is greatly decreased or even eliminated. For instance, the widely used cyanoacrylate adhesives exhibit strong adhesion in air, but when applied in water environment, they are hardened quickly to form a layer of stiff plastics, eventually resulting in the loss of adhesion. [9] The commercially available epoxy resins [10] and polyurethanes [11] are reported to demonstrate strong underwater adhesion, but long time of curing is usually required. Recently, host-guest chemistry strategy was reportedly employed to prepare underwater adhesives; however, the substrate surface needs to be modified in advance. [5,12] In addition, electrostatic and hydrophobic interactions were also proved to contribute to enhanced underwater adhesion, but the adhesion strength was relatively poor. [13,14] In nature, many organisms, such as mussels, barnacles, and castle worms, have evolved an unparalleled mechanism to perfectly tackle the underwater adhesion problem. [15][16][17] The finding of universality of catechol chemistry for wet adhesion has provided a valuable biomimetic source to develop diverse adhesives for use in aqueous environments. However, several problems, such as the complexity of administration, release of harmful organic solvents, [18,19] long-term curing, [2] need for oxidant addition, [20,21] and low adhesion strength, [18,22] may hamper the actual applications of these bioinspired adhesives. Although numerous dopamine-based adhesives have been reported and shown to bond various material surfaces, strong adhesion in water and particularly blood environment, remains nonexistent so far.Increasing studies on bioadhesives secreted by molluscs and insects have suggested that liquid coacervation plays a critical role in achieving underwater adhesion. [13] In this process, phase separation and concurrently increased hydrophobicity induced by coacervation can dispel the hydrated water on the interface, leading to much enhanced interaction of adhesive groups with the adherent and thus stable underwater adhesion. Up to date, several complex coacervate adhesives with linear structure have been reported, but the occurrence of those coacervations in water needs external triggers, such as temperature, [13] pH, [20,23] and iron strength. [24] Compared to linear counterparts, hyperbranched polymer (HBP) has a unique highly branched Despite recent advance in bioinspired adhesives, achieving strong adhesion and sealing hemostasis in aqueous and blood environments is challenging. A hyperbranched polymer (HBP) with a hydrophobic backbone and hydrophilic adhesive catechol side branches is designed and synthesized based on Michael addition reaction of multi-vinyl monomers with dopamine.It is demonstrated that upon contacting water, the hydrophobic chains selfaggregate to form coacervates quickly, displacing water molecules on the adherent surface to trigger increased exposure of catechol groups and thus rapidly strong adhesion to diverse materials from low surface energy to high energy in various environments, such as deionized water, sea ...

Developing an autonomous room temperature self‐healing supramolecular polyurethane (PU) with toughness and stiffness remains a great challenge. Herein, a novel concept that utilizes a T‐shaped chain extender with double amide hydrogen bonds in a side chain to extend PU prepolymers to construct highly stiff and tough supramolecular PU with integrated functions is reported. Mobile side‐chain H‐bonds afford a large flexibility to modulate the stiffness of the PUs ranging from highly stiff and tough elastomer (105.87 MPa Young's modulus, 27 kJ m−2 tearing energy), to solvent‐free hot‐melt adhesive, and coating. The dynamic side‐chain multiple H‐bonds afford an autonomous self‐healability at room temperature (25 °C). Due to the rapid reconstruction of hydrogen bonds, this PU adhesive demonstrates a high adhesion strength, fast curing, reusability, long‐term adhesion, and excellent low‐temperature resistance. Intriguingly, the PU emits intrinsic blue fluorescence presumably owing to the aggregation‐induced emission of tertiary amine domains induced by side‐chain H‐bonds. The PU is explored as a counterfeit ink coated on the predesigned pattern, which is visible‐light invisible and UV‐light visible. This work represents a universal and facile approach to fabricate supertough supramolecular PU with tailorable functions by chain extension of PU prepolymers with multiple H‐bonding chain extenders.

The single crystal of M-4-B was obtained by attaching the boron of BH3 to the amine linker between a tetraphenylethylene (TPE) unit and rhodamine B. M-4-B showed a novel sequential tricolor switching from dark blue to bluish-green and to a reddish color upon grinding. The boron atom played a key role in developing the single crystal.

