds were found to have different stability and coordination abilities, and one compound formed a supramolecular polymer structure. Further research is being conducted to explore the potential applications of these compounds. [Extracted from the article]

In the realm of studying supramolecular polymers using computer simulations, the task of generating appropriate initial structures poses a significant challenge, primarily owing to the extensive range of potential configurations. In this study, we introduce StackGen, an open-source framework designed to efficiently create energy-optimized one-dimensional supramolecular polymer structures with minimal computational overhead. This tool utilizes the particle swarm optimization (PSO) algorithm in conjunction with a semiempirical quantum mechanical approach to identify low-energy supramolecular stack configurations from a diverse set of possibilities. These configurations result from the translational and rotational adjustments of adjacent molecules around monomers along various axes. The tool also considers various structural factors, including the presence of functional side groups and the extent of intermolecular π – π stacking interactions. Extensive testing across different molecules demonstrates StackGen's ability to produce low-energy structures with negligible computational costs. Additionally, the tool incorporates features for optimizing PSO hyperparameters in real-time, thus improving convergence. The tool provides a convenient means of generating structures suitable for both molecular simulations and quantum mechanical calculations. [ABSTRACT FROM AUTHOR]

Multi-component supramolecular polymerization, which requires control over hydrophobic effects, hydrogen bonding, coordination interactions, and π-π stacking of the monomers, enables the preparation of functional materials at the molecular level. Here, we report the synthesis of two monomers of biphenyl-3,3',5,5'-tetracarboxamide derivatives with tetraethylene glycol and tetraethylene glycol sulfate at the tails. By themselves, they are poor monomers for aqueous supramolecular homopolymerization, but the presence of tetrahydrofuran as cosolvent or sodium chloride as additive leads to the self-assembly of the monomers. In the copolymerization experiments, we show that the coexistence of these non-ionic and anionic biphenyl tetracarboxamide-based monomers leads to synergetic supramolecular copolymerization. [ABSTRACT FROM AUTHOR]

Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles (FNPs). However, such exploration focusing on organic FNPs has not been achieved to date. Herein, we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene‐based bis‐ureidopyrimidinone monomers (bis‐UPys) to relate the size to the fluorescence of organic nanoparticles. At an equal concentration of bis‐UPys, a logarithmic relationship between them is built with a correlation coefficient higher than 0.96. Theoretical calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the nanoparticles. This leads to different nonradiative decay rates of the embedded and exposed bis‐UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface areas. The established fluorescence intensity‐size correlation possesses fine universality and reliability, and it is successfully utilized to estimate the sizes of other nanoparticles, including those in highly diluted dispersions of FNPs. This work paves a new way for the simple and real‐time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect. [ABSTRACT FROM AUTHOR]

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Comprehensive Summary: Chiral supramolecular assembly of π‐conjugated luminophores provides a promising avenue for enhancing circularly polarized luminescence. In this study, we shed light on the impact of π‐conjugation length on circularly polarized luminescent performance of the resulting supramolecular assemblies, by designing a tetra‐cyanostilbene monomeric compound alongside two dicyanostilbene control compounds. These cyanostilbene‐based compounds possess the ability to form chiral supramolecular polymers in toluene, driven by a synergistic combination of intermolecular hydrogen bonding and π–π stacking interactions. The extended π‐aromatic skeleton brings bathochromic‐shifted fluorescence and enhanced intermolecular stacking capability for the tetra‐cyanostilbene compound. Consequently, chiral supramolecular assemblies formed by the tetra‐cyanostilbene compound demonstrate a remarkable two‐fold increase in glum values relative to the assemblies formed by the dicyanostilbene compounds. Overall, this study provides valuable insights into the relationship between π‐conjugation length and the circularly polarized luminescent performance of π‐conjugated supramolecular assemblies. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots (QDs) exhibit important photophysical properties, such as long‐range energy diffusion, miniband formation, and collective photoluminescence, when aggregated into well‐defined superstructures, such as three‐dimensional (3D) and two‐dimensional (2D) superlattices. However, the construction of one‐dimensional (1D) QD superstructures, which have a simpler arrangement, is challenging; therefore, the photophysical properties of 1D‐arranged QDs have not been studied previously. Herein, we report a versatile strategy to obtain 1D‐arranged QDs using a supramolecular polymer (SP) template. The SP is composed of self‐assembling cholesterol derivatives containing two amide groups for hydrogen bonding and a carboxyl group as an adhesion moiety on the QDs. Upon mixing the SP and dispersed QDs in low‐polarity solvents, the QDs self‐adhered to the SP and self‐arranged into 1D superstructures through van der Waals interactions between the surface organic ligands of the QDs, as confirmed by transmission electron microscopy. Furthermore, we revealed efficient photoinduced fluorescence resonance energy transfer between the 1D‐arranged QDs by an in‐depth analysis of the emission spectra and decay curves. [ABSTRACT FROM AUTHOR]

