Search

Thermosetting polyimide (PI) foams (PIFs) are usually synthesized through chemical foaming; however, this approach is environmentally toxic, and it is difficult to regulate the cell structure, remold the foam, and increase the foam compressive strength. The development of microcellular PIFs with ultrahigh compressive strength and high volume expansion ratio remains a challenge. Herein, thermoplastic PI with a branched structure and flexible ether bonds was synthesized through solution polymerization, and microcellular thermoplastic PIFs (TPIFs) with ultrahigh strength were fabricated via supercritical-carbon-dioxide foaming using 2,4,6-triamino pyrimidine (TAP) as a chain-extender monomer. Subsequently, a lattice model of a closed tetrakaidecahedral cell was used to clarify the relation between the foam compressive strength and polymer cell structure. Experimental results indicate that the optimal thermal imidization temperature is 230 °C and that the resulting branched structure considerably improves viscoelasticity, flame retardancy, and foaming performance. A TAP content of 0.75 g results in branched-structure TPIFs with a mean cell size of 16.8 μm. Notably, at high temperatures and pressures, the compressive strength of TPIFs with 0.75 g TAP is more than nine times of that of TPIFs without TAP. Increasing the TAP content beyond 0.75 g results in a crosslinked structure. Backward differentiation shows that TPIF compression is constant at 0.14–0.18 in the [0,0,1] lattice direction. The proposed physical foaming method is environment-friendly and can sustainably produce TPIFs with a high volume expansion ratio, an adjustable microcellular structure, and outstanding mechanical properties. [Display omitted] • Branched thermoplastic polyimide (TPI) synthesized via solution polymerization. • TPI offers superb flame resistance and recyclability for fireproofing. • Microcellular TPI foams are fabricated by supercritical CO 2 foaming. • TPI foams exhibit uniform structure and strong compressive strength. • Lattice model clarifiies the relationship between compressive strength and polymer cell structure. [ABSTRACT FROM AUTHOR]

Abstract The relationship between the macroscopic non-linear mechanics and the microscopic crystal structural evolution of pre-oriented high-density polyethylene (HDPE) is investigated by in situ synchrotron radiation wide-angle X-ray diffraction (WAXD) measurement over a wide temperature range from −10 to 130 °C. With the concept of stress-induced disordering of crystal, the ratio ( φ a / b ) of lattice parameters a to b is defined as a new structural variable, which can reflect the lattice distortion and then the microscopic stress state of orthorhombic crystal (O-crystal). According to the temperature-dependent non-linear variation of φ a / b with strain, the contributions of O-crystal and monoclinic crystal (M-crystal) to the macroscopic mechanics including linear elasticity, yielding, stress softening and strain hardening are clarified. It is found that M-crystal bears the main extensional stress once formed, although it survives within a limited strain window relying on temperature. By further combining the extensional phase diagram constructed in strain-temperature space, the HDPE deformation is recognized to undergo successively one-dimensional (1D) chain segments rotation of crystal, two-dimensional (2D) crystal plan shearing or slipping and three-dimensional (3D) recrystallization along with increasing strain or stress, demonstrating a multiscale structural transition and energy dissipation mechanism. Graphical abstract Image 1 Highlights • A new structural parameter is defined to characterize the lattice distortion and the microscopic stress state of crystal. • Multiscale structural evolutions of crystal are connected to the macroscopic non-linear mechanics of HDPE under deformation. • The research method can be generalized to other semicrystalline polymers to understand the structure-mechanics relationship. [ABSTRACT FROM AUTHOR]

Abstract Given the advantages of polyethyleneimine (PEI) for interface modification of carbon fiber reinforced polyamide 66 composite (CF/PA66), an effective method was developed to fabricate CNT@PEI-CF. The XPS results confirmed CNT@PEI-CF was covered with a double grafted layer. Interface stability investigated showed thermal stability (under injection molding temperature, about 270 °C) and structural stability of CNT@PEI-CF/PA66 interface were both improved, but PA66 crystallization behavior affected by CNT@PEI-CF was identical with that of pure PA66. The contact angle tests exhibited that its compatibility with PA66 was also enhanced. Its interfacial shear strength, composite tensile strength and elastic modulus increased by 64.74%, 27.58% and 22.68% compared with that of untreated-CFs and composite, respectively. These best mechanical properties were ascribed to the formation of "fish-scale" layers on pull-out fibers resulted from CNT@PEI-CF modification. It could be concluded that CNT@PEI-CF would not only enhance its composite mechanical properties, but also exhibit much fiber pull-out and avoid the catastrophic failure for CNT@PEI-CF/PA66 composites. This CF surface modification study would be beneficial to expand application of thermoplastic composite with reusability. [ABSTRACT FROM AUTHOR]

Achieving multifunctionality to broaden the application scenarios is the development direction of electromagnetic wave (EMW) absorbing materials in the future. Here, a waterproof magnetic carbon foam (CF) was successfully prepared using a simple high-temperature pyrolysis and dip coating process, where the magnetic Fe 3 O 4 nanoparticles were homogeneously and tightly encapsulated on the carbon skeleton of CF with the help of low surface energy PDMS, achieving the expected high-efficient EMW absorption performance. Except the 3D porous structure that contributes stronger EMW absorption through multi-reflection and scattering, the coexistence of conductive carbon skeleton and magnetic Fe 3 O 4 can supply the dielectric-magnetic dual-loss, which is also beneficial for better impedance matching. In addition, the amounts of heterointerfaces and abundant crystalline defects and doped N atoms in graphitic carbon can also generate additional polarization loss. Furthermore, high-efficient EMW absorption capacity was achieved by tuning the pyrolysis temperature, of which the CF pyrolyzed at a temperature of 900 °C (PDMS/Fe 3 O 4 /CF-900) exhibited a minimum reflection loss (RL min) value of −47.36 dB with 3.15 mm thickness and a maximum effective absorption bandwidth (EAB max) up to 9.76 GHz with 4.2 mm thickness. What's more, combining with the merits of high conductivity, hydrophobicity, and special 3D porous structure, the expected multifunctionality was also successfully achieved for the prepared PDMS/Fe 3 O 4 /CF-900, where it displays the excellent thermal management performance including a high Joule heating temperature of 161 °C at only 5 V and reliable heating capacity over 1500 s, high-efficient oil-water separation capacity such as high absorption amount (45.58 times), rapid absorption (1.14 s), and stable cyclic adsorption-desorption performances, and great thermal insulation property with a temperature difference up to 219.9 °C that make it to be promising infrared stealth material. This work provides a feasible strategy for the rational design and application of novel lightweight multifunctional high-performance EMW absorbing materials. [Display omitted] • Magnetic carbon foam was prepared for multifunctional EMW absorbing material. • The foam displays a RL min of −47.36 dB and wide EAB of 9.76 GHz. • The foam possesses great potential in the field of personal thermal management. • The foam can be applied for infrared stealth of military equipment. [ABSTRACT FROM AUTHOR]

Superhydrophobic conductive rubber band with synergistic dual conductive layer was designed and prepared for high-performance strain sensor, showing great potential for full-range monitoring of human motion and physiological signal, especially in the water environment. [Display omitted] Wearable electronic devices have received increasing interests because of their excellent flexibility, stretchability, and human friendliness. As the core components, flexible strain sensors integrated with wide working range, high sensitivity, and environment stability, especially in moisture or corrosive environments, remain a huge challenge. Herein, synergistic carbon nanotubes (CNTs)/reduced graphene oxide (rGO) dual conductive layer decorated elastic rubber band (RB) was successfully developed and treated with hydrophobic fumed silica (Hf-SiO 2) for preparing superhydrophobic strain sensor. As expected, stable entangled CNTs layer and ultrasensitive microcracked rGO layer endow the sensor with extremely low detection limit (0.1%), high sensitivity (gauge factor is 685.3 at 482% strain), wide workable strain range (0–482%), fast response/recovery (200 ms/200 ms) and favorable reliability and reproducibility over 1000 cycles. Besides, the constructed Hf-SiO 2 coating also makes the sensor exhibit excellent superhydrophobicity, self-cleaning property, and corrosion-resistance. As a proof of concept, our prepared high-performance strain sensor can realize the full-range monitoring of human motions and physiological signals even in the water environment, including pulse, vocalization, joint bending, running, and gesture recognition. Interestingly, it can also be knitted into a tactile electronic textile for spatial pressure distribution measurement. Thus, this study provides a universal technique for the preparation of high-performance strain sensors with great potential applications in the field of next-generation intelligent wearable electronics. [ABSTRACT FROM AUTHOR]

