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Crown ethers demonstrate significant conformational flexibility and rotational symmetry, rendering them invaluable in the realms of supramolecular chemistry and crystal engineering. These unique natures facilitate the construction of supramolecular crystals of crown ethers, characterized by disorder‐order phase transitions, imparts unique properties that hold promise for diverse applications across multiple fields. In this study, four supramolecular compounds, namely [Na(15‐crown‐5)]BF4 (1), [Na(18‐crown‐6)]BF4⋅H2O (2), [K(15‐crown‐5)]BF4 (3) and [K(18‐crown‐6)]BF4⋅H2O (4) were synthesized and characterized by microanalysis, thermogravimetric analysis, differential scanning calorimetry and powder X‐ray diffraction techniques. Herein, 15‐crown‐5 and 18‐crown‐6 correspond to 1,4,7,10,13‐pentaoxacyclopentadecane and 1,4,7,10,13,16‐hexaoxacyclooctadecane, respectively. It was observed that the crystal structure, phase transition, and dielectric properties of these supramolecular compounds are significantly influenced by the size of the crown‐ether rings. The research extensively discussed the correlation between the coordination mode of metal ions of K+ or Na+ with crown ethers, the compatibility between metal ions and crown‐ether rings in terms of size, and the effects of crown‐ether disorder on dielectric permittivity during phase transitions. Our discoveries hold significant implications for the design and development of crown‐ether supramolecular functional materials. [ABSTRACT FROM AUTHOR]

Hydrogels have been attracting much attention as smart soft materials. The exploration of methods allowing hydrogels to have anisotropic composition, structure, and properties would benefit the fabrication of smart materials with versatile multi‐functions. Here we report the rapid frontal polymerization (FP) of bilayer hydrogels possessing good water swelling, mechanical strength, self‐healing, biocompatibility, and antibacterial capabilities. The bilayer hydrogels, consisting of poly(AM‐co‐AMPS) (G‐1) and poly(AM‐co‐HPA) (G‐2) (AM, acrylamide; AMPS, 2‐acrylamide‐2‐methylpropanesulfonic acid; HPA, hydroxypropyl acrylate), are synthesized in one step within 6 minutes (min) by horizontal FP. These polymer hydrogels have hierarchical porous morphology with pore sizes of several micrometers and several hundreds of micrometers respectively, equilibrium swelling ratio up to 3371% in water, tensile strength up to 0.204 MPa, and self‐healing ability. The good cytocompatibility and low toxicity of the hydrogels are demonstrated through cell culture of L929 fibroblasts in vitro experiments. The tests of hydrogels with Escherichia coli and Staphylococcus aureus reveal their antibacterial property. The results demonstrate that biocompatible anisotropic hydrogels with versatile functions could be fabricated via the rapid and energy‐saving approach of FP. [ABSTRACT FROM AUTHOR]

The pH value in the wound milieu plays a key role in cellular processes and cell cycle processes involved in the process of wound healing. Here, a microfluidic assembly technique is employed to fabricate micro‐gel ensembles that can precisely tune the pH value of wound surface and accelerate wound healing. The micro‐gel ensembles consist of poly (hydroxypropyl acrylate‐co‐acrylic acid)‐magnesium ions (poly‐(HPA‐co‐AA)‐Mg2+) gel and carboxymethyl chitosan (CMCS) gel, which can release and absorb hydrogen ion (H+) separately at different stages of healing in response to the evolution of wound microenvironment. By regulating the wound pH to affect the proliferation and migration of cell on the wound and the activity of various biological factors in the wound, the physiological processes are greatly facilitated which results in much accelerated healing of chronic wound. This work presents an effective strategy in designing wound healing materials with vast potentials for chronic wound management. [ABSTRACT FROM AUTHOR]

