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Ionic conductors, such as hydrogels, ionogels, and eutectogels, have attained considerable research interest in various advanced application scenarios. However, such ionic conductors still suffer from the restriction of inherent liquid compositions, which may leak or evaporate. Herein, inspired by the control strategy of desertification caused by soil erosion, a novel internal‐external dual enhancement design strategy, i.e., increasing the interaction between the filler itself and its matrix, is proposed to firmly embed the deep eutectic solvent (DES) into polyurethane (PU) to prevent liquid leakage, such that the prepared ionic conductive elastomers (PU‐DESs) are quasi‐solid. The PU‐DESs exhibit marvelous versatility including high stretchability, tensile strength, toughness, self‐healing efficiency, antibacterial ability, ionic conductivity, and excellent freezing tolerance. More intriguingly, benefiting from their quasi‐solid feature, PU‐DESs are endowed with long‐term environmental stability. Thanks to these superb versatile features, PU‐DESs are further successfully applied in the wearable sensor and triboelectric nanogenerator (TENG) for monitoring human motions and converting mechanical energy into electrical energy, breaking away from the limitations of previous most soft iontronics such as liquid leakage or evaporation and weak mechanical strength. Hence, this study establishes an effective material design strategy for various soft iontronics demanding environmental stability and durability. [ABSTRACT FROM AUTHOR]

Polymer micelles have attracted much attention in the field of controlled drug release because of their excellent hydrophobic drug solubility and fewer drug side effects. However, insufficient sensitivity, insufficient dilution resistance, and ordinary therapeutic effect severely restrict the further development of current drug‐loaded polymer micelles. Here, the ditelluride group was introduced for the first time into fluorinated Gemini amphiphilic polymer (FnH12DiTeFnH12) to fabricate polymeric micelles used for controlled release. Camptothecin (CPT) loaded in the FnH12DiTeFnH12 micelles can be rapidly released in a controlled manner through the cleavage of ditelluride bonds by mild H2O2 and glutathione. Meanwhile, the synergism effect of the superhydrophobicity of the fluorocarbon chain and the special Gemini structure endows the drug‐loaded polymer micelles with excellent stability and drug‐loading content. Moreover, the in vitro studies revealed that the CPT@FnH12DiTeFnH12 micelles exhibited efficient uptake in Hela cells. Notably, about five times lower dosage of loaded CPT had a higher tumor cells growth inhibition than the free CPT, and cell membrane permeability became better with the increase of the fluorocarbon chain length. The CPT@FnH12DiTeFnH12 micelles exhibit excellent physical and chemical properties and good therapeutic effects, indicating their excellent potential for drug delivery and providing a novel avenue for chemotherapy. [ABSTRACT FROM AUTHOR]

A series of novel nonionic hydrocarbon/fluorocarbon hybrid surfactants (Hm-Fn, where m = 10, 12, 14, 16 and n = 4, 6, respectively) were successfully synthesized using polyethylene glycol, isophorone diisocyanate (IPDI), short chain fluoroalkyl alcohol and alkyl alcohol as starting materials. The preparation process involves the coupling reaction of isocyanate and hydroxyl groups. The surface activity and aggregation behavior of Hm-Fn in aqueous solution were studied by surface tension, steady-state fluorescence and dynamic light scattering (DLS) and transmission electron microscopy (TEM). The influence of the hydrophobic (hydrocarbon or fluorocarbon) chain length on surface activity of such hydrocarbon/fluorocarbon hybrid surfactants was systematically investigated. Micromorphology analysis revealed the presence of different sizes vesicles in H16-F6 and H16-F4 aqueous solution. In addition, the hydrophobic dye solubilization experiments exhibited that H16-F6 with a relatively longer fluorocarbon chain and hydrocarbon chain possessed more outstanding solubilization of model dye (Sudan I) compared with other Hm-Fn and conventional hydrocarbon surfactants. The molar solubilization power of H16-F6 could reach 0.0537. The above results demonstrated that these nonionic hydrocarbon/fluorocarbon hybrid surfactants might possess potential application prospects for hydrophobic dyes solubilization. [ABSTRACT FROM AUTHOR]