Diabetic wound healing poses a significant challenge, and there is a growing need to develop a comprehensive treatment approach in this field of research. Recently, natural lipoic acid has garnered considerable attention because it can polymerize through dynamic disulfide bonds. Here, we developed an α-lipoic acid (LA) supramolecular polymer-based hydrogel (BI-AuLA) with gold nanostars (AuNSs), in which the bovine insulin (BI) improved diabetic wound healing. The LA supramolecular polymer plays a crucial role in restoring the damaged redox microenvironment by effectively regulating the balance between reactive oxygen species and glutathione. Additionally, the photothermal properties of AuNSs enable BI-AuLA to exhibit outstanding antibacterial activity against a range of bacteria when subjected to near-infrared (NIR) irradiation. Furthermore, BI-AuLA facilitates the sustained release of BI, thereby regulating local high glucose levels in the wound. Significantly, in the diabetes mellitus skin defect model, BI-AuLA induces intensive blood vessel formation and promotes uniform collagen arrangement, thereby facilitating effective wound healing. This groundbreaking supramolecular polymer-based hydrogel represents a highly embodied and tremendously encouraging strategy for addressing the challenges posed by extensive tissue damage resulting from diabetes.

When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition.

Selective preparation of two-dimensional polymers (2DPs) and supramolecular polymers (2DSPs) with defined thickness is crucially important for controlling and maximizing their functions, yet it has remained as a synthetic challenge. In the past decade, several approaches have been developed to allow selective preparation of discrete monolayer 2DPs and 2DSPs. Recently, crystal exfoliation and self-assembly strategies have been employed to successfully prepare bilayer 2DP and 2DSP, which represent the first step towards the controlled "growth" of 2D polymers from the thinnest monolayers to thicker few-layers along the third dimension. This Concept review discusses the concept of accurate synthesis of 2D polymers with defined layers. Advances in this research area will pave the way to rational synthetic strategies for 2D polymers with controlled thickness.

We here present how rebalancing the interplay between H‐bonds and dispersive forces (Van der Waals/π–π stacking) may induce or not the generation of kinetic metastable states. In particular, we show that extending the aromatic content and favouring the interchain VdW interactions causes a delay into the cooperative supramolecular polymerization of a new family of toluene bis‐amide derivatives by trapping the metastable inactive state. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry enables the manipulation of functional components on a molecular scale, facilitating a "bottom-up" approach to govern the sizes and structures of supramolecular materials. Using dynamic non-covalent interactions, supramolecular polymers can create materials with reversible and degradable characteristics and the abilities to self-heal and respond to external stimuli. Pillar[n]arene represents a novel class of macrocyclic hosts, emerging after cyclodextrins, crown ethers, calixarenes, and cucurbiturils. Its significance lies in its distinctive structure, comparing an electron-rich cavity and two finely adjustable rims, which has sparked considerable interest. Furthermore, the straightforward synthesis, uncomplicated functionalization, and remarkable properties of pillar[n]arene based on supramolecular interactions make it an excellent candidate for material construction, particularly in generating interpenetrating supramolecular polymers. Polymers resulting from supramolecular interactions involving pillar[n]arene find potential in various applications, including fluorescence sensors, substance adsorption and separation, catalysis, light-harvesting systems, artificial nanochannels, and drug delivery. In this context, we provide an overview of these recent frontier research fields in the use of pillar[n]arene-based supramolecular polymers, which serves as a source of inspiration for the creation of innovative functional polymer materials derived from pillar[n]arene derivatives. [ABSTRACT FROM AUTHOR]