Nano‐/micro‐reactors have emerged as a powerful platform for chemical synthesis. Here, we develop fiber‐spinning chemistry (FSC) based on a microfluidic blow spinning (MBS) technique, allowing the availability of nanoreactors for chemical synthesis with scale‐up capacities. Proof‐of‐concept experiments focus on the utilization of MBS‐derived fibrous nanoreactors for large‐scale production of ligand‐free perovskite quantum dots (PQDs) in one step. Typically, methylammonium lead halide (MAPbX3, X=Cl, Br, and I) PQDs in situ synthesized at large scale inside polyacrylonitrile (PAN) nanofiber films (size 120 cm ×30 cm per hour), exhibit high photoluminescence (PL) quantum yield (QY) of 71 %, tunable emissive peaks (448–600 nm), and superb PL stability. The PQDs/polymer nanofiber films are potentially useful for CO2 conversion, wide‐color‐gamut displays and light‐emitting diode (LED) devices. These findings may guide the development of nano‐/micro‐reactor technology for scale‐up production of nanomaterials with various potential applications. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) present an enticing prospect for a variety of optical applications relying on their high photoluminescence (PL) quantum yield (QY). Herein, the synthesis, optical properties, structural characterizations, density‐functional theory (DFT) calculations, and potential applications of yellow‐emissive CDs (Y‐CDs) with ultra‐high PL QY are reported. Solvothermal treatment of citric acid and urea in toluene, followed by column chromatography, produces Y‐CDs exhibiting excitation‐independent PL emission at 553 nm with a high solution PL QY of 92%. A variety of optical and structural characterizations and DFT theoretical calculations are implemented to confirm the general structure and fluorescence origin of Y‐CDs, conjugated sp2‐carbon domains (fused rings) with edge groups. Significantly, transparent Y‐CDs/acrylic resin films with strong solid‐state emissions are fabricated. The Y‐CD films exhibit a high fluorescence with PL QY of 98%, good PL stability (no PL variation under continuous irradiation for 180 h), and large Stokes shift (129 nm). The potential applications of Y‐CDs for luminescent solar concentrators as well as yellow phosphors for lighting are also demonstrated. These findings thus promote the development of high‐performance CDs and their optoelectronic applications. [ABSTRACT FROM AUTHOR]

From the perspective of both fundamental and applied science, it is extremely advisable to develop a facile and feasible strategy for fabricating gels with defined structures. Herein, the authors report the rapid synthesis of patterned gels by conducting frontal polymerization (FP) at millimeter‐scale (2 mm), where a series of microchannels, including linear‐, parallel‐, divergent‐, snakelike‐, circular‐ and concentric circular channels, were used. They have investigated the effect of various factors (monomer mass ratio, channel size, initiator concentration, and solvent content) on FP at millimeter‐scale, along with the propagating rule of the front during FP in these microchannels. In addition, we developed a new microfluidic‐assisted FP (MFP) strategy by combining the FP and microfluidic technique. Interestingly, the MFP can realize the production of hollow‐structured gel in a rapid and continuous fashion, which have never been reported. Our work not only offers an effective pathway towards patterned gels by the microchannel‐conformal FP, but also gives new insight into the continuous production of hollow‐structured materials. Such a method will be beneficial for fabricating vessel and scaffold materials in a flexible, easy‐to‐perform, time and energy saving way. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CDs) have inspired vast interest because of their excellent photoluminescence (PL) performances and their promising applications in optoelectronic, biomedical, and sensing fields. The development of effective approaches for the large‐scale production of CDs may greatly promote the further advancement of their practical applications. In this Minireview, the newly emerging methods for the large‐scale production of CDs are summarized, such as microwave, ultrasonic, plasma, magnetic hyperthermia, and microfluidic techniques. The use of the available strategies for constructing CD/polymer composites with intriguing solid‐state PL is then described. Particularly, the multiple roles of CDs are emphasized, including as fillers, monomers, and initiators. Moreover, typical applications of CD/polymer composites in light‐emitting diodes, fluorescent printing, and biomedicine are outlined. Finally, we discuss current problems and speculate on their future development. [ABSTRACT FROM AUTHOR]

Photonic crystals (PCs) have been widely applied in optical, energy, and biological fields owing to their periodic crystal structure. However, the major challenges are easy cracking and poor structural color, seriously hindering their practical applications. Now, hydrophobic poly(tert‐butyl acrylate) (P(t‐BA)) PCs have been developed with relatively lower glass transition temperature (Tg), large crack‐free area, excellent hydrophobic properties, and brilliant structure color. This method based on hydrophobic groups (tertiary butyl groups) provides a reference for designing new kinds of PCs via the monomers with relatively lower Tg. Moreover, the P(t‐BA) PCs film were applied as the photoluminescence (PL) enhanced film to enhance the PL intensity of CdSe@ZnS QDs by 10‐fold in a liquid‐crystal display (LCD) device. The new‐type hydrophobic force assembled PCs may open an innovative avenue toward new‐generation energy‐saving devices. [ABSTRACT FROM AUTHOR]