Polyimide foams (PIFs), renowned as some of the best materials for excellent performance in harsh temperature environments, have been developed to meet the increasing demands of high-tech industries. A state-of-the-art review of advanced PIFs research was conducted, covering the general research profiles and trends, institutions and scholars, major journals, research categories, and application fields through a bibliometric analysis of publications.Research on polyimide-based foam has increased approximately 30-fold over the past 40 years. One hundred forty-two research institutions from 20 countries have conducted research related to PIFs. Literature co-citation analysis reveals that the knowledge base of the PIFs research field primarily focuses on chemical synthesis foaming. This spotlight on engineering applications systematically describes the synthesis mechanisms, various typical fabrication methods, and the microstructure of PIFs. The advantages and disadvantages of this methods have been compared. Representative functions and corresponding mechanism models, which include thermal, mechanical, sensing, electromagnetic, flame retardant, oil-water separation, and other fields, have been outlined. This review offers insights into the technological development prospects and opportunities. Finally, the arduous tasks and challenges of PIFs research are summarized, providing valuable guidance for researchers interested in this field. [Display omitted] • A state-of-the-art review of PIFs research through bibliometric analysis • The synthesis mechanism, fabrication methods, and the microstructure of PIFs were systematically described. • Representative functions and the corresponding mechanism models were concluded • Provided information on the technological development prospects and opportunities • The arduous tasks and challenges of PIFs were summarized [ABSTRACT FROM AUTHOR]

Developing novel absorbent materials targeting high-efficiency, low-energy-consumption, and environmental-friendly oil spill cleanup is still a global issue. Porous absorbents endowed with self-heating function are an attractive option because of that they are able to in-situ heat crude oil and dramatically reduce oil viscosity for efficient remediation. Herein, we facilely prepared an eco-friendly multifunctional bacterial cellulose/MXene aerogel (P-SBC/MXene aerogel) for rapid oil recovery. Thanks to excellent full solar spectrum absorption (average absorbance = 96.6 %), efficient photo-thermal conversion, and superior electrical conductivity (electrical resistance = 36 Ω), P-SBC/MXene aerogel exhibited outstanding photothermal and electrothermal capabilities. Its surface temperature could quickly reach 93 °C under 1.0 kW/m2 solar irradiation and 124 °C under 3.0 V voltage respectively, enabling effective heat transfer toward spilled oil. The produced heat significantly decreased crude oil viscosity, allowing P-SBC/MXene aerogel to rapidly absorb oil. By combining solar heating and Joule heating, P-SBC/MXene aerogel connected to a pump-assisted absorption device was capable of achieving all-weather crude oil removal from seawater (crude oil flux = 630 kg m−2 h−1). More notably, P-SBC/MXene aerogel showed splendid outdoor crude oil separation performance. Based on remarkable crude oil/seawater separation ability, the versatile aerogel provides a promising way to deal with large-area oil spills. [Display omitted] [ABSTRACT FROM AUTHOR]

Manipulating the cellular microstructure is an important means to alter the mechanical properties and expand the application of polymer foams. Herein, a vacuum-counter pressure-assisted supercritical CO 2 foaming (V-CP foaming) process was developed to fabricate polypropylene (PP) foams with closed re-entrant cell structures. The re-entrant cellular structure was realized by the combined effect of the cell over expansion during the vacuum treatment stage right after the depressurization, and the rapid cell contraction under the counter pressure of the refilled air. The morphology of the re-entrant structure could be tuned by adjusting the key processing parameters. By using butanol and scCO 2 as the co-blowing agent, the over expansion and rapid contraction of cells were greatly amplified due to the plasticizing, vaporization, and liquidation of the butanol in the V-CP process. The fabricated PP re-entrant foams that have a negative Poisson's ratio possess prominent compressive properties and impact energy absorption performance. [Display omitted] • Vacuum-counter pressure-assisted scCO 2 foaming process was developed to fabricate PP foams with re-entrant cell structures. • By using butanol and scCO 2 as the blowing agent, the over expansion and rapid contraction of cells were greatly amplified. • PP re-entrant foam has a significant increase in energy absorption compared with PP conventional foam. [ABSTRACT FROM AUTHOR]

• It is a timely and comprehensive review on the quick progress of Zn anode interface. • A detailed analysis of the challenges hindering stable zinc anode interface are introduced. • Strategies to tailor Zn metal anode interface are presented. • Highly stable Zn anode interface is promising for commercial applications. In recent years, zinc metal batteries (ZMBs) have become an important alternative to lithium-ion batteries due to their high energy density, high safety, and low cost. However, the development of ZMBs still encounters several challenges such as dendrite growth, hydrogen evolution, corrosion, and passivation. These issues likely contribute to the instability of the zinc anode/electrolyte interface, hindering practical applications of zinc batteries. Recently, extensive research on the zinc anode/electrolyte interface has been conducted globally; therefore, a comprehensive review is warranted. Initially, this paper discusses the fundamentals of the zinc anode interface and the related issues arising from its intrinsic instability. Subsequently, it systematically summarizes various effective strategies for regulating the interface including zinc anode surface modification, electrolyte regulation, zinc anode structure design, and separator optimization. Finally, it concludes with a prospect on addressing challenges and providing perspectives for optimizing the zinc anode interface in order to achieve high-performance ZMBs. [ABSTRACT FROM AUTHOR]

• A conductive fiber with synergistic conductive network is prepared for strain sensor. • The synergistic effect is beneficial for tunable and balanced sensing performances. • The sensor shows great potential for human motion monitoring and tactile sensing. • The fiber displays good photothermal performances even under 150% strain. With the rapid development of portable electronic products, smart wearable devices show great application potential in personalized motion monitoring, health monitoring and even in human-machine interaction. In particular, high-performance flexible fiber-shaped strain sensors are receiving more and more attention because they can be well integrated with clothes or human skin for real-time human activities monitoring. However, achieving improved sensitivity, wide detection range, diverse applications and easy operation of them remains a challenge. Here, we adopt a simple wet-spinning technique to prepare a porous fiber-shaped carbon nanotubes (CNTs)/silver nanoparticles (AgNPs)/thermoplastic polyurethane (TPU) fiber (CATF) for high-performance strain sensor, of which the synergistic conductive network of CNTs and AgNPs enables a wide detection range (∼248 %), high sensitivity (GF > 4295), fast response/recovery time (120 ms/140 ms) and excellent stability. Interestingly, strain sensing range and sensitivity of the sensor can be tuned by changing the AgNPs loading to make it suitable for different application scenarios. All the merits of the sensor make it capable for diverse human movements monitoring, pronunciation recognition, and gesture recognition. More importantly, our prepared CATF strain sensor can be easily weaved into wearable smart textiles, showing great potential for tactile sensing to realize multi-touch and pressure tracking. Finally, the CATF also displays efficient photothermal conversion capability even under different tensile strains up to 150 %, showing great potential in human body thermal management to improve the wearing comfort of wearable electronic fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • Higher quenching temperature and longer quenching period facilitate SC crystal formation. • The addition of deionized water to the solvent effectively enhances the formation of SC crystals. • The introduction of carbon nanotubes (CNTs) as a nucleating agent significantly impacts SC crystals formation. The formation of stereo-complex crystals (SC) in porous poly (lactic acid) (PLA) material is intricately linked with improving its comprehensive properties. In this work, the effects of process conditions, solvent composition and additional nucleating agent on SC crystals during the fabrication of porous PLA through thermally-induced phase separation method were studied. Crystallization behavior of SC crystals during the pore-forming process is systematically investigated, revealing that higher quenching temperature and longer quenching period facilitate the formation of SC crystals. Additionally, the addition of deionized water to the solvent effectively enhances SC crystals formation by reducing solution viscosity and prolonging the phase separation time. The highest crystallinity of SC crystals (X SC) can be achieved, reaching 30.6%, when the water content is controlled at 1.6%. Furthermore, the introduction of carbon nanotubes (CNTs) as a nucleating agent exhibits a pronounced effect on the formation of SC crystals. When incorporating a 3 wt% content of CNTs, X SC reaches its peak value at 37.7%. This work is helpful to provide reference for improving mechanical properties and heat resistance of porous PLA, thereby expanding its potential outdoor applications. [ABSTRACT FROM AUTHOR]