Although sulfur-containing polymers have been realized by various methods such as copolymerization and reverse vulcanization, there are few reports on the synthesis of supramolecular sulfur-containing polymers in which a supramolecular polymer is fused with a sulfur-containing polymer. Herein, we prepare a supramolecular sulfur-containig polymer by introducing a 2-ureido-4[1H]pyrimidinone (UPy) unit at both ends of linear sulfur and connecting between the UPys via hydrogen bonding. [ABSTRACT FROM AUTHOR]

A novel [c2] daisy chain was successfully constructed by the hermaphroditic monomer of dibenzo[24]-crown-8 (DB24C8) derivative bearing secondary ammonium salt (1) from the analysis of the solution-phase behavior of parent monomers and single-crystal X-ray analysis. 1H NMR spectroscopy was employed to show that the crown ether moiety and the secondary ammonium salt unit underwent acid–base and alkali metal cation dependent switches. The complexation behavior of this hermaphroditic monomer in the solution was further demonstrated to exhibit the controlled photophysical behavior as a reversible luminescent switch in the presence of acids or bases. Solid morphology was determined by SEM. [ABSTRACT FROM AUTHOR]

The generation of chirality in supramolecular structures from achiral building blocks has remained a challenge for a long time. In this study, we present a vortex-assisted chiral supramolecular polymerization from a series of achiral C3-symmetric monomers, where the mechanism of symmetry-breaking is systematically investigated. By increasing the supersaturation, at the early stage of nucleation and growth, highly ordered assemblies can be generated as the initial chiral nuclei. Meanwhile, chiral assemblies from high supersaturation are hard to interwind into clusters, where clusters as nuclei are not conducive to being fractured by sheer force of vortex fluid. Therefore, it is concluded that chiral assemblies in the nucleation stage possess low energy barrier, so that chiral nuclei could be fractured and replicated by the vortex. By enlarging the initial chiral bias, the major chiral nuclei can evolute into the final chiral polymers. [ABSTRACT FROM AUTHOR]

Insolubility of functional molecules caused by polymorphism sometimes poses limitations for their solution‐based processing. Such a situation can also occur in the preparation processes of supramolecular polymers formed in a solution. An effective strategy to address this issue is to prepare amorphous solid states by introducing a "coformer" molecule capable of inhibiting the formation of an insoluble polymorph through co‐aggregation. Herein, inspired by the coformer approach, we demonstrated a solubility enhancement of a barbiturate π‐conjugated compound that can supramolecularly polymerize through six‐membered hydrogen‐bonded rosettes. Our newly synthesized supramolecular coformer molecule features a sterically demanding methyl group in the π‐conjugated unit of the parent molecule. Although the parent molecule exhibits low solubility in nonpolar solvents due to the formation of a crystalline polymorph comprising a tape‐like hydrogen‐bonded array prior to the supramolecular polymerization, mixing with the coformer compound enhanced the solubility by inhibiting mesoscopic organization of the tapes. The two monomers were then co‐polymerized into desired helicoidal supramolecular polymers through the formation of heteromeric rosettes. [ABSTRACT FROM AUTHOR]

Nonionic hydrogels are of particular interest for long‐term therapeutic implantation due to their minimal immunogenicity relative to their charged counterparts. However, in situ formation of nonionic supramolecular hydrogels under physiological conditions has been a challenging task. In this context, we report on our discovery of salt‐triggered hydrogelation of nonionic supramolecular polymers (SPs) formed by self‐assembling prodrug hydrogelators (SAPHs) through the Hofmeister effect. The designed SAPHs consist of two SN‐38 units, which is an active metabolite of the anticancer drug irinotecan, and a short peptide grafted with two or four oligoethylene glycol (OEG) segments. Upon self‐assembly in water, the resultant nonionic SPs can be triggered to gel upon addition of phosphate salts. Our 1H NMR studies revealed that the added phosphates led to a change in the chemical shift of the methylene protons, suggestive of a disruption of the water‐ether hydrogen bonds and consequent reorganization of the hydration shell surrounding the SPs. This deshielding effect, commensurate with the amount of salt added, likely promoted associative interactions among the SAPH filaments to percolate into a 3D network. The formed hydrogels exhibited a sustained release profile of SN‐38 hydrogelator that acted potently against cancer cells. [ABSTRACT FROM AUTHOR]