ABSTRACT: Frontal polymerization (FP) is applied for the synthesis of β‐cyclodextrin/poly(vinylimidazole‐co‐N‐vinylcaprolactam‐co‐acrylic acid) (β‐CD/P(VI‐co‐NVCL‐co‐AA)) copolymers. The dependence of frontal velocity and temperature on the initiator and cross‐linker are discussed. The synthesized copolymers have been characterized by Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The thermo‐pH dual‐stimuli responsive behavior of the hydrogel is determined by swelling measurement at different temperatures and pH values. Besides, the hydrogels show intrinsic self‐healing behavior and their healing efficiency is determined by the mechanical tests. Interestingly, we integrate FP with microfluidic technology, which may realize the execution of FP under continuous condition. Such simple microfluidics‐FP integrated approach has both methodological and practical value for the synthesis of functional materials. This paper mainly presents the synthesis and characterization of β‐cyclodextrin/poly(vinylimidazole‐co‐N‐vinylcaprolactam‐co‐acrylic acid) (β‐CD/P(VI‐co‐NVCL‐co‐AA)) copolymers by using thermal frontal polymerization (TFP). Hydrogels were found to be self‐healing with good mechanical performance and show dual thermo‐pH responsive behavior. Low‐cost, energy‐saving and efficient method of thermal frontal polymerization process was integrated with microfluidics technology to prepare supraball hydrogel. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1412–1423 [ABSTRACT FROM AUTHOR]

Abstract: The large‐scale fabrication of the flexible fiber‐shaped micro‐supercapacitors has received major attention from both industrial and academic researchers. Herein, conductive and robust polyaniline‐wrapped multiwall carbon tubes reduced graphene oxide/thermoplastic polyurethane (PANI/MCNTs‐rGO/TPU) composite fibers are successfully fabricated on a large scale via the combination of facile microfluidic‐spinning process and in situ polymerization of aniline. Initially, MCNTs‐rGO/TPU fibers are formed in a T‐shape microfluidic chip, relying on the fast material diffusion and exchange in the microfluidic channel. Then, PANI/MCNTs‐rGO/TPU hybrid fibers are synthesized through an in situ chemical oxidative polymerization of aniline. With the assistance of polyaniline, these PANI/MCNTs‐rGO/TPU hybrid fibers exhibit enhanced electrochemical properties in comparison with pure MCNTs‐rGO/TPU fibers, especially in high specific capacitance, which is dramatically increased from 42.1 to 155.5 mF cm−2. Moreover, the PANI/MCNTs‐rGO/TPU hybrid fibers can endure various blending stresses, contributing to its outperforming flexibility and weavability. The best of the excellent electrochemical and mechanical properties of these conductive fibers is made to construct the flexible supercapacitors and various complicated functional fabrics. [ABSTRACT FROM AUTHOR]

ABSTRACT Infrared laser-ignited horizontal frontal polymerization is applied for the synthesis of unsaturated polyester resin (UPER) by copolymerizing unsaturated polyester with styrene (St), methyl methacrylate (MMA), and 2-dimethylamino ethyl methacrylate (DMAEMA) monomers. Dependence of frontal velocity and temperature on the initiator and monomer concentration is discussed for St-based UPER. These resins have also been characterized by Fourier transform infrared, thermogravimetric analysis, and scanning electron microscopy. The results reveal St-based resins have superior crosslinked networks. Besides, the thermo-pH responsiveness behaviors of DMAEMA-based resins are demonstrated by swelling measurements under the conditions of different temperatures and pH values. Moreover, by introducing CdSe@ZnS quantum dots and CsPbBr3 perovskites into St- and MMA-based resins, respectively, we realize the in situ generation of CdSe@ZnS-UPER and CsPbBr3-UPER composites with good fluorescence properties and fluorescent stability, which have potential application in optoelectronic devices such as light-emitting diode and perovskite solar cells. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45935. [ABSTRACT FROM AUTHOR]