Benefitting from the wearability, ductility and portability, flexible and stretchable strain sensors display a more extensive field of applications than traditional sensors in terms of medical diagnosis, smart home, environmental monitoring and so on. However, the critical sensing performances, such as sensitivity, sensing range, stability and detection limit of flexible strain sensors still need to be improved. Microstructural optimization has been considered as an efficient strategy for tuning the performances. In this work, a carbon nanotubes (CNTs)/carbon black (CB)/thermoplastic polyurethane (TPU) fibrous film (CCTF) is prepared through electrospinning, spraying and ultrasonic anchoring technique. Synergetic conductive layers by combining CNTs/CB and CB are constructed on both sides of CCTF. In virtue of the optimization of microstructures and the synergetic conductive network, the obtained CCTF possesses an ultrawide response range (up to 500 % strain), high sensitivity (gauge factor, GF up to 1516), short response/recovery time (80/80 ms), low detection limit (0.05 % strain), favorable sensing stability and long-term durability. CCTF with excellent strain sensing performances is assembled as a strain sensor, which accounts for full range human biological signal acquisition, including joint movements, muscle tension, and facial micro-expressions. This paper provides a certain reference significance for the preparation and fabrication of next-generation flexible strain sensors with high performances. A flexible strain sensor based on carbon nanotubes (CNTs)/carbon black (CB)/thermoplastic polyurethane (TPU) film (CCTF) is fabricated through electrospinning, spraying and ultrasonic anchoring technologies. CCTF possesses excellent sensing performance due to the optimization of the microstructure, achieving a wide sensing range (up to 500 % strain), high sensitivity (GF up to 1516), low detection limit (0.05 % strain), and short response/recovery time (80/80 ms). [Display omitted] • A fibrous strain sensor with synergetic conductive networks of CNTs/CB and CB is fabricated. • The sensor possesses both a wide sensing range (500 % strain) and high sensitivity (GF up to 1516). • Low detection limit (0.05 % strain) and short response/recovery time have also been achieved. • The sensor is demonstrated to precise full range human biological signal acquisition. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOF)-polymer hybrid hydrogel solves the processable forming of MOF powder and energy consumption of uranium extraction. However, the hybrid hydrogel by conventional synthesis methods inevitably lead to MOF agglomeration, poor filler-polymer interfacial compatibility and slowly adsorption. Herein, we designed that ZIF-67 was implanted into the carboxymethyl cellulose/polyacrylamide (CMC/PAM) by network-repairing strategy. The carboxyl and amino groups on the surface of CMC/PAM drive the uniform growth of ZIF-67 inside the CMC/PAM, which form an array of oriented and penetrating microchannels through coordination bonds. Our strategy eliminate the ZIF-67 agglomeration, increase the interfacial compatibility between MOF and polymer. The method also improve the free and fast diffusion of uranium in CMC/PAM/ZIF-67 hydrogel. According to the experimental, these enhancements synergistically enabled the CMC/PAM/ZIF-67 have a maximum adsorption capacity of 952 mg g−1. The adsorption process of CMC/PAM/ZIF-67 fits well with pseudo-second-order model and Langmuir isotherm. Meanwhile, the CMC/PAM/ZIF-67 maintain a high removal rate (87.3 %) and chemical stability even during ten adsorption-desorption cycles. It is worth noting that the adsorption amount of CMC/PAM/ZIF-67 in real seawater is 9.95 mg g−1 after 20 days, which is an ideal candidate adsorbent for uranium extraction from seawater. • The CMC/PAM/ZIF-67 aerogel is successfully designed via network-repairing strategy. • The CMC/PAM/ZIF-67 aerogel has a maximum adsorption capacity of 952 mg g−1 at pH = 5. • The adsorption capacity of CMC/PAM/ZIF-67 aerogel in real seawater is 9.95 mg g−1 after 20 days. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOF)-polymer hybrid hydrogel solves the processable forming of MOF powder and energy consumption of uranium extraction. However, the hybrid hydrogel by conventional synthesis methods inevitably lead to MOF agglomeration, poor filler-polymer interfacial compatibility and slowly adsorption. Herein, we designed that ZIF-67 was implanted into the carboxymethyl cellulose/polyacrylamide (CMC/PAM) by network-repairing strategy. The carboxyl and amino groups on the surface of CMC/PAM drive the uniform growth of ZIF-67 inside the CMC/PAM, which form an array of oriented and penetrating microchannels through coordination bonds. Our strategy eliminate the ZIF-67 agglomeration, increase the interfacial compatibility between MOF and polymer. The method also improve the free and fast diffusion of uranium in CMC/PAM/ZIF-67 hydrogel. According to the experimental, these enhancements synergistically enabled the CMC/PAM/ZIF-67 have a maximum adsorption capacity of 952 mg g−1. The adsorption process of CMC/PAM/ZIF-67 fits well with pseudo-second-order model and Langmuir isotherm. Meanwhile, the CMC/PAM/ZIF-67 maintain a high removal rate (87.3 %) and chemical stability even during ten adsorption-desorption cycles. It is worth noting that the adsorption amount of CMC/PAM/ZIF-67 in real seawater is 9.95 mg g−1 after 20 days, which is an ideal candidate adsorbent for uranium extraction from seawater. • The CMC/PAM/ZIF-67 aerogel is successfully designed via network-repairing strategy. • The CMC/PAM/ZIF-67 aerogel has a maximum adsorption capacity of 952 mg g−1 at pH = 5. • The adsorption capacity of CMC/PAM/ZIF-67 aerogel in real seawater is 9.95 mg g−1 after 20 days. [ABSTRACT FROM AUTHOR]

1a, the highly sensitive, thermal conductive and stretchable strain sensor consists of graphene nanoribbons (GNRs) as the conductive nanonetwork, TPU doped with BNNSs as the thermal conductive layer and TPU fibrous membrane as the thermal insulation layer, which has been fabricated by electrospinning, vacuum filtration, casting and stick. The favorable thermal conductivity of the strain sensor is attributed to that the BNNSs overlap with each other in the TPU-BNNSs film to form a perfect heat conduction pathway (Fig. In order to further understand the heat dissipation mechanism of the strain sensor, the interface heat conduction between the TPU-BNNS film and the air was simulated and calculated (Fig. [Extracted from the article]

A brief timeline summarizing the development of these strategies in hosts, artificial protection layer, and electrolyte additives. [Display omitted] Using lithium (Li) directly as metal anode for a higher energy density battery is one of the most attractive battery researches in the past decade. To address its intrinsic issues including uncontrolled growth of Li dendrites and unstable solid electrolyte interphase (SEI), which are believed as the main origins of safety issues and short lifetime, proposing the groundbreaking concepts and contributing valuable improvements in the development of Li metal anodes (LMAs) have always been the mandate of all battery scientists. This review presents a historical framework of various concepts and contributions in enabling LMAs to be applied practically. We begin with an overview of these important concepts and breakthroughs in different aspects to advance LMAs. Moreover, assisted by the big data sources from Web of Science, the major contributions from institutions, journals, corresponding authors, and highly cited papers are discussed and summarized. Finally, future trends and challenges are concluded for designing an ideal LMA. We hope that such as a comprehensive evolutionary story of LMAs can motivate more researchers to pave the way for high-energy lithium metal batteries (LMBs) in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • P-MXene@TPU monolith with aligned channels was fabricated for solar-driven absorption and recovery of crude oil. • The aligned channel structures within P-MXene@TPU monolith help reduce mass transfer hindrance, accelerate capillary force-driven absorption of crude oil, and enhance heat transfer. • P-MXene@TPU monolith exhibits stable compression property due to superelastic TPU skeleton and aligned channel structures, allowing to be suitable for multiple uses in crude oil recovery via extrusion. • The self-heating monolith under solar irradiation could continuously recover viscous crude oil from seawater via a pumping device. Cleanup of crude oil spills is challenging due to its high viscosity. Reducing the viscosity of crude oil by elevating its temperature and thus promoting absorption is considered a promising and environmentally-friendly way to address this worldwide issue. Herein, we propose a photothermal superelastic thermoplastic polyurethane (TPU)-based monolith with aligned channels successively modified with MXene and polydimethysiloxane (PDMS) (P-MXene@TPU) for crude oil absorption and recovery. The well-oriented structures help reduce mass transfer hindrance and accelerate heat transfer, while MXene and PDMS endow the monolith with excellent photothermal conversion property and hydrophobicity, respectively. P-MXene@TPU monolith demonstrates superior oil absorption performance under solar irradiation as self-heating is realized to decrease the crude oil viscosity and promote its absorption rate. Particularly noteworthy is that P-MXene@TPU monolith can bear 300 compression cycles with a deformation of 9 % owing to the superelastic TPU skeleton and aligned channels. The stable compression performance and anti-fatigue property validate that the monolith is suitable for recovering crude oil by extrusion. Continuous crude oil recovery is achieved via a pumping device and solar irradiation (1.0 kW/m2) enhances the recovery rate by a factor of 18, as compared to the one without irradiation. Given the unique structural design and exceptional properties, this monolith provides a highly efficient approach for handing the crude oil spills. [ABSTRACT FROM AUTHOR]