In this work, we first synthesized modified cellulose nanocrystals (MCNC) with 2,4‐toluene diisocyanate and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide via a two‐step in‐situ polymerization method, and then incorporated it with shape memory polyurethane (SMPU) to fabricate composite. It was found that the urethane chains and phosphorus‐containing flame retardant were covalently grafted onto the cellulose nanocrystals surface, and the MCNC exhibited good dispersion level in the SMPU matrix. Due to the crystallization‐induced and flame retardant effects of the prepared MCNC, it could be acted as a multifunctional reinforcer in SMPU composites. Noticeably, the most balanced improvements in crystallization, shape memory, mechanical, thermal stability, and flame retardancy properties of composites were observed with the incorporation of 3 wt% MCNC. Shape memory experiment demonstrated that the SMPU‐MCNC3 composite exhibited admirable thermal induced shape memory behavior, and its shape fixity and shape recovery ratios were maintained above 90% after five cycles. More importantly, the SMPU‐MCNC3 composite showed well balanced mechanical (σb = 13.1 MPa, εb = 189.3%), limiting oxygen index (23.8%), and UL‐94 rating (V‐2) among the prepared polyurethane films. In addition, the representative SMPU‐MCNC3 showed obviously reductions in heat and smoke production during combustion as compared to the neat SMPU. The present work offers a promising route to fabricate shape memory polyurethane composites with versatile functions. [ABSTRACT FROM AUTHOR]

Bionic ionic skin, having the ionic transduction and chromotropic traits of chameleons, along with multiple sensing, antibacterial, self-healing, and anti-freezing functions, is of great importance in a wide range of applications, such as flexible iontronics, health monitoring systems, and smart wearable devices. Although such advanced intelligence universally exists in natural organisms, these characteristics are rarely achieved in artificial materials simultaneously. By mimicking biological skin, here, a novel electromechanical and mechanochromic dual-sensing ionic skin (DSI-skin) with these superior functions is presented for visually monitoring human motions and expiration. The DSI-skin is mainly generated by the introduction of highly-substituted hydroxypropyl cellulose (H-HPC) forming liquid-crystal structures into a multifunctional ionic hydrogel (MFIH) containing Al3+ ions with ionic conduction. The resulting DSI-skin is the first to realize simultaneously sensitive dual-mode sensing of strain (gauge factor: 4.90; response time: 363 ms; mechanochromic sensitivity: 2.14 nm per %), pressure (sensitivity: 3.14 kPa−1; response time: 631 ms; mechanochromic sensitivity: 8.02 nm kPa−1), and humidity (fast response: 0.5 s; wide range: 30–90% RH) via the change of structure color and resistance. More importantly, owing to the highly synergistic effect of Al3+ ions and H-HPC, the DSI-skin is simultaneously integrated with handy color tuning (426–641 nm), outstanding antibacterial (log reduction > 3.43), excellent self-healing (85.0% efficiency), and anti-freezing (−15 °C) functions for the first time. These utility functions prolong the service life of the materials and expand their applications in many fields. Interestingly, the DSI-skin is also created with Zn2+ ions. Thus, this investigation provides insights into the design and fabrication of high-performance biomimetic materials. [ABSTRACT FROM AUTHOR]

Herein, a novel type of visible-light-induced dynamic covalent bond was developed based on aromatic Schiff base (ASB) bonds, and the prepared waterborne polyurethanes containing dynamic ASB bonds (ASB-WPU) exhibited a desirable self-healability (healing efficiency of 83.8%) after healing under a commercial LED table lamp for 24 hours (temperature of ∼25 °C). Meanwhile, high mechanical properties (tensile stress of 14.32 MPa and toughness of 64.80 MJ m−3) could also be obtained, demonstrating a good balance of room-temperature self-healability and high mechanical properties in our polymers. The imine metathesis of ASB bonds and the H-bonded interactions between urethane groups could afford the ultimate healing result simultaneously, in which the imine metathesis of ASB bonds triggered by visible light is the main factor. Furthermore, these ASB-WPU polymers could also be reprocessed under visible light with well recovered mechanical properties. We envision that this elaborate design philosophy, based on the readily available, clean, safe and easily manipulable visible light, could provide inspiration for preparing room-temperature self-healable and reprocessable polymers with high mechanical properties, which are urgently needed for next-generation smart materials. [ABSTRACT FROM AUTHOR]