Abstract Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles (FNPs). However, such exploration focusing on organic FNPs has not been achieved to date. Herein, we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene‐based bis‐ureidopyrimidinone monomers (bis‐UPys) to relate the size to the fluorescence of organic nanoparticles. At an equal concentration of bis‐UPys, a logarithmic relationship between them is built with a correlation coefficient higher than 0.96. Theoretical calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the nanoparticles. This leads to different nonradiative decay rates of the embedded and exposed bis‐UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface areas. The established fluorescence intensity‐size correlation possesses fine universality and reliability, and it is successfully utilized to estimate the sizes of other nanoparticles, including those in highly diluted dispersions of FNPs. This work paves a new way for the simple and real‐time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.

To develop a bulk supramolecular polymer based on 1,3,5‐benzenetricarboxamide (BTA) without crystallinity at room temperature, C3‐synmetrical BTA derivatives with two‐armed alkyl groups were synthesized and characterized. IR and XRD measurements of the BTA derivatives suggested that the higher‐order structure obtained using these materials was hexagonal columnar, owing to the characteristic three‐fold hydrogen bonding. In DSC measurements, BTA having 10‐nonadecyl groups (10NDBTA) showed only a single transition point at 233 °C and maintained its mesophase down to −50 °C, whereas the other BTA derivatives showed a transition peak in the range of 20 to 131 °C and another in the range of 204 to 239 °C, corresponding to alkyl melting and dissociation of the stacked BTA cores, respectively. 13C‐SSNMR measurement of 10NDBTA indicated that not only the 10‐nonadecyl groups of the side chains but also the BTA cores forming the main chain of the supramolecular polymer show a unique high mobility even at ambient temperature. [ABSTRACT FROM AUTHOR]

Controlling the nanoscale orientation of π‐conjugated systems remains challenging due to the complexity of multiple energy landscapes involved in the supramolecular assembly process. In this study, we have developed an effective strategy for programming the pathways of π‐conjugated supramolecular polymers, by incorporating both electron‐rich methoxy‐ or methanthiol‐benzene as donor unit and electron‐poor cyano‐vinylenes as acceptor units on the monomeric structure. It leads to the formation of parallel‐stacked supramolecular polymers as the metastable species through homomeric donor/acceptor packing, which convert to slip‐stacked supramolecular polymers as the thermodynamically stable species facilitated by heteromeric donor‐acceptor packing. By further investigating the external seed‐induced kinetic‐to‐thermodynamic transformation behaviors, our findings suggest that the donor‐acceptor functionality on the seed structure is crucial for accelerating pathway conversion. This is achieved by eliminating the initial lag phase in the supramolecular polymerization process. Overall, this study provides valuable insights into designing molecular structures that control aggregation pathways of π‐conjugated nanostructures. [ABSTRACT FROM AUTHOR]

Self-healing coatings mainly include externally assisted self-healing coatings based on the addition of repair agent and intrinsic selfhealing coatings based on reversible bond crosslinking polymers.The intrinsic self-healing coatings have attracted extensive attention due to their multiple repairable properties.In this paper，the self-healing technology based on crosslinking polymers containing reversible covalent bonds such as reversible imine bond，reversible disulfide bond，reversible Diels-Alder reaction and reversible urea bond，as well as the selfhealing mechanism，performance characteristics and difficulties of supramolecular crosslinked polymers based on reversible non-covalent bonds such as hydrogen bond，metal-ligand coordination bond and π - π stacking were discussed in detail.Besides，the application of self-healing technology based on reversible crosslinking polymers in coatings was also discussed.