Nowadays, passive radiative cooling (PRC) has being attracted intensive attention because it can realize cooling effect without consuming any energy. Unfortunately, fabricating polymer film with radiative cooling effect by a facile, continuous and environmentally friendly method is still a large challenge. In this study, high density polyethylene (HDPE)/polyvinyl oxide (PEO) film were first fabricated by melt extrusion casting method, and polyethylene film composed of directional microfibrils (PFCDM) were finally obtained after selective dissolution of PEO phase in deionized water at 70 °C. The as-prepared PFCDM shows higher average solar reflectivity of 85.17% in the visible range and stronger average mid-infrared emissivity of 82.04% within the atmospheric window. It shows a sub-ambient cooling of 23.28 °C during the day and 3.1 °C at night, suggesting that it has a remarkable PRC performance. Moreover, the as-prepared PFCDM has outstanding wearability and self-cleaning property, showing promising potential of personal thermal management. This study proposes a facile but environmentally friendly method for fabricating PFCDM, paving a new way to develop wearable PRC film following the concept of thermoplastic polymers "functionalized" processing. [Display omitted] • PFCDM was efficiently prepared via melt extrusion casting and water leaching. • PFCDM shows remarkable passive radiative cooling performance. • PFCDM has higher day and night cooling power. • PFCDM has outstanding wearability and self-cleaning property. [ABSTRACT FROM AUTHOR]

Flexible transparent electromagnetic interference (EMI) shielding films in visual windows are crucial for the innovation of optoelectronic devices, but the challenge of balancing light transmittance and EMI shielding effectiveness (SE) still exists. Herein, this work described a flexible transparent MXene@SWNTs/PC film with a hierarchical conductive layer that was fabricated via an alternating rotation spraying method. The multi-scale hierarchical structure configured with 1D SWNTs and 2D MXene endow the obtained film with good comprehensive properties, i. e, low sheet resistance of 32.8 Ω/sq at 56.1% light transmittance, thus causing a satisfactory EMI SE of 20.8 dB. Moreover, the transparent shielding films exhibit remarkable flexibility, which can maintain steady EMI SE after 1000 continuous bending cycles. More importantly, the low sheet resistance and high light absorption capacity of hybrid conductive layer facilitate the transparent shielding film with low-voltage-driven electric heating effect and outstanding photothermal conversion ability, respectively, ensuring the normal operation under extreme cold condition. The combination of good light transmittance, satisfactory EMI shielding performance, and multi-source thermal response enables MXene@SWNTs/PC film to have great potential as a transparent shielding film in emerging optoelectronic devices. A multifunctional MXene@SWNTs/PC film with hierarchical structure prepared via an alternating rotation spraying process, integrating capabilities of light transmittance, EMI shielding, and multi-source thermal response together. [Display omitted] [ABSTRACT FROM AUTHOR]

Using solar energy for freshwater generation presents an effective and economical solution to address water shortages. Here, we introduced a structural strategy involving the incorporation of fixed-shape inverted pyramid-shaped grooves onto the evaporator surface. This innovation approach integrated delignified wood and MXene-based photothermal material to establish an interfacial solar steam generator (ISSG) dedicated to freshwater production. The carefully designed surface structure empowered the ISSG with remarkable heat localization capabilities, resulting in an exceptional steam generation capacity and resistance against salt deposition. The as-prepared sample, labeled MIDW-5, achieved an impressive evaporation rate of 1.927 kg m−2 h−1. Furthermore, the simulation results by COMSOL are in agreement with the experimental results. Therefore, the incorporation of MXene into delignified wood, complemented by the imprinted structure, yields a high-performance evaporator with substantial potential for low-cost freshwater production. • A MXene@wood evaporator with inverted pyramid-shaped grooves was constructed. • The evaporator has excellent thermal localization efficiency. • The evaporator shows splendid high light absorption and evaporate rate. • The evaporator is easy to prepare and environmentally friendly. • The evaporator performs outstanding desalting performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • An aligned TPU electrospun mat with wave-like structure is selected as the substrate. • The microcrack structure is constructed by pre-stretching technology. • The strain sensor can achieve sign language interpretation and multi-angle recognition. • The visual sensing function expands the application area of the CNTs/AgNWs/TPU sensor. Recently, flexible strain sensors have attracted great attention on account of the application potential in medical treatment, flexible prosthetics and human–machine interaction. Nevertheless, traditional uniaxial strain sensors cannot detect movement in different directions, limiting the applications in sensing technologies. In addition, it is still a significant challenge to simultaneously acquire visualized and high-performance strain sensors. Here, a highly flexible sensor with visual sensing function was fabricated by spraying silver nanowires (AgNWs)/carbon nanotubes (CNTs) ink on the aligned thermoplastic polyurethane (TPU) electrospun mat. The sensing performances of AgNWs/CNTs aligned TPU fluorescent mats (ACUM-F) are individually explored in vertical and parallel directions. Herein, the ACUM-F in vertical can exhibit high sensitivity (gauge factor (GF) up to 244.3), wide working range (0.1 ∼ 380 % strain), fast response/recovery time (80 ms/80 ms), good sensing durability and reproducibility (1000 stretching/releasing test cycles). Furthermore, ACUM-F is assembled as strain sensors to monitor various human body movements, which can achieve sign language interpretation through finger gesture monitoring, demonstrating its great potential in human–machine interaction. The direction-aware application of novel multidirectional sensors with visual sensing functions may bring inspiration for a new era of flexible electronics development. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) inherently shows the distinct brittleness at room temperature, which is a major drawback limiting its practical applications. Great efforts have been done to improve the toughness by adding high content of flexible polymers or low content of nanoparticles, which is often at the expense of tensile strength. In this work, supertoughened PLA blend with high elongation at break (247.7%) containing low content of poly(ethylene oxide) (PEO) (8%) was directly fabricated by melt extrusion method. Interestingly, its tensile strength and modulus are only slightly decreased (<25%). The reasons for the balanced mechanical property can be understood as follows: I) The increasing mobility of amorphous chains of PLA due to the plasticizing effect of PEO. II) The strengthening effect of mesophase can hinder tensile strength to be severely sacrificed. III) The rod-like PEO phase can initiate more crazes and further prevents them from developing into cracks, allowing effective energy dissipation. This study proposes a facile but efficient strategy to fabricate PLA blends containing low content of PEO with balanced mechanical property, which would provide a clue for toughening other brittle thermoplastics. [Display omitted] • PLA blend with balanced mechanical property is directly prepared by melt extrusion. • A low content of PEO can realize the supertoughness of PLA. • The tensile strength and modulus are only slightly decreased. • Mesophase and rod-like phase morphology are keys to supertoughness. [ABSTRACT FROM AUTHOR]

To get strong and anti-freezing hydrogel with multiple contact and non-contact sensing performance, a facial method is proposed in this work using multiple physical bonding crosslinking and glycerol (GL) immersing strategy. The obtained hydrogels show a tensile stress at break of 5.4 MPa, an elongation at break of 1420 %, and a compression strength of 12.2 MPa at 80 % strain. Additionally, benefiting from the GL immersing the hydrogel shows superior anti-freezing (no ice formation at −60 °C) and water retention ability (water loss less than 17 % after storing at 50 °C for 7 h). Furthermore, the volume resistance of hydrogels exhibits excellent responses against humidity, temperature, strain, and stress. The variation of the resistance against temperature can be well described by the Arrhenius equation with an activation energy of 501.3 meV, verifying a band-gap dominated diffusion hopping conductive mechanism of the hydrogel. The sufficient humidity and temperature responses make the hydrogel applicable as a non-contact sensor, and the wide temperature strain sensing (−40 to 50 °C) and stress sensing capability ensures that the hydrogel can be used as a contact sensor, ensuring that the hydrogel can be used as perfect flexible sensor for monitoring human motion and physiological signals. [Display omitted] • Strong and anti-freezing hydrogel with multiple sensing performance is obtained. • The hydrogel is prepared using multiple physical bonding crosslinking and glycerol immersing strategy. • The resistance variation against temperature is described by the Arrhenius equation with an activation energy of 501.3 meV. [ABSTRACT FROM AUTHOR]