The eradication of recalcitrant bacterial biofilm infections necessitates the development of speedy diagnostics and prompt therapeutics. However, constructing a portable versatile platform that enables in situ monitoring of biofilm infections accompanied by potent antibiofilm activity remains challenging. To address this conundrum, a microneedle theranostic patch (Mn: C/G@MN) is devised by incorporating an innovative biophotonic probe (manganese‐doped carbon dots, Mn: CDs) into methacrylated gelatin for visual monitoring of biofilm infection and on‐demand photo‐therapy. The Mn: C/G@MN patch penetrates the physical barrier of biofilms to track their acidic microenvironment, exhibiting a visualized fluorescence color change (from yellow to turquoise) to enable naked‐eye monitoring of biofilm infection. Furthermore, the Mn: C/G@MN patch can drastically eradicate biofilm on‐demand through the synergy of local hyperthermia and hydroxyl radical (•OH) storm under 808 nm near‐infrared light illumination, enabling the damaging of extracellular polymeric substances (EPS) matrix to disperse biofilms and subsequently kill detached bacteria. Both in vitro and in vivo findings authenticate that biofilm infection monitoring‐and‐treating can be achieved. Moreover, the versatile Mn: C/G@MN patch is conducive to suppressing inflammatory responses, expediting collagen deposition, stimulating angiogenesis, and accelerating biofilm‐infected wound healing. As envisaged, this work highlights the potential of such a versatile platform for application in integrated theranostics for biofilm infection. [ABSTRACT FROM AUTHOR]

To endow thermoset shape memory polymers with self-healing and recyclable functionalities is highly desirable. In this study, we fabricated Diels-Alder crosslinked polyurethane/functionalized reduced graphene oxide composites (DAPU-FRGOs) through in situ polymerization. The incorporated FRGO with urethane chains could achieve good compatibility with the DAPU matrix, forming physical and chemical crosslinking structures in the composite. And the most effective improvements of mechanical, thermal stability, crystallization-triggered, and photothermal effect were achieved for the DAPU/FRGO2 composite with 2 wt% FRGO. Owing to the outstanding crystallization-induced and photo-thermal effects of FRGO and the thermal reversible behavior of Diels-Alder bonds, the DAPU-FRGO2 composite showed rapid shape memory (<10 s, shape-fixity and recovery ratios were 92.3% and 94.1%, respectively) and self-healing (<120 s, healing efficiencies for tensile strength and elongation at break were 89.3% and 90.4%, respectively) under near-infrared light. Meanwhile, the DAPU-FRGO2 composite exhibited good repeatability of self-healing and shape-memory functionalities, and its shape memory parameters and healing efficiencies were maintained above 92% and 85% after three-cycles, respectively. Further recycling test demonstrated that the mechanical properties of the recycled DAPU-FRGO2 composite could be recovered to more than 82% of the original sample. This work provides a heuristic perspective for designing durable light-responsive thermoset shape memory composite materials. Image 1 • Dual-crosslinked DAPU-FRGOs composites were fabricated via in situ polymerization. • FRGO with urethane chains exhibited significantly enhanced compatibility with DAPU matrix. • Properties of composite were significantly enhanced with the introduction of 2 wt% of FRGO. • DAPU-FRGO2 composite showed excellent shape memory and self-healing under NIR light. • DAPU-FRGO2 composite exhibited good recyclability by NIR light and solution casting. [ABSTRACT FROM AUTHOR]

The aim of the present work is to provide a new retanning system for aldehyde-tanned leather, which can improve the physical-mechanical property of resultant leather and reduce the formaldehyde content in the resultant leather. This new retanning system consists of polyacrylic acid and gemini polyurethane surfactant, which are not harmful to human. The physical-mechanical property of leathers treated with different retanning system was analyzed, and the fiber structure of leather treated with the new complex retanning system was observed; the effects of some factors on the physical-mechanical property and formaldehyde content of leathers were studied, which were the hydrophobic chain length of gemini polyurethane surfactant, the offer percentage of retanning agent and the pH condition of retanning process. The results showed that the complex retanning system had better retanning effect, and the physical-mechanical property and formaldehyde content of leathers would be affected by above factors. When the hydrophobic chain length was eight and the offer percentage was 6%, the retanning effect was the best, and the thickening rate was 8.5%, the elongation and tear strength increased by 14.5% and 18.4%, respectively. At the same time, the reduction rate of formaldehyde content was 30.0%. Notably, when the value of pH decreased to 2.7 in the retanning stage, the reduction rate of formaldehyde content could increase to 39.3%. This retanning system had better retanning effect, which indicated that it would be helpful to the clean production of leather and the development of environmental protection. In addition, the work provided a good alternative to solve the other formaldehyde problems in our life. [ABSTRACT FROM AUTHOR]