Fiber-shaped micro-supercapacitors (micro-SCs) have attracted enormous interest in wearable electronics due to high flexibility and weavability. However, they usually present a low energy density because of inhomogeneity and less pores. Here, we demonstrate a microfluidic-directed strategy to synthesize homogeneous nitrogen-doped porous graphene fibers. The porous fibers-based micro-SCs utilize solid-state phosphoric acid/polyvinyl alcohol (H3PO4/PVA) and 1-ethyl-3-methylimidazolium tetrafluoroborate/ poly(vinylidenefluoride-co-hexafluoropropylene) (EMIBF4/PVDF-HFP) electrolytes, which show significant improvements in electrochemical performances. Ultralarge capacitance (1132 mF cm-2), high cycling-stability, and long-term bending-durability are achieved based on H3PO4/PVA. Additionally, high energy densities of 95.7-46.9 µWh cm-2 at power densities of 1.5-15 W cm-2 are obtained in EMIBF4/PVDF-HFP. The key to higher performances stems from microfluidic-controlled fibers with a uniformly porous network, large specific surface area (388.6 m#178; g-1), optimal pyridinic nitrogen (2.44%), and high electric conductivity (30785 S m-1) for faster ion diffusion and flooding accommodation. By taking advantage of these remarkable merits, this study integrates micro-SCs into flexible and fabric substrates to power audio--visual electronics. The main aim is to clarify the important role of microfluidic techniques toward the architecture of electrodes and promote development of wearable electronics. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of the self-healing gels facilely fabricated by VI (N-vinyl imidazole) and MAH-β-CD (β-cyclodextrin grafted vinyl carboxylic acid groups) via bottom-ignited frontal polymerization (BIFP) initiated by magnetocaloric effect. Once ignited the bottom phase, the heat upward propagates to generate the 'front' in the upper phase. Then, no further energy is added to maintain the reaction and the whole polymerization process experiences within minutes. In this system, the dependence of frontal velocity and temperature, along with morphology, swelling capacity, mechanical property, and self-healing efficiency, on the preparation parameters is investigated. Interestingly, the gels show good swelling capacity in the organic solvent, comparatively almost no absorption in water. Moreover, the as-prepared gels exhibit excellent auto-healing properties without any external stimuli at ambient temperature. The healed sample possesses 97% recovery of its tensile strength after 8 h healing time, which relies largely on the host-guest interaction between VI and MAH-β-CD. The results demonstrate that FP can be utilized as an efficient and energy-saving method to synthesize self-healing supramolecular gels. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2585-2593 [ABSTRACT FROM AUTHOR]

The ability to fabricate high-quality colloidal photonic crystal (CPC) films in large areas is critical in many applications, ranging from flexible displays, security devices to optical enhancement. Herein, a large-scaled CPC film with crack-free structure and uniform optical performance is prepared via a hydrogen-bond-assisted method. The crack-free CPC film is ascribed to the intermolecular hydrogen bonds between carboxyl (COOH) moieties of poly(styrene-methyl methacrylate acrylic acid) microspheres and isocyanate (NCO) moieties of polyurethane. Furthermore, the as-prepared CPC film is applied as a Bragg reflection mirror for fluorescence enhancement. It is demonstrated that a fourfold enhancement of fluorescence signal is achieved when the stopband of CPCs overlaps with the emission wavelength of quantum dots. This simple method of preparing large-area and crack-free CPC film is promising for developing efficient optical devices. [ABSTRACT FROM AUTHOR]

The construction of high-quality 3D polymeric photonic crystal (PC) films featuring fascinating tunable optical properties in a facile and time-efficient way remains a major concern. Herein, the rapid assembly of highly crystallized brilliant flexible 3D polymeric PC films and their application for multiresponsive colorimetric sensing are demonstrated. Monochromatic PC films with remarkably distinct structural color, narrow half-band width (27 nm), and broad tunability of band-gaps (from blue to red) are generated within seconds from highly concentrated and charged colloids (51 vol%, −57.6 mV) embedded in poly( N-isopropylacrylamide) matrix. A repulsion-induced precipitation assembly is found to be responsible for the ultrafast formation of close-packed PC colloidal arrays. Besides, the resultant PC films exhibit ultrasensitive and fast response to external stimuli, revealed by interesting droplet diffusion experiments. Thus these PC films can serve as efficient colorimetric sensing materials to visually determine diverse species including trace ionic strength (2.9 ppm), minor surfactant (1 × 10−3 m), alcohol, and pH variation (1.0-13.9). [ABSTRACT FROM AUTHOR]

The intrinsic low quantum yield (QY) of type II core shell quantum dots (QDs) composes the limitation for these heterostructured nanomaterials to be used in practical application. Herein, magnetic hyperthermia method is employed to intensify reaction process and facilely synthesize CdTe/CdSe heterostructured QDs with improved optical performance for the first time. The QY of the type II QDs is increased to 49% by further growing an inert ZnO layer. The type I interface between CdSe and ZnO helps confine electrons to the inner structure of the QDs, thus improving the QY. The successful preparation and performance enhancement of the CdTe/CdSe type II QDs via magnetic hyperthermia method demonstrate the great potential of this method for the preparation of other materials. Besides, the red-emission QDs are used as conversion materials in white light emitting diodes to reveal their promising application in practical illumination. [ABSTRACT FROM AUTHOR]