Addressing water pollution issues is directly related to green sustainable development. In this work, a heterostructure polyurethane-based (PU) sponge was prepared by a facile "dip-adhere" strategy to achieve simultaneous and efficient removal of oils and dyes from water. This innovatively designed sponge comprises two functional layers. The hydrophobic/lipophilic octadecylamine-molybdenum disulfide coated PU sponge (ODA-MoS 2 @PU) layer exhibits excellent sorption capacity, ranging from 37.35 to 63.52 times its own weight, for eight organic solvents (DMSO, isopropanol, n-hexane, petroleum ether, n-butanol, glycol, acetone, xylene) and five oils (soybean oil, olive oil, gasoline, diesel, and lubrication). Furthermore, it exhibits robust stability in extreme environments and maintains a high separation efficiency (99 % after 50 separations). The photocatalytic/superhydrophilic polydopamine-molybdenum disulfide coated PU sponge (PDA-MoS 2 @PU) layer demonstrates great photocatalytic degradation efficiency for dyes (96.80 % for methylene blue and 97.39 % for methyl orange). Consequently, the heterostructure PU sponge holds application potential in environment remediation. [Display omitted] • A dual-functional heterostructure sponge was prepared. • Continuous oil-water separation was realized with the oil-gathering device. • The simultaneous treatment of removing oils and dyes was achieved. [ABSTRACT FROM AUTHOR]

Being as lightweight and thin as possible is highly desirable for electromagnetic interference (EMI) shielding materials in electronic devices as the high requirement in miniaturization and weight reduction. Constructing three-dimensional (3D) porous conductive architecture into two-dimensional (2D) film provides one of the feasible strategies. Herein, pyrolytic carbon aerogel films from aramid nanofiber (ANF) with novel skin-core structure containing compact film skin and 3D porous nanofiber network core were fabricated by a facile method. The abundant conjugate aromatic structure in backbone endows ANF-derived carbon aerogel film with a high conductivity of 1029.5 S/m. Remarkably, the high electrical conductivity, as well as the 3D porous skin-core structure, which not only constructs the interconnected electron transmission paths but also significantly extends the propagation path of EM waves, enables the carbon aerogel film a high EMI shielding effectiveness (SE) of 41.4 dB at low density (54.4 mg/cm3) and thin thickness (162 μm) with high specific shielding effectiveness (SSE/t) of up to 47122.6 dB cm2/g. Besides, ANF-derived carbon aerogel film exhibits an excellent photothermal conversion ability, which greatly broadens the application environment. More interestingly, the easy and flexible preparation method with adjustable film thickness, density and area makes large-scale production of carbon aerogel film possible. [Display omitted] • ANF-derived carbon aerogel film prepared by a facile and scalable method. • The film reveals skin-core structure with compact skin and nanofiber network core. • The carbon aerogel film exhibits high EMI SE at low density and thin thickness. • The carbon aerogel film shows an excellent photothermal conversion capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] With the rapid development of wearable intelligent devices, low-cost wearable strain sensors with high sensitivity and low detection limit are urgently demanded. Meanwhile, sensing stability of sensor in wet or corrosive environments should also be considered in practical applications. Here, superhydrophobic microcracked conductive paper-based strain sensor was fabricated by coating conductive Ti 3 C 2 T x MXene on printing paper via dip-coating process and followed by depositing superhydrophobic candle soot layer on its surface. Owing to the ultrasensitive microcrack structure in the conductive coating layer induced by the mismatch of elastic modulus and thermal expansion coefficient between conductive coating layer and paper substrate during the drying process, the prepared paper-based strain sensor exhibited a high sensitivity (gauge factor, GF = 17.4) in the strain range of 0–0.6%, ultralow detection limit (0.1% strain) and good fatigue resistance over 1000 cycles towards bending deformation. Interestingly, it was also applicable for torsion deformation detection, showing excellent torsion angle dependent, repeatable and stable sensing performances. Meanwhile, it displayed brilliant waterproof, self-cleaning and corrosion-resistant properties due to the existence of micro/nano-structured and the low surface energy candle soot layer. As a result, the prepared paper-based strain sensor can effectively monitor a series of large-scale and small-scale human motions even under water environment, showing the great promising in practical harsh outdoor environments. Importantly, it also demonstrated good applicability for spatial strain distribution detection of skin upon body movement when assembled into electronic-skin (E-skin). This study will provide great guidance for the design of next generation wearable strain sensor. [ABSTRACT FROM AUTHOR]

• A novel intercalated graphene oxide adsorbent was fabricated. • GO-pAM-MBA displays outstanding adsorption property and water-endurable. • The adsorption capacity of adsorbent from real uranium mine wastewater 5.42 mg g−1. It is a challenge to improve the adsorption performance and service life of graphene oxide (GO) composite by introducing a macromolecular to manipulate the interlayer of GO to form a good water-endurable by intercalation. By virtue of high reactivity of amino group in the cross-linked network formed by poly(acrylamide) (pAM) and N,N′-methylenebisacrylamide (MBA), the layer space of GO was manipulated to acquire more efficient uranium adsorption of GO. Furthermore, the amino group can also increase coordinative binding interactions via providing a secondary coordination sphere, which adjusts the electron density of composites to lower the overall charge on U(VI) and provides an additional point allowing hydrogen bond to align U(VI) in a satisfactory coordination style. Herein, a high adsorption capacity and water-endurable of GO-pAM-MBA was constructed by interface manipulation on GO surface. The U-uptake capacity of GO-pAM-MBA was 984.2 mg g−1 (4.14 mmol g−1) in aqueous solutions, which was 1.6 times than that of pristine GO under same environment. The resultant adsorbent achieved a high adsorption amount of 5.42 mg g−1 in real uranium mine wastewater. Furthermore, GO-pAM-MBA displayed good water-endurable even after six cycles. Overall, the adsorption performance indicated that the GO-pAM-MBA was an excellent appropriate adsorbent for extracting uranium. [ABSTRACT FROM AUTHOR]

The chemical conversion of the surface termination of 2D transition metal carbides/nitrides (MXenes) has opened up a design space that previously had not been extensively explored for this functional material. Herein, via a simple sealed thermal method, the amino terminated groups were successfully introduced on Ti 3 C 2 MXene surface. The substitution reaction of amino group to hydroxyl group was proposed to elucidate this aminated process. As the amination would reduce the carrier density on the surface of MXene, the electrical conductivity of MXene-NH 2 film decreased, while it still reached a high conductivity of 2.11 × 104 S m−1. This film also possessed an excellent electromagnetic interference shielding effectiveness of 16160 dB cm2 g−1. Importantly, although the introduction of amino termination altered Zeta potential value, Zeta potential sign remained negative and the MXene-NH 2 exhibited excellent dispersity in water similar to that of traditional MXenes. Furthermore, the existence of covalent bonds endowed MXene-NH 2 polymer composite film with improved mechanical properties. Compared with that of traditional CMC/MXene film, the tensile strength and fracture energy of CMC/MXene-NH 2 increased by 65.5% and 132.7%, respectively. These results demonstrated that the introduction of amino terminated group on MXene surface would be an effective strategy to obtain higher performance MXene-based films. [Display omitted] [ABSTRACT FROM AUTHOR]