Traditional insulation material is thermally insulating and has a low thermal conductivity. The miniaturisation and higher power of electrical devices would generate lots of heat, which have created new challenges to safe and stable operation of the grid. The development of insulating materials with high thermal conductivity provides a new method to solve these problems. The improvement of thermal conductivity would increase the ability to conduct heat and greatly reduce the operating temperature of the electrical equipment, which could reduce the equipment size and extend service life. On the other hand, inorganic thermally conductive particles and the improved thermal conductivity may have great effect on thermal breakdown. In this study, the factors affecting the thermal conductivity of dielectric polymer composites were explored. Intrinsic thermal conductive polymer and particle-filled thermal conductive composites were discussed. Effect of thermal conductivity, shape, size, surface treatment of the particle and prepare process on thermal properties of the composites were illustrated. This study focused on the electrical and thermal properties of thermally conductive epoxy, polyimide and polyethylene composites. Tracking failure caused by thermal accumulation is a typical thermal breakdown phenomenon. The performance of the resistance to tracking failure was studied for these composites. The results showed that thermal conductive particles improved the resistance to tracking failure. Finally, application of thermally conductive epoxy in electrical equipment was discussed. High Voltage

A mechanical-enhancer-monomer, N-acryloylsemicarbazide, is polymerized to make an ultra-stiff supramolecular polymer hydrogel that is exploited as a temporary vascular prosthesis.

Objective-To explore a direct and causal relationship between vascular hepcidin and atherosclerotic plaque stability. Methods and Results-Accelerated atherosclerotic lesions were established by perivascular collar placement in apolipoprotein E-deficient (ApoE -/-) mice. Adenoviral overexpression of hepcidin in the carotid artery during plaque formation enhanced intraplaque macrophage infiltration and suppressed the contents of collagen and vascular smooth muscle cells, whereas hepcidin shRNA treatment exerts opposite effects. The overexpression or knockdown of hepcidin did not affect plaque lipid deposition but increased or decreased oxidized low-density lipoprotein (ox-LDL) levels within intraplaque macrophages. In cultured macrophages, ox-LDL not only increased reactive oxygen species formation, inflammatory cytokine production, and apoptosis but also upregulated hepcidin expression. However, hepcidin did not exaggerate the ox-LDL-induced activation of macrophages until an onset of erythrophagocytosis. Whereas hepcidin was critical for the upregulation of L-ferritin and H-ferritin in both ox-LDLtreated erythrophagocytosed macrophages and atherosclerotic plaques, the adding of iron chelators suppressed the intracellular lipid accumulation, reactive oxygen species formation, inflammatory cytokine expression, and apoptosis in erythrophagocytosed macrophages. Conclusion-Hepcidin

Injectable hydrogels with the capability to cast a hypoxic microenvironment is of great potentialities to develop novel therapies for tissue regeneration. However, the relative research still remains at the conceptual phase. Herein, we chose diabetic wound as a representative injury model to explore the actual therapeutic results of tissue injury by injectable hypoxiainduced hydrogels. To enhance recovery and widen applicability, the hypoxia-induced system was incorporated with a conductive network by an original sequentially interpenetrating technique based on the combination of a fast "click chemistry" and a slow enzymatic mediated cross-linking. Hyperbranched poly(β-amino ester)-tetraaniline (PBAE-TA) was cross-linked with thiolated hyaluronic acid (HA-SH) via a thiol−ene click reaction, contributing to the rapid formation of the first conductive network, where vanillin-grafted gelatin (Geln-Van) and laccase (Lac) with a slow cross-linking rate were employed in casting a hypoxic microenvironment. The as-prepared injectable hydrogels possessed both suitable conductivity and sustainable hypoxia-inducing capability to upregulate the hypoxia-inducible factor-1α and connexin 43 expressions of the encapsulated adipose-derived stem cells, which enhanced vascular regeneration and immunoregulation and further promoted the reconstruction of blood vessels, hair follicles, and dermal collagen matrix, eventually leading to the recovery of diabetic rat skin wounds and restoration of skin functions. This work provides a promising strategy to broaden the applicability of diverse hydrogels with a long time-consuming gelation process and to integrate different networks with various biological functions for the therapies of diabetic wounds and other complex clinical symptoms.

A tunicate-inspired gelatin-based hydrogel prepared by a simple mixing method, exhibits strong adhesion and antibacterial capacity, and facilitates wound healing.