Polymer networks containing transient physical and permanent chemical cross-links exhibit unique mechanical properties due to the intrinsic reassociating ability of supramolecular functional groups. Similar to supramolecular gels, these networks allow the controlled release of stored energy and can extend the life of polymer networks in practical applications. In this study, we investigated the rheology, dielectric spectroscopy, stress–strain behavior, and dynamic mechanical analysis of networks based on long polybutylene oxide (PBO) chains functionalized with randomly placed thymine (Thy) side groups. A transient network was formed by proportionally mixing this matrix with short non-entangled linear 1,3,5-diaminotriazine (DAT) head–tail modified PBO chains, exploiting the hetero-complementarity of the DAT–Thy triple hydrogen bond. This transient polymer network was further cross-linked to a dual network via a thiol-ene click reaction to form static covalent bonds. In PBO, the similar polarity of the PBO matrix and the DAT–Thy functional groups ensures that the molecular chain motion is not affected by segregation, resulting in a homogeneous polymer phase without microphase-separated functional group domains. Dielectric relaxation spectroscopy was combined with rheology to quantify the relaxation processes of the interconnected polymers and the strength of the DAT–Thy bonding interactions in the melt. The results showed two distinct plateaux in the relaxation modulus due to contributions from hydrogen and permanent bonds. In the case of the dual network, the lifetime of the hydrogen bond was prolonged and higher activation energy was observed due to the physical cross-link preventing the movement of the long chain.

Regioselective di‐functionalization of a cyclodextrin allows hydrophobic domains to be directed in a geometrically controlled manner. This controlled orientation ultimately gives access to an original hierarchical assembly in the solid state. This assembly spans over three levels of hierarchy which are governed by synergistic host‐guest inclusions, directed hydrophobic effect and hydrogen bonding. This combination of interactions precisely positioned in space through regioselective functionalization of a cyclodextrin creates a porous organic architecture. [ABSTRACT FROM AUTHOR]

The nucleation-elongation cooperative mechanism, as widely adopted by natural systems such as microtubules and actin filaments, exhibits superior properties for supramolecular systems in comparison to the isodesmic mechanism by avoiding the formation of short-ranged oligomers. In this study, a novel type of artificial supramolecular polymers with the nucleation-elongation mechanism have been constructed by incorporating hydrogen bonding recognition motifs adjacent to the cyanostilbene core. It facilitates the combination of hydrogen bonds and π-π stacking interactions between the neighboring monomers in a synergistic manner. The different hydrogen bonding units (urea versus amide) exert crucial impacts on the supramolecular polymerization behaviors, which can be qualified by the thermodynamic parameters of the self-assembly processes. Furthermore, supramolecular polymerization imparts confinement effect to the cyanostilbene unit, giving rise to the specific formation of [2+2] cycloaddition products under 430 nm photo-irradiation. It is in stark contrast to that in the monomeric state, which undergoes Z/E photoisomerization reactions under the same conditions. Overall, the current study provides new insights to modulate multi-path photochemical reactions in a precise manner. [ABSTRACT FROM AUTHOR]

Supramolecular polymer networks (SPNs) demonstrate great potential in the development of smart materials owing to their attractive dynamic properties. However, as they suffer from the inherent weak bonding of most noncovalent cross‐links, it remains a significant challenge to construct SPNs with outstanding mechanical performance. Herein, we exploit the cryptand/paraquat host‐guest recognition motifs as cross‐links to prepare a class of highly strong and tough SPNs. Unlike those supramolecular cross‐links with relatively weak binding abilities, the cryptand‐based host‐guest interactions have a high association constant and steady complexing structure, which effectively stabilizes the network and resists mechanical deformation under external force. Such favorable structural stability endows our SPNs with greatly enhanced mechanical performance, compared with the control‐1 cross‐linked by the weakly complexed crown ether/secondary ammonium salt motif (tensile strength: 21.1±0.5 vs 2.8±0.1 MPa; Young's modulus: 102.6±4.8 vs 2.1±0.3 MPa; toughness: 90.4±2.0 vs 10.8±0.6 MJ m−3). Moreover, our SPNs also retain abundant dynamic properties including good abilities in energy dissipation, reprocessability, and stimuli‐responsiveness. These findings provide novel insights into the preparation of SPNs with enhanced mechanical properties, and promote the development of high‐performance intelligent supramolecular materials. [ABSTRACT FROM AUTHOR]

A water-soluble metallo-supramolecular polymer MSP-f-6Np, which possesses a regular pore aperture of 1.4 nm, has been assembled from a structurally flexible naphthalene-appended [Ru(bipy)3]2+ complex and cucurbit[8]uril. As the first periodic metallo-supramolecular polymer formed by a flexible building block, MSP-f-6Np exhibits a hydrodynamic diameter of 122 and 164 nm at 0.1 and 2.0 mM of the monomer concentrations. Synchrotron small angle X-ray scattering experiments confirm that MSP-f-6Np possesses porosity periodicity in both the solution and solid states. Compared with a control, the new highly ordered porous system displays enhanced photocatalytic activity for the degradation of organic dyes.