For smart devices, there is a growing demand for multi-functional soft actuators, nevertheless, well-developed actuators always respond to single stimulus, and it is still challenging to achieve the application diversity standards. Herein, a bidirectional multi-stimuli responsive soft actuator based on Ti 3 C 2 T X MXene-cellulose nanowhiskers (CNWs)-polyvinyl alcohol (PVA)/polydimethylsiloxane (PDMS) multilayer membranes is proposed (MXCP-P). By grafting CNWs onto MXene nanosheets, a freestanding composite film with gradient layered structure was prepared. Due to the hygroscopicity among MXene nanosheets, increased interlayer space is in favor of adsorption/desorption of water molecules, causing invertible shape change and humidity-driven deformation with a rapid response. Based on high photothermal conversion capacity of MXene and large difference of coefficient of thermal expansion between PDMS and MXene, the MXCP-P achieves an ultra-large amplitude and fast response driven by natural light. A Venus flytrap soft robot is constructed with good actuation behaviors. The MXCP-P film was employed as actuators in the opera of The Male Phoenix Pursui from Han Dynasty and in shadow puppetry "Monkey King Subdus the White-Bone Demon" of China, both exhibiting excellent performances towards humidity and light stimuli synchronously. This paper inspires a new strategy for multi-stimuli responsive soft bionic robots and intelligent traditional shadow play. MXCP-P based multi-stimuli responsive flexible actuator was fabricated, showing improved mechanical properties and bidirectional bending characteristics. In addition to its application in traditional fly traps and rolling robots, the MXCP-P actuator is also employed to develop traditional Chinese opera culture, such as "The Male Phoenix Pursui" and "Shadow puppetry". [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-adhesive, self-healing and multimodal sensing organohydrogel was prepared. • Environmental stability of organohydrogel is enhanced by glycerol and PA. • The organohydrogel shows wide humidity response and temperature detection range. • The organohydrogel displays reliable strain sensing ability in a wide strain range. Conductive hydrogel (CH) has drawn widespread interest in flexible electronics, human–computer interaction, and electronic skins (e-skins). However, it is challenging to integrate satisfactory self-adhesion, self-healing, environmental stability, and multi-stimulus response into a single CH system. Herein, a conductive nanocomposite organohydrogel with the above characteristics is well-designed and developed via incorporating carboxylic cellulose nanofibers-carrying carboxylic carbon nanotubes (C-CNTs) and phytic acid (PA) into polyacrylamide network through free-radical polymerization plus glycerol solvent displacement strategy, aiming for a high-performance multimodal sensing platform. Here, the coupling of C-CNTs and ionization of PA contributes a favorable conductivity, and the coexistence of glycerol and PA is beneficial for the formation of amounts of hydrogen bonds that endow the organohydrogel with outstanding stretchability, self-healing, and favorable adhesion in a wide temperature range of −30 to 60 °C. Besides, the resultant organohydrogel can effectively detect multiple external stimuli, manifesting high strain sensitivity over a broad strain range (0–1566 %), good humidity detectability at 0–85 % RH, and reliable thermosensation capability over a wide temperature window (−30 to 60 °C). Significantly, the application of the organohydrogel as e-skins are conducted to detect full-range human activity movements even in the extreme environments, identify hand gestures, and recognize the spatial distribution of humidity in noncontact sensing. All these indicate the preponderance of our organohydrogel in the fields of flexible smart electronics. [ABSTRACT FROM AUTHOR]

• Layer-by-layer scraping can produce a powerful shearing effect for UHPE/GNPs gel. • Strong shearing induced dense stacking and ordered alignment of GNPs and PE chains. • The dense and ordered structure drastically enhanced in-plane TC up to 28.88 W/mK. • The solar-thermal conversion ability was also improved by the ordered structure. The simultaneous achievement of ordered alignment for fillers and polymer matrix is highly desired in polymer-based thermally conductive composites, but it is still extremely challenging. Herein, we put forward a layer-by-layer scraping (LbLS) method to simultaneously arrange ultra-high molecular weight polyethylene (UHPE) chains and graphene nanoplates (GNP) into a highly oriented structure. When UHPE/GNP gel suffering the strong shearing effect during LbLS process, the inner UHPE chains and GNP were dragged and orderly arranged along shearing direction, and these oriented structures were retained after rapidly drying by distillation. After layer-by-layer stacking, nacre-like UHPE/GNP films with tightly layered structure were obtained. By adjusting the scraping gap from 200 to 50 μm, the oriented structure can be effectively reinforced with the Herman orientation factors f increasing from 0.83 to 0.88 for GNP and 0.75 to 0.82 for UHPE chains. The highly ordered structure can form a tight and oriented thermal conduction network with low interfacial thermal resistance in plane. The LbLS composite film thus significantly enhanced the in-plane thermal conductivity up to 28.88 W/mK, compared with traditional solution casting film (9.63 W/mK). Moreover, the highly oriented structure can significantly increase the solar-thermal conversion performance (58.1 °C@100 mW/cm2) by improving its light absorption ability comparing to that of solution casting film. Besides, the mechanical strength and toughness that depend on the filler and chain alignment were effectively increased by the oriented structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Breathable electronic skin with 3D skeleton and microcrack structures is designed. • High sensitivity and wide working range are realized for the strain sensor. • The strain sensor can accurately distinguish various human movements. • The device has photo-thermo-electric and self-powered sensing applications. With the rapid development of wearable electronic, electronic skin with excellent performance for human motion detection have been widely investigated recently. In this work, a multifunctional electronic skin with three-dimensional conductive network skeleton was prepared based on synergistic conductive filler (carboxylated multi-walled carbon nanotubes (C-MWCNT) and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS)) decorated breathable thermoplastic polyurethane (TPU) electrospinning fibrous membrane. Then, microcrack structure was constructed via pre-stretching and the strain sensitivity of the resultant C-MWCNT/PEDOT:PSS/TPU (CPT) conductive fibrous membrane could be effectively adjusted by changing the microcrack density. Due to the three-dimensional conductive network skeleton, microcrack structure and the bridging effect of C-MWCNT between the adjacent crack fragments, ethylene glycol treated CPT (mass ratio of C-MWCNT and PEDOT:PSS is 9/1) (e-CPT 9/1) strain sensor exhibited high sensitivity (6008.3), wide response range (680 %), fast response/recovery time (200 ms/200 ms), low detection limit (0.5 %), excellent durability and repeatability (6000 cycles). The excellent strain sensing performances enables it to accurately monitor motion activities and physiological signals, and can also be used as a smart sensing glove to identify different letters gesture and numeric gestures. Furthermore, owing to the photothermal conversion ability and thermoelectric effect of C-MWCNT and PEDOT:PSS, the obtained e-CPT 9/1 device also displayed efficient "light-thermal-electric" conversion ability and showed the great potential as self-powered strain sensor. [ABSTRACT FROM AUTHOR]

Polyimide foams (PIFs) are usually synthesized by solution polymerization, followed by chemical foaming to prepare thermosetting foam. In this research, lightweight microcellular thermoplastic polyimide foams (TPIFs) were fabricated via a novel two-step foaming approach using supercritical carbon dioxide (scCO 2) as a blowing agent. The poly(amic acid) (PAA) and polyester ammonium salt (PEAS) precursor solutions were synthesized with pyromellitic dianhydride (PMDA) as dianhydride reagents and polyether amine Jeffamine D230 as aliphatic diamine reagent via blending and solution polymerization, respectively. The solution polymerization process demonstrated a higher molecular weight and superior formability than the blending process. The optimum thermal imidization temperature of 200 °C was optimized via the thermal and rheological property analysis. The cell morphology and mechanical properties of the TPIFs could be turned by varying the saturation time, foaming pressure, and imidization temperature. At a thermal imidization temperature of 200 °C, the TPIFs exhibited a branched structure with a small mean cell diameter (123.78 μm), and a high compressive strength (0.4 MPa) under 10 % strain at high temperature and pressure, which was more than ten times that of the TPIFs with thermal imidization temperature of 130 °C. This research provides a feasible method for producing high volume expansion ratio TPIFs with adjustable microcellular structures and outstanding mechanical properties. [Display omitted] • Poly(amic acid) and polyester ammonium salt precursor were synthesized by blending and solution polymerization, respectively. • Adding a flexible linkage provided the torsional capacity of the chain segment, and improved its flexibility. • Microcellular TPI foams were fabricated via a novel two-step foaming approach using supercritical CO 2 as a blowing agent. • The branched molecular structure was favourable for improving cell uniformity and mechanical properties. [ABSTRACT FROM AUTHOR]