ABSTRACT Autonomous mechanical mass transportation for cargos on the microscale with no need of continuous external powering is of great scientific and technological interest due to their extensive applications. However, it is still challenging to create a self-driven system applicable to diverse micromaterial transportation demands. In this work, we developed a novel autonomous conveyer gel driven by frontal polymerization (FP). The chemical wave produced in FP was stable, and self-propagating with a constant velocity, which can be easily monitored by thermal imaging or fluorescence labeling. We investigated the influence of the initiation temperature, swelling ratio of the gel substrate, and the size of the cargos on the motion of driven behavior. Results showed that the driving velocity can be well controlled by altering the initiation temperatures of FP. The swelling ratio and the size of the cargos had a key impact on the feasibility of self-driven behavior. In addition, powerful driven capability by FP was demonstrated by successfully transporting cargos in series, and further applied for targeted synthesis of CdS nanocrystals. The methodology developed here provides an effective way to convert chemical energy to mechanical work, and may be useful in energy conversion and utilization, mass transportation and other applications. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1323-1331 [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, poly((PMMA- b-VI)- co-AA) (MMA = methyl methacrylate; VI = 1-vinylimidazole; AA = acrylic acid) hydrogels and poly((PMMA- b-VI)- co-AA)/TPU (TPU = thermoplastic polyurethane) IPN (interpenetrating polymer networks) hydrogels have been fabricated via versatile infrared laser ignited frontal polymerization by using poly(PMMA-b-VI) macromonomer as the mononer. The frontal velocity and Tmax (the highest temperature that the laser beam detected at a fixed point) can be adjusted by varying monomer weight ratios, the concentration of BPO (BPO = benzoyl peroxide) and the amount of TPU. Moreover, the addition of TPU enhances the reactant viscosity to suppress the 'fingering' of frontal polymerization (FP) and decrease Tmax of the reaction, providing a new inert carrier (TPU) to assist FP. Through the characterization of Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and differential scanning calorimetry (DSC), the desired structure can be proved to exist in the IPN hydrogels. Furthermore, poly((PMMA- b-VI)- co-AA)/TPU IPN hydrogels possesses more excellent mechanical behaviors than hydrogels without IPN structure. Besides, the poly((PMMA- b-VI)- co-AA) hydrogels present splendid sensitive properties toward substances of different flavor including sourness (CA, citric acid or GA, gluconic acid), umami (SG, sodium glutamate), saltiness (SC, sodium chloride), sweetness (GLU, glucose), enabling their potential as artificial tongue-like sensing materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1210-1221 [ABSTRACT FROM AUTHOR]

In this work, multifunctional hydrogels with vivid color change and shrinking-swelling response to temperature, ion strength, and alternating magnetic field are fabricated via magnetic assembly. The hydrogels show gradual shift colors from yellowish green to green, cyan, blue, purple, and even reddish violet in response to temperature or ion strength. In the response process, the whole color modulation process is fully reversible and transferable along with a relative short response time. Especially, the magnetism and porous structure of the hybrid hydrogel enable it to be a potential carrier for hydrophobic molecules. Taking advantage of the magnetocaloric responsiveness, the dyed oil loaded hydrogel exhibits a controllable release behavior in each reversible shrinking-swelling cycle under an alternating magnetic field. This multi-responsive hydrogel can hold promise for practical engineering applications, including sensors, displays, and controlled release. [ABSTRACT FROM AUTHOR]

The bottleneck of large-scale production of semiconductor quantum dots (QDs) is how to solve heavy metal ions waste water and the rapid separation during industrial process. A facile strategy for fabricating CdTe@Ca(OH)2 nanocrystals exhibiting both improved photoluminescence (PL) stability and prolonged PL lifetime via an economical coprecipitating technology is reported herein. The procedure on capping CdTe QDs into Ca(OH)2 crystals can enable the products to be easily filtrating separation and the content of residual Cd2+ filtrate solution to be reached to 0.238 ppm level. Also, fluorescent rod-like heterocrystals by addition of saturated CaCl2 solution is constructed. CdTe@Ca(OH)2 nanocrystals is utilized further as phosphor powders to construct white light emitting diode (WLED). The WLED presented, here, has good photoelectric properties with color rendering index of 82.4 at 350 mA, a color temperature of 4643 k, and Commission Internationale de L'Eclairage coordinate of (0.3548, 0.3532), belonging to the white gamut, showing great potential in industrial application. © 2015 American Institute of Chemical Engineers AIChE J, 62: 580-588, 2016 [ABSTRACT FROM AUTHOR]