Abstract Rational construction of flexible free-standing electrocatalysts featuring long-lasting durability, high efficiency, and wide temperature tolerance under harsh practical operations are fundamentally significant for commercial zinc–air batteries. Here, 3D flexible free-standing bifunctional membrane electrocatalysts composed of covalently cross-linked supramolecular polymer networks with nitrogen-deficient carbon nitride nanotubes are fabricated (referred to as PEMAC@NDCN) by a facile self-templated approach. PEMAC@NDCN demonstrates the lowest reversible oxygen bifunctional activity of 0.61 V with exceptional long-lasting durability, which outperforms those of commercial Pt/C and RuO2. Theoretical calculations and control experiments reveal the boosted electron transfer, electrolyte mass/ion transports, and abundant active surface site preferences. Moreover, the constructed alkaline Zn–air battery with PEMAC@NDCN air–cathode reveals superb power density, capacity, and discharge–charge cycling stability (over 2160 cycles) compared to the reference Pt/C + RuO2. Solid-state Zn–air batteries enable a high power density of 211 mW cm−2, energy density of 1056 Wh kg−1, stable charge–discharge cycling of 2580 cycles for 50 mA cm−2, and wide temperature tolerance from − 40 to 70 °C with retention of 86% capacity compared to room-temperature counterparts, illustrating prospects over harsh operations.

Herein, we present a mussel-inspired supramolecular polymer coating to improve the an-ti-corrosion and self-healing properties of an AZ31B magnesium alloy. A self-assembled coating of polyethyleneimine (PEI) and polyacrylic acid (PAA) is a supramolecular aggregate that takes advantage of the weak interaction of non-covalent bonds between molecules. The cerium-based conversion layers overcome the corrosion problem between the coating and the substrate. Catechol mimics mussel proteins to form adherent polymer coatings. Chains of PEI and PAA interact electrostatically at high density, forming a dynamic binding that causes strand entanglement, enabling the rapid self-healing properties of a supramolecular polymer. The addition of graphene oxide (GO) as an anti-corrosive filler gives the supramolecular polymer coating a superior barrier and impermeability properties. The results of EIS revealed that a direct coating of PEI and PAA accelerates the corrosion of magnesium alloys; the impedance modulus of a PEI and PAA coating is only 7.4 × 103 Ω·cm2, and the corrosion current of a 72 h immersion in a 3.5 wt% NaCl solution is 1.401 × 10−6 Ω·cm2. The impedance modulus of the addition of a catechol and graphene oxide supramolecular polymer coating is up to 3.4 × 104 Ω·cm2, outperforming the substrate by a factor of two. After soaking in a 3.5 wt% NaCl solution for 72 h, the corrosion current is 0.942 × 10−6 A/cm2, which is superior to other coatings in this work. Furthermore, it was found that 10-micron scratches were completely healed in all coatings within 20 min, in the presence of water. The supramolecular polymer offers a new technique for the prevention of metal corrosion. [ABSTRACT FROM AUTHOR]

Recent years have seen major advances in the additive manufacturing of stimuli‐responsive materials, also known as "4D printing," among which liquid crystal elastomers (LCEs) play an important role. However, during fabrication photo‐crosslinking of the LCEs is required, but this step is time‐consuming and efficient polymerization is challenging, especially in the case of light‐responsive materials. In this work, the first light‐fueled supramolecular LCEs suitable for the direct ink writing (DIW) of soft actuators are synthesized in which a photopolymerization step is not needed. With the responsive supramolecular material, 3D‐printed objects are fabricated by exploiting the thermoreversible interplay of the hydrogen‐bonding physical cross‐links. After printing, the supramolecular LCE shows reversible shape changes in response to light and is capable of bending and lifting a load. Through the combined photothermal and photochemical contributions of the incorporated azobenzene, the actuators can be triggered both in air and water. The freedom provided by DIW allows for the printing of complex responsive objects, as demonstrated by fabricating re‐entrant honeycomb and spiral director structures. This approach of printing light‐responsive supramolecular soft actuators opens avenues toward the application of "smart" and sustainable materials for additive manufacturing without the requirement of photo‐crosslinking. [ABSTRACT FROM AUTHOR]