Waterborne polyurethanes with higher mechanical properties, excellent self-healing efficiency under moderately controlled conditions and multiple functions are a sort of interesting and useful finishing materials for a wide range of applications. Herein, we prepared a multifunctional waterborne polyurethane (DTe-WPU) with ambient temperature self-healing, recyclable and antibacterial functions by introducing dynamic ditelluride bonds in the main chain. The film of synthesized waterborne polyurethane exhibits strong tensile strength (~17.5 MPa), satisfactory elongation (~860 %), and rapid self-healing (healing efficiency 85.4 % of stress, 91.99 % of stain, at ambient temperature visible light irradiation for 30 min). The film of DTe-WPU-2 can be recycled under pressure and visible light irradiation benefiting from the material's favorable self-healing properties, and the tensile stress of recycled material can be restored to >80 % of its original performance even after three recycle tests. Importantly, the introduction of ditelluride bonds can endow the finishing materials with good antibacterial properties (the antibacterial performance against Escherichia coli and Staphylococcus aureus showed 90.2 % and 92.5 %, respectively). Moreover, the leather coating finished with DTe-WPU-2 showed favorable self-healing properties. The present work will be hopefully developed as a facile designing method to fabricate environmentally friendly water dispersion polymers with fast ambient temperature self-repairing performance, recyclable and antimicrobial functions. [Display omitted] • A simple design method to fabricate environmentally friendly water-dispersible polymers with ditelluride bonds • With this method, rapid self-healing and recyclable under visible light ambient temperature was achieved. • Antibacterial properties of waterborne polyurethane films containing ditelluride bonds were first reported. • Leather coating can repair with mild healing conditions and simple operation. [ABSTRACT FROM AUTHOR]

It is still a great challenge to synthesize waterborne polyurethane (WPU) with excellent mechanical performance and fast room-temperature self-healing ability because of the mutually exclusive nature of these properties. Herein, a room-temperature self-healing waterborne polyurethane based on Zn2+-carboxyl coordination bond and hydrogen bond was prepared by adding zinc ion buffer solution to WPU emulsion. Due to the synergistic effect of dynamic coordination bonds and hydrogen bonds, the optimized sample (WPU-Zn-3) exhibited excellent mechanical properties (a tensile strength of 7.26 MPa, a elongation at break of 855 % and an exceptional toughness of 26.76 MJ/m3) and fast room-temperature self-healing capacity under ethanol induction (a high healing efficiency of 88 % within 4 h), showing a good balance between fast room temperature healing ability and excellent mechanical properties. Interestingly, this method also works for nickel ions but not for iron and aluminum ions. Furthermore, compared with zinc chloride and zinc nitrate, the waterborne polyurethane containing zinc acetate showed the best comprehensive performance. Due to the presence of zinc ions, the sterilization rates of WPU-Zn-3 film samples against Escherichia coli and Staphylococcus were 97.1 % and 97.8 %, respectively. Specially, we introduced graphene quantum dots into the waterborne polyurethanes to construct photoluminescence films and demonstrated their potential applications prospect in the fields of information encryption and anti-counterfeiting. This work broadens the avenue for fabricating room-temperature self-healing and multifunctional waterborne polyurethanes. [Display omitted] • A facile strategy to fabricate room-temperature healing WPU with coordination bond. • With this strategy, fast healing and robust mechanical properties are achieved simultaneously. • This strategy does not work for iron and aluminum ions, but for nickel and zinc ions. • The as-prepared WPU film exhibits excellent antibacterial properties. • WPU-Zn/GQDs composite film displays photoluminescence, information encryption and anti-counterfeiting. [ABSTRACT FROM AUTHOR]