Anisotropic fluorescent hybrid microfibers with distinct optical properties and delicate architectures have aroused special interest because of their potential applications in tissue engineering, drug delivery, sensors, and functional textiles. Microfluidic systems have provided an ideal microreactor platform to produce anisotropic fibers due to their simplified manipulation, high efficiency, flexible controllability, and environmental-friendly chemical process. Here a novel microfiber reactor based on a microfluidic spinning technique for in situ fabrication of nanocrystals loaded anisotropic fluorescent hybrid microfibers is demonstrated. Multiple nanocrystal reactions are carried out in coaxial flow-based microdevices with different geometric features, and various nanocrystals loaded microfibers with solid, string-of-beads and Janus topographies are obtained. Moreover, the resulted anisotropic fluorescent hybrid microfibers present multiple optical signals. This strategy contributes a facile and environmental-friendly route to anisotropic fluorescent hybrid microfibers and might open a promising avenue to multiplex optical sensing materials. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, we report a versatile infrared laser ignited frontal polymerization technique for the fabrication of a series of poly(DMC- co-HPA) hydrogels (DMC = methacryloxyethyltrimethyl ammonium chloride, HPA = hydroxypropyl acrylate). Because the method is based on the exothermic reaction, no further energy is required in the reaction once it is initiated. Moreover, we have found the polymerization process is a pure frontal polymerization model without involving any other reaction process. The dependence of frontal velocity and temperature on the reaction time is thoroughly discussed. The as-prepared hydrogels are pH-responsive and their maximum equilibrium swelling ratio could reach ∼3,890%. Also, the as-prepared poly(DMC- co-HPA) hydrogels capable of adsorption/desorption switching performance can be utilized for heavy metal ion removal in wastewater treatments. Interestingly, the hydrogels can float on the water surface after intaking heavy metal ions by the combination of kerosene and polyoxyethylene sorbitan monolaurate (Tween 20) in hydrogel components, greatly enhancing treatment efficiency. We believe the method described herein to rapidly construct functional hydrogels with the ability to remove heavy metal ions may find unique applications in emergency processing of water pollution. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2085-2093 [ABSTRACT FROM AUTHOR]

Mechanochromic materials which control their color variation by straightforward effective mechanical stimuli are useful for applications including switches, display devices, and sensors. It is still challenging to create mechnochromic materials with wide‐range color tunability, fast response, and sensitivity to pressure <10 kPa. Here a facile strategy to fabricate very sensitive and reversibly mechanochromic elastic photonic hydrogels (EPHs) is demonstrated. The hydrogels exhibit reversible full‐color variation within 1 s under each compression–decompression cycle. Importantly, EPH films display versatile touch‐induced chromatic behavior even under forces below 0.5 N or pressures down to 1 kPa. Furthermore, rewritable displays on EPH films are realized by the exertion of forces without any external inks. This work may provide a new way to develop smart skin materials with integrated functions of tactile sensing and color variation, as well as touch‐based flexible displays. [ABSTRACT FROM AUTHOR]

The exploration of methods allowing chemical reactions to be carried out at ultrasmall scales is of great scientific and technological interest. We report herein a microfluidic spinning technique for the fabrication of softened-polymer microarrays for use as multidimensional microreactors and the application of these microreactors in the synthesis of fluorescent nanocrystals. Highly aligned microarrays and controlled-angle grids were readily constructed from microfluidically spun polyvinylpyrrolidone (PVP) microfibers. One-zero dimensional (1D-0D), one-one dimensional (1D-1D), and one-two dimensional (1D-2D) microreactors were then produced by the intersections between microfibers and droplets, crossed microfibers, and microfibers and a PVP film, respectively; each component can be doped with different reagents. Specific examples show that these multidimensional microreactors enable the in situ generation of fluorescent nanocrystals without ligands within minutes. [ABSTRACT FROM AUTHOR]

ABSTRACT We report the facile synthesis of poly(VI- co-MAA) superabsorbent polyampholytic hydrogels (VI = N-vinylimidazole, MAA = methacrylic acid) via plasma-ignited frontal polymerization (PIFP). On igniting the top surface of the reactants with air plasma, frontal polymerization occurred and poly(VI- co-MAA) hydrogels were obtained within minutes. The preparation parameters were investigated, along with swelling capacity, morphology, and chemical structures of poly(VI- co-MAA) hydrogels. Interestingly, the hydrogels are superabsorbent in water and show ampholytic characteristic toward pH. Moreover, the hydrogels are able to capture cationic dyes through electrostatic interaction, offering the potential for further development as dye adsorbents for water purification. In addition, nanocomposite hydrogels were obtained by embedding quantum dots (carbon dots or CdS nanocrystals) into the polymer matrix, which endows the nanocomposite hydrogels with favorable fluorescence and potential applications in bioimaging and biosensing. The results indicate that FP can be applied as an alternative means for facile synthesis of multifunctional hydrogels with additional efficiency and energy-saving. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 912-920 [ABSTRACT FROM AUTHOR]