With the rapid development of multi-function touch panels, more requirements are raised for touch screens including anti-smudge, anti-fingerprint, and high wear resistance, hardness, and UV resistance. Herein, ladder-like poly(2-(3,4-epoxycyclohexyl)ethyltrimethoxy- co -1H,1H,2H,2H-perfluorodecyltriethoxysilsesquioxane)s (LPEFSQs) were synthesized by the sol-gel reaction of 2-(3,4-Epoxycyclohexyl)ethyltrimethoxysilane (ECTMS) with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (PFDTES) to reduce the surface energy of the coating. The incorporation of fluorine chains resulted in an improvement of water contact angle from 77.1° to 115.5°, and oil contact angle from 35.4° to 94.7°, respectively. The omniphobic property rendered the coating excellent anti-smudge and anti-fingerprint properties while maintaining an extraordinary visible light transparency of 90.1 %. A proper PFDTES fraction of 5 % and the curing agent of I-250 are desired for the coating to simultaneously realize excellent pencil hardness of 6H, anti-smudge, and wear resistance performance. The optimized LPEFSQ coating could withstand a steel wool abrasion for 500 cycles. In addition, the developed LPEFSQ coating maintained excellent omniphobicity when subjected to ultraviolet (UV) irradiation for 200 h demonstrating excellent UV resistance. Therefore, this work provides insights into the synthesis of multifunctional coatings integrated with high transparency, wear resistance, and hardness as well as anti-smudge, and anti-fingerprint properties for touch screens. [Display omitted] • A ladder-like polysesquioxane coating containing long fluorine chains is developed. • The coating has high transparency, omniphobic surface, and anti-fouling properties. • The UV curing agent I-250 rendered the coating superior hardness and wear resistance. • The coating has excellent mechanical robustness, anti-fingerprint, and UV resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • • Prepared porous nanofibers via electrospinning. • • Studied co-adsorption of uranium by photocatalysts and chemical groups. • • Used MXene as a co-catalyst to improve the catalytic reaction. • • PAO/ZIF/MXene has high U-sorption capacity in real seawater (6.90 mg-U/g-Ads). The synergistic photocatalysis and adsorption of uranium(VI) (U(VI)) are promising strategies for extracting uranium from seawater. In this study, a porous polyamidoxime/zeolite imidazole framework-8/Ti 3 C 2 (PAO/ZIF/MXene) nanofiber film was prepared using electrospinning. The ZIF-8/MXene composite in PAO catalyzed the reduction of uranium under light, adsorbed uranium on the active sites of PAO, and produced reactive oxygen species to prevent unwanted bacterial adhesion on the surface. The adsorption capacity reached 740.8 mg-U/g-Ads after 10 h under simulated one-sun irradiation. The adsorption process conformed to the Langmuir adsorption isotherm and pseudo-second-order kinetic model. Moreover, the PAO/ZIF/MXene nanofibers exhibited good cyclic stability, and acid and alkaline resistance. The adsorption capacity of the adsorbent under visible light irradiation was 6.90 mg-U/g-Ads, thus exhibiting a good adsorption performance. These properties suggest that the PAO/ZIF/MXene nanofibers are promising materials for uranium extraction from seawater. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) is one of the most promising bio-based polyester with great potential to replace for the petroleum-based polymers, which can significantly reduce greenhouse gas emissions. However, the inherent brittleness of PLA seriously restricts its broad applications. Herein, PLA/poly(ε-caprolactone) (PCL)/ethylene methyl acrylate-glycidyl methacrylate (EMA-GMA) ternary blends with different phase structures were prepared through reactive blending. The reactions between the epoxy groups of EMA-GMA and the carboxyl and hydroxyl end groups of PLA and PCL and were evidenced from the Fourier transform infrared spectroscopy, dynamic mechanical analysis and rheological results. The atomic force microscopy (AFM) images clearly revealed the formation of stack structure of the PCL and EMA-GMA minor phases in PLA/PCL/EMA-GMA (80/15/5) blend, and core-shell particle structures in PLA/PCL/EMA-GMA (80/10/10) and (80/5/15) blends. In terms of elongation at break and impact toughness, PLA/PCL/EMA-GMA (80/5/15) blend presents the best properties among all the compositions. Moreover, it also behaved excellent stiffness-toughness balance. The toughening mechanism can be ascribed to the formation of core-shell structure and the existence of interfacial adhesion in the ternary blends. This work can provide guide for the preparation and design of PLA-based partially renewable supertough materials that can compete with conventional petro-derived plastics. • PLA/PCL/EMA-GMA ternary blends with different phase structures were fabricated. • Reactions of EMA-GMA with PLA and PCL were evidenced. • AFM images clearly revealed stack or core-shell structures of minor phases in PLA. • PLA/PCL/EMA-GMA (80/5/15) shows the best toughness and stiffness-toughness balance. • Core-shell structure of minor phases is mainly responsible for toughening of PLA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Degradable interfacial solar vapor generator (DISVG) was successfully fabricated. • Effective thermal localization is achieved on the DISVG by a double-layer design. • The DISVG shows an outstanding evaporation rate of 3.88 kg m-2 h−1 under 1 sun. • The DISVG shows excellent salt resistance and dye removal capacity. The interfacial solar vapor generator (ISVG) has emerged as a promising solution to address freshwater scarcity. The enhancement of thermal localization and suppression of salt crystallization are recognized as the design key factors for ISVG. In this study, we successfully fabricated a novel double-layer structure degradable interfacial solar vapor generator (DISVG) utilizing chitosan monolith (CM) with honeycomb porous morphology as carrier material, while employing MXene nano-sheets as solar absorber. The fabrication process involved facile chemical crosslinking and dip-coating methods. The incorporation of the double-layer structure in the DISVG plays a significant role in achieving effective thermal localization, thereby minimizing heat transfer to bulk water. Consequently, this feature results in a remarkable improvement in evaporation rate while simultaneously enhancing salt resistance. The DISVG demonstrated an outstanding evaporation rate of 3.88 kg m-2 h-1 under 1 sun (1 kW m-2) irradiation and effectively removed more than 99% of salt and dyes in water. Interestingly, even without the presence of MXene, the DISVG still achieved efficient evaporation at a rate of 2.63 kg m-2 h-1 under 1 sun irradiation. Moreover, both DISVGs exhibited stability over extended period of operation without any rate decay. This study not only presents a novel approach for the progress of environmentally friendly and cost-efficient ISVG but also offers valuable insights into overcoming the trade-off between thermal localization and salt resistance in such systems. [ABSTRACT FROM AUTHOR]

Personalized rehabilitation training provides maximum help to stroke patients to alleviate the after-effects and restore the body to normal function. However, available monitoring devices have the disadvantages of being large, requiring professional guidance, and lacking intuitive signal display capabilities. Herein, a bio-inspired wearable high-performance strain sensor with a simple structure can simultaneous electrical signals and optical visualization in response to external stimuli. The sensor comprises a conductive layer with significant electromechanical behaviors of cellulose nanocrystals (CNC)/carbon nanotubes (CNTs)/MXene nanohybrid network, and a stretchable elastomer layer consisting of thermoplastic polyurethane and fluorescent agent. Benefiting from the designed microcracks and fluorescent material, the strain sensor exhibits ultra-high sensitivity (476800), ultra-low detection limit (0.005%), low response time (60 ms), wide working range (0–100%), and enables strain visualization for applications in visually rehabilitation training monitoring. Based on these sensing characteristics, the sensor shows great advantages in human motion and sound monitoring, with the integration of digital signals and visual images makes it show great potential in visually personalized rehabilitation training monitoring. [Display omitted] • Cellulose nanocrystals are introduced to modulate the sensitivity of the strain sensor. • CCMTPF has ultrahigh sensitivity of 476800 and ultralow detection limit of 0.005%. • CCMTPF achieves electric signals and visualization of optical images responses under strain. • CCMTPF has been demonstrated for visual rehabilitation training monitoring in real time. [ABSTRACT FROM AUTHOR]

[Display omitted] • ANF-carbonized welding is used to reduce the ITR of 3D graphene architecture. • PCM containing graphene architecture shows a TC of 4.85 W/mK at 4.26 vol% content. • Thermal conductive architecture achieves the rapid heat transfer/storage in PCM. • Graphene architecture enables PCM solar/electric-to-thermal conversion capacity. Graphene-based porous architectures are promising in addressing the poor thermal conductivity, leakage, shape stability problems of organic phase change materials (PCMs), meanwhile endowing them with excellent solar/electric-to-heat conversion ability, but they are still limited by the high interfacial thermal/electrical resistance in architectures caused by organic "binders". In this work, in view of the excellent gel ability of aramid nanofibers (ANF) and its highly ordered conjugate molecular structure, a promising graphene porous architecture assisted by ANF was constructed by unidirectional freeze casting coupled with carbonization welding technique. Due to the similar graphite lattice structure of ANF-derived carbonization and graphene, the interfacial thermal/electrical resistance in highly vertically oriented graphene architecture was greatly reduced. As a result, the PCMs composite encapsulated by the graphene architecture carbonizing at 1500 °C exhibited an outstanding thermal conductivity of as high as 4.85 W/mK at only 4.26 vol%, which enables a rapid heat transfer and storage in PCM composite. The honeycomb porous graphene architecture with high porosity can accommodate sufficient PCMs for energy storage, showing a high latent heat enthalpy of 149.7 J/g with excellent shape stability during phase change process. More importantly, the graphene architecture endows PCM composites with excellent solar/electric-to-thermal conversion capacities, which not only expands the types of energy stored by PCMs, but is also promising in the thermal management application requiring a continuous and stable temperature environment. [ABSTRACT FROM AUTHOR]