Supramolecular polymers are materials that exhibit a range of functionalities and thus find wide applicability. In this study, two natural low‐molecular‐weight compounds, thioctic acid (TA) and phytic acid (PA), are used to fabricate polymeric supramolecular structures. The coexistence of dynamically covalently linked poly(TA) and hydrogen bond linked poly(PA) moieties result in copolymeric materials with different dynamic features. The obtained poly(TA‐PA)s show rapid and strong adhesion on a variety of natural and artificial surfaces, with high 180° peeling, lap‐shear, and pull‐off strengths over wide temperature (−18 °C to 60 °C) and humidity (20−99%) ranges. The poly(TA‐PA)s also display good stability and adhesion in the presence of water, even show stable and long‐lasting underwater adhesion. Hence, the synthesized poly(TA‐PA)s, which have high water resistance, are suitable for use as sealing materials in various applications, thus highlighting the applicability of supramolecular polymer materials in underwater surface coatings and adhesion. [ABSTRACT FROM AUTHOR]

Proper monomer design is the key to enhancing the strength of noncovalent interactions between the molecules toward the efficient formation of supramolecular polymers (SPs). We have designed and synthesized 1,n′‐disubstituted ferrocene‐azobenzene‐long alkyl chains, Fc(CONH‐Azo‐TDP)2, to afford SPs with a high probability. The design exploits the "molecular ball‐bearing" property of the ferrocene core, which allows two azobenzene arms to rotate in the planes of cyclopentadienyl rings, generating the most suitable molecular conformation required for SP formation. This ferrocene monomer formed a supergel consisting of SPs supported by strong intermolecular (H‐bonding and π‐π stacking) interactions and higher enthalpy gain than the reference molecules, where the central ferrocene core was replaced by flexible aliphatic as well as rigid benzene linkers. The molecular conformation involved in SPs, the strength of noncovalent interactions, and the process of supramolecular polymerization were investigated through NMR, UV‐Vis, XRD and TEM studies. The results demonstrate that ferrocene may act as a good modulator for constructing efficient SPs. [ABSTRACT FROM AUTHOR]

A series of poly(lactide) (PLA)‐based supramolecular polymers based on linear PLLA‐b‐PCL‐b‐PLLA triblock copolymers (PLLA, poly(l‐lactide); PCL, poly(ε‐caprolactone)) or/and three‐arm star (PCL‐b‐PDLA)3 block copolymers (PDLA, poly(d‐lactide)) were synthesized. The effects of the structure and composition on crystal structure, crystallization behavior, spherulite morphology and mechanical properties of the synthesized supramolecular polymers were investigated. The results of DSC and polarized optical microscopy indicated that the supramolecular polymer exhibited poor crystallization ability with respect to PCL/PLA block copolymer, and the crystallinity of the supramolecular polymer with alternating PCL/PLA multiblock structure was stronger than that with similar crosslinked network structure. The presence of molten PCL blocks disturbed the orientation of lamellae, forming spherulites with feather‐like dendrites, and ring‐banded spherulites were observed as the molecular weight of the PLA blocks increased. The results of tensile tests demonstrated that supramolecular polymers with larger molecular weight of PLA blocks showed the pronounced ductile fracture. On this basis, stereocomplexed supramolecular polymers were also synthesized, and it was found that the stereocomplex crystals had a significant impact on the crystallization and mechanical properties of the supramolecular polymers. Therefore, in this work a novel technique for manufacturing toughened PLA‐based material and tuning its performances is proposed, which may promote the application of PLA‐based materials in more fields. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry enables the manipulation of functional components on a molecular scale, facilitating a “bottom-up” approach to govern the sizes and structures of supramolecular materials. Using dynamic non-covalent interactions, supramolecular polymers can create materials with reversible and degradable characteristics and the abilities to self-heal and respond to external stimuli. Pillar[n]arene represents a novel class of macrocyclic hosts, emerging after cyclodextrins, crown ethers, calixarenes, and cucurbiturils. Its significance lies in its distinctive structure, comparing an electron-rich cavity and two finely adjustable rims, which has sparked considerable interest. Furthermore, the straightforward synthesis, uncomplicated functionalization, and remarkable properties of pillar[n]arene based on supramolecular interactions make it an excellent candidate for material construction, particularly in generating interpenetrating supramolecular polymers. Polymers resulting from supramolecular interactions involving pillar[n]arene find potential in various applications, including fluorescence sensors, substance adsorption and separation, catalysis, light-harvesting systems, artificial nanochannels, and drug delivery. In this context, we provide an overview of these recent frontier research fields in the use of pillar[n]arene-based supramolecular polymers, which serves as a source of inspiration for the creation of innovative functional polymer materials derived from pillar[n]arene derivatives.