Given the increasing environmental and energy issues, materials with the ability to repair themselves following damage are highly desirable because this self-healing property can prolong the lifespan of materials and reduce replacement costs. Host-guest assemblies are a powerful approach to create supramolecular materials with versatile functions. Here, a new mode of radical polymerization is demonstrated which is achieved via magnetocaloric effect to fabricate novel host-guest supramolecular gels within 5 min. The resulting gels can repair themselves spontaneously when damaged, without the assistance of any external stimuli, and possess great mechanical strength. Moreover, the Fe3O4-doped supramolecular gels show accelerated self-healing (from 24 h to 3 h) under an applied magnetic field, which is attributed to the synergy between host-guest healing and a magnetocaloric effect. This strategy might open a promising avenue for accelerating the use of host-guest assemblies to rapidly build robust materials. [ABSTRACT FROM AUTHOR]

We describe a facile fabrication of white light-emitting cadmium sulfide (CdS)-poly(HEA- co-NVK) nanocomposites [2-hydroxyethyl acrylate (HEA) and N-vinylcarbazole (NVK)] via plasma-ignited frontal polymerization (PIFP), a novel and rapid reaction mode of converting monomers into polymers in minutes. Frontal polymerization was initiated by igniting the upper side of the reactant with plasma. Once initiated, no additional energy was required for the polymerization to occur. The chemical functional groups of the as-prepared nanocomposites were thoroughly investigated using Fourier transform infrared spectra. The dependence of the front velocity and front temperature on the initiator concentration and weight ratios of HEA/NVK was also investigated in detail. Perhaps more interestingly, the white light-emitting materials synthesized by ingeniously incorporating the compensating colors of yellow emitting from 3-(trimethoxysilyl)-1-propanethiol-capped CdS nanocrystals and blue emitting from carbazole-containing polymer were conveniently applied onto a commercial UV light-emitting diode (LED) to generate white LEDs. The subtle change in the weight ratios of CdS/NVK can significantly impact the color hue. The white light becomes gradually colder with the increase of NVK, but becomes gradually warmer with the increase concentration of CdS nanocrystals. In a broad perspective, these white light-emitting materials designed by PIFP approach will open a new pathway to develop 'QD-polymer nanocomposite down-conversion LED' in a fast and efficient way. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Atmospheric air plasma was created and applied in the frontal polymerization (FP) of fabricating poly(HPA- co-VeoVa 10) amphiphilic gels (HPA = 2-hydroxypropyl acrylate, VeoVa 10 = vinyl versatate) with enhanced physicochemical properties. In plasma-ignited frontal polymerization (PIFP), once ignited by air plasma, no further energy or treatment was required for the following polymerization. In this system, the comparison between PIFP and thermal frontal polymerization (TFP) was conducted and observed that PIFP and TFP differ considerably in terms of swelling capacity, morphology and component distribution of the products. This finding is of great importance that the simultaneous generation of active radicals in the initial stage can spread throughout reactant and anchor on the synthetic polymer with the assistance of FP. More interestingly, the PIFP-synthesized copolymer possesses remarkable selective absorption towards organic solvents, which can be facilely manipulated by varying the weight ratios of HPA/VeoVa 10. Obviously, these polymer products could serve as an 'organic solvent scavenger' in the field of industrial wastewater treatment. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

In this work, a dually sensitive colloidal crystal (CC)-loaded hydrogel has been synthesized via frontal polymerization (FP) in a facile and rapid way. First, a polystyrene CC film was fabricated by vertical deposition on the inner wall of a test tube. Then, a mixture of acrylic acid (AAc), 2-hydroxyethyl methacrylate (HEMA), and glycerol along with the initiator and crosslinker was added to this test tube to carry out FP, resulting in the formation of CC-loaded hydrogel. The influence of the mass ratios of HEMA/AAc on front velocity and temperatures were studied. The swelling behavior, the morphology, and the stimuli-responsive behavior of the CC-loaded hydrogels prepared via FP were thoroughly investigated on the basis of swelling measurement, scanning electron microscopy, and reflection spectra. Results show that the as-prepared CC-loaded hydrogels exhibit excellent dual sensitivity to both methanol concentrations and pH values with very short response time, which can be observed visually without the aid of instruments. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

