最新刊期
卷 55 ， 期 6 ， 2024
- 摘要：Today is an intelligent era with the rapid development of the Internet of Things (IoT), and novel human-machine interface (HMI) devices will greatly change people's lives. Devices based on silicon/metal materials can hardly meet the requirements of seamless integration for the long-term and stable interface, while optoelectronic polymer materials are becoming an ideal choice due to their lower Young's modulus and better intrinsic tensile properties. However, there are still challenges to achieving both efficient carrier transport and sufficient ductility in material design. This feature article discusses the innovations in devices for power supply, sensing, neural interface, display, and integrated HMI systems. It then analyzes the bottlenecks faced in terms of materials, devices, and integration. We also provide an outlook on the applications and prospects for HMI technologies. These devices include intrinsically stretchable organic solar cells (OSCs), organic thermoelectric generators (oTEGs), ion batteries, nanogenerators (NGs) and supercapacitors (SCs). They are ideal off-grid power sources for human-machine interface devices. Additionally, there are intrinsically stretchable organic photodetectors (OPDs), chemosensors, and thermosensors, which are ideal for light, chemical, and thermal sensing devices. Furthermore, there are intrinsically stretchable polymer multielectrodes arrays (MEAs) and organic electrochemical transistors (OECTs), which are ideal for detecting and transmitting electrical and electrophysiological signals, respectively. Then there are integrated display devices with excellent performance, including organic light-emitting electrochemical cells (OLECs/OLEECs), organic electrochromic displays (OECDs), organic light-emitting diodes (OLEDs). Finaly, there are organic field effect transistors (OFETs), which are the basic components of organic integrated circuits. It shows that enhancement of the optoelectronic performance of stretchable conjugated polymers, and reliable interfaces between functional layers are the focus of future studies.关键词：Human-machine interface;Optoelectronic polymer materials;Optoelectronic devices;Intrinsic stretchability
- 967
- |
- 387
- |
- 0
发布时间：2024-06-05
Feature Article
- 摘要：Hydrogels serve as effective functional interface materials that enhance compatibility between human tissues and flexible electronic devices. These hydrogel-based devices exhibit great potential in research areas like smart wearables, health monitoring, and human-machine interfaces. However, traditional hydrogel materials pose challenges in achieving controllable fabrication at the device interface and designing responses to biological and chemical stimuli. These limitations restrain the creation of high-performance hydrogel-based flexible electronic devices for intelligent applications. This article primarily aims to introduce the distinctive material properties of novel DNA hydrogels and their advancements in flexible electronic devices. Initially, we introduced the fabrication techniques for both pure and hybrid DNA hydrogels, alongside strategies for regulating functional interfaces. Subsequently, an in-depth analysis of DNA hydrogels' mechanical properties, stimulus responsiveness, and biocompatibility is provided. Specifically, we explored how these crucial attributes can be harnessed in designing functional devices and biomedical applications. Moreover, we outlined the progress of DNA hydrogel-based flexible electronic devices in sensing, energy storage, and displaying. These advancements showcase their significant potential in human health monitoring and smart wearables. Finally, we discussed the prospective development directions of DNA hydrogels in the domain of flexible bioelectronics.关键词：DNA hydrogel;Stimulus-response;Flexible devices;Sensor
- 644
- |
- 304
- |
- 0
发布时间：2024-06-05
Review
- 摘要：Polymer semiconductor has been widely concerned because of its advantages such as easy to adjust structure and large area solution processing, which can meet the needs of light, thin, soft and transparent flexible electrons. Spiro-fluorenexanthene, as an important functional block of wide-band gap blue light materials, which is often used to construct polymer semiconductors with excellent photoelectric properties and device stability. However, the construction of flexible spiro-fluorenexanthene polymers has rarely been reported. Based on this, this paper reports the efficient synthesis of single/parallel spiro-fluorenexanthene monomers and their blue light-emitting polymers, which include homopolymer PC8SFX-Homo, PDSFX-Homo and copolymers PC8SFX-Co and PDSFX-Co. The parallel spiro-fluorenexanthene polymer (PLQYsol=88.2%, EQEmax=0.52%) is significantly superior to the single spiro-fluorenexanthene system (PLQYsol=11.1% EQEmax=0.17%) in terms of luminous efficiency and flexible device performance. Moreover, the parallel spiro-fluorenexanthene polymer exhibit lower internal stresses. At the same time, introducing the flexible chain segment copolymerization through the main chain flexibility strategy can obtain better flexibility and performance of flexible LED devices. This work provides a new idea for the construction of wide-band gap deep blue light-emitting polymer for the application of flexible electronic and flexible light-emitting display devices.关键词：Spiro-fluorenexanthene;Blue light-emitting polymer;Chain flexibility;Mechanical behavior;Flexible organic light-emitting diodes
- 749
- |
- 171
- |
- 0