Supramolecular polymers self-assemble into nanofibers, micelles, and other nanostructures through weak noncovalent interactions between subunits. Such systems possess attractive properties for use in a variety of practical settings such as energy, sustainability, and healthcare. In regenerative medicine, a common approach involves implanting a supramolecular material containing cell and growth factor binding motifs directly into a diseased or traumatized tissue defect, whereupon it interacts with and/or recruits components of the biological system to induce tissue healing. Here we introduce a supramolecular therapeutic in which tissue regeneration is orchestrated by a supramolecular polymer prodrug implanted subcutaneously in a remote tissue. Our approach exploits a hydrophobic small-molecule inhibitor of prolyl hydroxylase enzyme as both a regeneration-inducing therapeutic and a structure-directing agent in a supramolecular polymer that forms shear-thinning nanofiber hydrogels. Subcutaneous injection of the supramolecular hydrogel in the back of mice wounded with a critical-sized defect in the ear led to transient upregulation of hypoxia inducible factor-1α and regeneration of ear tissue in a manner reminiscent of epimorphic regeneration. This drug-induced regeneration strategy utilizes a simple and translatable supramolecular design, eliminates the need for delivery of biologics ( e. g., growth factors, cells), and avoids implantation of a foreign material directly in a tissue defect.

The topology of polymers plays an essential role in their chemical, physical and biological properties. However, their effects on chirality-related functions remain unclear. Here, we reported the topology-controlled chirality expression in the chiral supramolecular system for the first time. Two topological supramolecular polymers, hyperbranched (HP) and linear (LP) supramolecular polymers produced by the host–guest interactions of branched and linear monomers, respectively, exhibited completely different chirality expressions despite the same molecular chirality of their monomers. Significantly, due to the branch points and strong steric hindrance existing in HP, cis-HP showed an enhanced and sign-inverted Cotton effect in the n–π* bands compared with cis-LP, as a result that the distinctive chirality induction and transfer were controlled by the topological skeletons. This topology-controlled chirality induction and transfer in the photoswitchable supramolecular polymers not only enables us to elucidate the in-depth effects of topology on the chiral expression in biopolymers but also inspires the design of chiroptical and bioinspired materials.

Abstract Supramolecular polymers are materials that exhibit a range of functionalities and thus find wide applicability. In this study, two natural low‐molecular‐weight compounds, thioctic acid (TA) and phytic acid (PA), are used to fabricate polymeric supramolecular structures. The coexistence of dynamically covalently linked poly(TA) and hydrogen bond linked poly(PA) moieties result in copolymeric materials with different dynamic features. The obtained poly(TA‐PA)s show rapid and strong adhesion on a variety of natural and artificial surfaces, with high 180° peeling, lap‐shear, and pull‐off strengths over wide temperature (−18 °C to 60 °C) and humidity (20−99%) ranges. The poly(TA‐PA)s also display good stability and adhesion in the presence of water, even show stable and long‐lasting underwater adhesion. Hence, the synthesized poly(TA‐PA)s, which have high water resistance, are suitable for use as sealing materials in various applications, thus highlighting the applicability of supramolecular polymer materials in underwater surface coatings and adhesion.