All‐inorganic halide perovskite nanocrystals (PNCs) have drawn increasing attention owing to their splendid optical properties. However, such nanomaterials suffer from intrinsic instability, greatly limiting their practical application. Meanwhile, environmental regulation has restricted the emissions of volatile organic compounds (VOCs), initiating a search for alternative approaches to PNC synthesis and film forming. Herein, fiber‐spinning chemistry (FSC) is proposed for easy‐to‐perform synthesis of highly stable PNC fibrous films. The FSC process utilizes spinning fibers as reactors, reducing the generation of VOCs. This method enables the fabrication of CsPbX3 (X = Cl, Br, I) PNCs/poly(methyl methacrylate)/thermoplastic polyurethanes fibrous films at room temperature in one step, exhibiting tunable emission between 450 and 660 nm. Significantly, the in situ generation of PNCs in hydrophobic core–shell nanofibers results in highly improved fluorescence stability. PNCs/polymer fibrous films keep constant in photoluminescence (PL) after storage at atmosphere for 90 d and retain 82% PL after water immersion for 120 h (vs fluorescence quenching in 10 d in air or 5 h in water for pristine PNCs). The PNCs/polymer fibrous films endowed with superior optical stability and great flexibility show promising potentials in flexible optoelectronic applications. This work paves a facile way toward high‐performance nanoparticles/polymer fibrous films. [ABSTRACT FROM AUTHOR]

Sex pheromones, which consist of multiple components in specific ratios promote intraspecific sexual communications of insects. Plutella xylostella (L.) is a worldwide pest of cruciferous vegetables, the mating behavior of which is highly dependent on its olfactory system. Long trichoid sensilla on male antennae are the main olfactory sensilla that can sense sex pheromones. However, the underlying mechanisms remain unclear. In this study, 3 sex pheromone components from sex pheromone gland secretions of P. xylostella female adults were identified as Z11‐16:Ald, Z11‐16:Ac, and Z11‐16:OH in a ratio of 9.4 : 100 : 17 using gas chromatography – mass spectrometry and gas chromatography with electroantennographic detection. Electrophysiological responses of 581 and 385 long trichoid sensilla of male adults and female adults, respectively, to the 3 components were measured by single sensillum recording. Hierarchical clustering analysis showed that the long trichoid sensilla were of 6 different types. In the male antennae, 52.32%, 5.51%, and 1.89% of the sensilla responded to Z11‐16:Ald, Z11‐16:Ac, and Z11‐16:OH, which are named as A type, B type, and C type sensilla, respectively; 2.93% named as D type sensilla responded to both Z11‐16:Ald and Z11‐16:Ac, and 0.34% named as E type sensilla were sensitive to both Z11‐16:Ald and Z11‐16:OH. In the female antennae, only 7.53% of long trichoid sensilla responded to the sex pheromone components, A type sensilla were 3.64%, B type and C type sensilla were both 0.52%, D type sensilla were 1.30%, and 1.56% of the sensilla responded to all 3 components, which were named as F type sensilla. The responding long trichoid sensilla were located from the base to the terminal of the male antennae and from the base to the middle of the female antennae. The pheromone mixture (Z11‐16:Ald : Z11‐16:Ac : Z11‐16:OH = 9.4 : 100 : 17) had a weakly repellent effect on female adults of P. xylostella. Our results lay the foundation for further studies on sex pheromone communications in P. xylostella. [ABSTRACT FROM AUTHOR]

A fiber microreactor is constructed based on a microfluidic spinning technique on page 7253 by S.Chen, A. J. Ryan, and co‐workers, for the in‐situ fabrication of nanocrystal‐loaded anisotropic fluorescent hybrid microfibers. By designing co‐axial‐flow microdevices with different geometric features, multiple nanocrystal reactions in result in microfibers with delicate bead‐shapes and Janus microstructures, capable of multiplexed optical signals. This work develops a facile platform for rapid fabrication of anisotropic fluorescent hybrid microfibers. [ABSTRACT FROM AUTHOR]

On page 1235, C. Yu, C.‐F. Wang, and S. Chen develop a new mode of radical polymerization, namely magnetically induced frontal polymerization (MIFP), to fabricate a novel host‐guest supramolecular Gels within 5 min. The as‐prepared host‐guest supramolecular gels have remarkably great mechanical strength, as well as an intrinsic autonomic healing capability, which can further be controlled by an external magnetic field. This work develops a new platform for the rapid fabrication of diverse polymers for extensive applications. [ABSTRACT FROM AUTHOR]