High-toughness biodegradable poly(lactic acid) (PLA) has always been intensively pursued on the way of replacing traditional petroleum-based plastics. Regulating microstructures to achieve self-toughening holds great promise due to avoidance of incorporating other heterogeneous components. Herein, we propose a straightforward and effective way to tailor microstructures and properties of PLA through melt-stretching and quenching of slightly crosslinked samples. The melt stretching drives chains orientation and crystallization at high temperature, while the quenching followed can freeze the crystallization process to any stage. For the first time, we prepare a type of transparent and low-crystalline PLA filled with rod-like β-form shish, which displays an outstanding tensile toughness, almost 17 times that of the conventional technique-processed one. This mechanical superiority is enabled by an integration of high ductility due to oriented chain network, and high tensile stress endowed by nanofibrous filler's role of β-form shish. Furthermore, the mechanically toughened PLA is demonstrated to generate the richest micro-cracks and shear bands under loading, which can effectively dissipate the deformational energy and underlie the high toughness. This work opens a new prospect for the bottom-up design of high-performance bio-based PLA materials that are tough, ductile and transparent by precise microstructural regulation through scalable melt processing route. • Melt stretching and quenching were combined to regulate microstructures of PLA. • High-toughness PLA composed of oriented chain network and β-form shish was fabricated. • Oriented chain network provided ductility and β-form shish imparted high tensile stress. • Numerous micro-cracks and shear bands were formed in toughened PLA under tensile deformation. [ABSTRACT FROM AUTHOR]

Graphene (Gr) and its derivatives (such as graphene oxide (GO), reduced graphene oxide (RGO), nanoparticles decorated graphene, etc.) reinforced metal matrix composites (MMC) with good structural mechanical properties and functional properties have wide applications in aerospace, automotive, electronics and military fields. However, some problems exist in preparing high performance MMC including poor wettability between Gr-type fillers and metal matrix, and weak interfacial bonding strength. Efficient methods for preparing Gr-related nanomaterials filling metal matrix parts with high performance, especially for complex parts still need be further developed. The engineering application field of Gr MMC needs to be further expanded. In this paper, methods to prepare high performance MMC including surface modification of Gr and its derivatives, properties and applications of these reinforced MMC were reviewed with detailed examples. The main challenges were analyzed and the development trend of Gr-type types reinforced MMC was discussed. Image 1 • Surface modification of graphene improved wettability between graphene and metal matrix. • Methods for preparing metal matrix composites were reviewed. • Properties of graphene reinforced metal matrix composites were reviewed. • Applications of the metal based graphene composites were reviewed. [ABSTRACT FROM AUTHOR]

The knowledge about the influence of the electron beam (EB) radiation dose on the chemical and physical changes of polymers is critical either for sterilization purpose or materials modification. In this work, the effect of EB irradiation dose ranging 25–100 kGy on the properties of commercial poly(lactic acid) (PLA), poly(butylene adipate- co -terephthalate) (PBAT) and their blends was compared. The samples of about 0.5 mm in thickness were prepared by hot pressing. The changes in molecular weight, yellow index, thermal and mechanical properties were evaluated. The main findings are that a severe reduction in the glass transition and melting temperatures as well as the mechanical properties of PLA occurs when subjected to higher doses of EB irradiation, which can be ascribed to irradiation-induced decrease in molecular weight; while the effect of EB irradiation on the molecular weight and mechanical properties of PBAT and PLA/PBAT blends is ignorable. [ABSTRACT FROM AUTHOR]

With the rapid development of smart wearable devices, flexible and biodegradable sensors are in urgent needs. In this study, "green" electrically conductive Ag nanowire (AgNW)/cellulose nanofiber (CNF) hybrid nanopaper was fabricated to prepare flexible sensors using the facial solution blending and vacuum filtration technique. The amphiphilic property of cellulose is beneficial for the homogeneous dispersion of AgNW to construct effective electrically conductive networks. Two different types of strain sensors were designed to study their applications in strain sensing. One was the tensile strain sensor where the hybrid nanopaper was sandwiched between two thermoplastic polyurethane (TPU) films through hot compression, and special micro-crack structure was constructed through the pre-strain process to enhance the sensitivity. Interestingly, typical pre-strain dependent strain sensing behavior was observed due to different crack densities constructed under different pre-strains. As a result, it exhibited an ultralow detection limit as low as 0.2%, good reproducibility under different strains and excellent stability and durability during 500 cycles (1% strain, 0.5 mm/min). The other was the bending strain sensor where the hybrid nanopaper was adhered onto TPU film, showing stable and recoverable linearly sensing behavior towards two different bending modes (tension and compression). Importantly, the bending sensor displayed great potential for human motion and physiological signal detection. Furthermore, the hybrid nanopaper also exhibited stable and reproducible negative temperature sensing behavior when it was served as a temperature sensor. This study provides a guideline for fabricating flexible and biodegradable sensors. [ABSTRACT FROM AUTHOR]

Poly(ε-caprolactone)/poly(lactic acid) (PCL/PLA) blends are promising biomaterials with biodegradable characteristics. However, poor compatibility of the two components may lead to undesirable mechanical properties. In this work, the effect of combining carboxyl multi-walled carbon nanotubes (CNTs) and organically modified montmorillonite (MMT) on the morphology and properties of PCL/PLA blend was investigated. The morphological observations and rheological analysis showed that exfoliated MMT platelets enhanced interfacial adhesion of the two phases, whereas CNTs formed a percolating network in PCL matrix. The addition of CNTs/MMT (0.5 wt%: 0.5 wt%) led to an increase by 137.4% in elongation at break, 79.6% in tensile strength, and 14 °C in decomposition temperature without sacrificing its rigidity apparently for the PCL/PLA matrix. Obvious synergistic effect was demonstrated in comparison to the blends containing single nanofiller. This study demonstrated that combining CNTs and MMT is a facile way to preparing immiscible PCL/PLA blends based nanocomposites with interesting structure and properties. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biodegradable and biocompatible polyester derived from renewable resources like corn starch, presenting great potential in clinical applications like tissue engineering, implants and drug delivery systems. However, the intrinsic brittleness restricts its real applications. In this work, PLA nanocomposites were prepared by incorporating a small amount of carboxyl functionalized multi-walled carbon nanotubes (CNTs) and surface compatabilized montmorillonite (MMT) via technologies of freeze-drying and masterbatch-based melt blending. In the resulting nanocomposites, a well-distributed nano-filler network with microstructures of 1-D CNTs/2-D MMT platelets is formed favored by the enhanced interfacial interaction between the organic modified fillers with PLA matrix. Thanks to the well dispersed organic modified nanofillers, a large number of microcracks and extremely stretched PLA matrix are induced during tensile process, dissipating amounts of energy. As a result, the filler networks reinforce PLA with increment of 19% in modulus, remarkably increase by 13.8 times in toughness relative to PLA control without sacrificing strength. Thus, the PLA nanocomposites with excellent properties prepared through the facile and effective route possess broad prospect in biomedical applications. [ABSTRACT FROM AUTHOR]

Excess sludge, a carbon-rich valuable by-product from wastewater treatment, is utilized as a carbon precursor for synthesizing porous activated carbon. However, improving specific surface area (S BET) is the main challenge for the sludge derived activated carbon (SAC). In this study, the carbonization process was optimized as following: carbonization temperature of 900 °C, heating rate of 10 °C/min, and dwell time of 30 min. Moreover, the residue heavy metals and bound water remaining in the sludge were demonstrated to be important in the pore formation of the SAC. The metals acted as hard template to form the pores in the SAC after the metals were removed by acid wash. The bound water was found to be soft templates for forming pores due to its evaporation during carbonization. A maximum S BET of 1018.8 m2/g was achieved for the SAC when the bound water content was controlled at 2 wt%. Image 1 [ABSTRACT FROM AUTHOR]

• Freeze-dried PEO/GNP masterbatch was melt-mixed with PLA and PBAT. • Adding 1 wt% PEO reduces greatly the complex viscosity of the nanocomposites. • PEO effectively promotes the dispersion of GNP in dispersed PBAT phase. • PEO greatly enhances the toughness and thermal stability of PLA/PBAT/GNP. • Effect of the molecular weight of PEO was evaluated. Graphene nanoplatelets (GNP) is a relative new nanofiller used to tailor the morphology and properties of immiscible polymer blends. However, the self-agglomeration of GNP in the polymer matrix prevents the improvement in mechanical properties. In this work, a water-soluble polymer, poly(ethylene oxide) (PEO), was introduced to improve the dispersion of GNP in biodegradable immiscible poly(lactic acid) (PLA)/poly(butylene adipate- co -terephthalate) (PBAT) blends. PLA/PBAT based nanocomposites were prepared by melt-mixing PLA and PBAT with freeze-dried PEO/GNP masterbatch. It is found that a small amount of PEO incorporation (1 wt%) enhances the dispersion of GNP in the dispersed PBAT phase and reduces the complex viscosity of the systems significantly. Moreover, the presence of PEO enhances greatly the toughness and thermal stability of PLA/PBAT/GNP nanocomposites. The effect of the molecular weight of PEO was also addressed. [ABSTRACT FROM AUTHOR]