发布时间：2024-06-05 - 摘要：Traditional optoelectronic devices suffer from loss of performance due to prolonged use, unavoidable deformation and fracture. To address this issue, it is significant to develop optoelectronic functional materials with strong mechanical tensile properties and self-healing abilities. Herein, we propose a design strategy for self-healing luminescent elastomers based on conjugated polymer backbones. The mechanical tensile properties and self-healing properties of the conjugated polymer are modulated by flexible hydrogen-bonded side chains, while maintaining the intrinsic photophysical characteristics. The synthesized elastomers exhibit excellent mechanical tensile properties (breaking tensile length: 900%), room-temperature self-healing properties (self-healing efficiency: 70%), and high fluorescence quantum efficiency (66%). Importantly, the photophysical properties of the elastomer were essentially fully recovered after undergoing 400% tensile deformation. In addition, we developed multifunctional optoelectronic devices using the prepared elastomers. This study provides a potential design strategy for developing materials for elastic optoelectronic devices.关键词：Flexible electronics;Conjugated polymers;Hydrogen bonds;Self-healing elastomer
- 435
- |
- 221
- |
- 0
发布时间：2024-06-05 - 摘要：The optimization of the active layer morphology is the key to achieving efficient and stable bulk heterojunction organic solar cells (OSCs), and additive engineering is widely used to optimize the film morphology of the active layer in OSCs. A strategy is proposed to optimize the aggregation behavior of donor polymer (PM6) in blended films by using a simple liquid crystal molecule 4-cyano-4'-heptylbiphenyl (7-CB) as an additive. Through wide-angle X-ray scattering, in situ absorption spectroscopy and molecular dynamics simulation, it was found that 7-CB induced the regular arrangement of PM6 through the van der Waals force and CH/π interaction with the alkyl side chain of PM6, which enhanced the interaction between PM6 and PM6, and then enhanced the preaggregation of PM6 in solution, thus improving the crystallites of the active layer film. Benefit from this, charge transfer in the active layer film without any post-treatment is improved, and charge recombination is greatly suppressed. The power conversion efficiency of rigid and flexible binary OSCs prepared by PM6:L8-BO based on 7-CB treatment was increased from 15.41% and 14.90% to 18.01% and 17.26%, respectively.关键词：Organic solar cells;additive;Self-assembly
- 345
- |
- 207
- |
- 0
发布时间：2024-06-05 - 摘要：Elastomer materials with long-lasting and stable room-temperature phosphorescence have great potential in the fields of flexible electronics and photonics. However, developing such materials remains a daunting challenge. Systems of small molecule doped polymers are limited by the tensile properties of the polymer matrix. Currently commonly used poly(methylmethacrylate) (PMMA) and poly(vinyl alcohol) (PVA) have poor tensile properties. However, the increased flexibility cannot provide rigid external conditions for phosphorescence emission. This trade-off parameter adjustment has always hindered its development. Here, we report a highly stretchable and mechanically strong sustainable luminescent room-temperature phosphorescent covalent organic framework elastomer (SPU-D230-UPy COF) material. The material is composed of an alkyl chain soft segment and a limited covalent organic framework containing multiple hydrogen bonding hard segments. This structural design of separated soft and hard segments provides the structural basis for high mechanical properties, high toughness, and phosphorescent emission. The soft segment structure can ensure its high stretchability, and the hard segment structure can provide high mechanical strength while also providing a rigid environment for phosphorescence emission. These prepared elastomers exhibit high mechanical properties and high elasticity, and exhibit bright and sustained luminescence after removal of 365 nm excitation (luminescence time lasts for 3.0 s). Mechanical studies show that the obtained material exhibits a strength of ∼33.5 MPa and excellent toughness of ∼188.26 MJ/m3, with a Young's modulus of ∼76.6 MPa. The material can easily lift heavy objects without breaking. Impressively, these elastomers maintain strong optical properties even under repeated mechanical deformation, an unprecedented property. These outstanding properties make these long-lasting luminescent elastomers ideal for potential applications in wearables, flexible displays, and anti-counterfeiting devices. This separate structural design of soft and hard segments effectively breaks the trade-off between structural flexibility and phosphorescence emission. It can not only improve the mechanical properties, flexibility and stretchability of the material, but also effectively maintain the phosphorescence emission, which will provide a new path for the development of stretchable elastomer phosphorescent emissive materials.关键词：Elastomer;Covalent organic framework;ultralong room temperature phosphorescence;multiple hydrogen bonds
- 466
- |
- 248
- |
- 0
发布时间：2024-06-05 - 摘要：The innovative functional design and flexible integration of microelectronic systems are the driving forces behind the advancement of smart wearable devices in the field of proactive health monitoring. This work employs STM32 control processing chips, temperature and humidity sensors, signal collection and wireless transmission modules, as well as optical components like fiber optics, to design and develop a temperature and humidity data visualization monitoring system. Based on ultra-low modulus silicone nonaqueous gel and 3D spacer fabric as the main materials, a stretchable circuit board with intrinsic and structural flexibility was further fabricated to directly integrate and package this system as a waist-wearable belt-type device for visualizing human microenvironment (data) monitoring. The novel silicone nonaqueous gel composite fabric material used has a Young's modulus and bending stiffness of only 0.113 MPa and 114.680 mN·mm, respectively. Not only did it well retain the inherent soft compliance of fabric substrate, effectively introducing the excellent biocompatibility, hydrophobicity, and electrical insulation of silicone materials, but also achieved further enhancement in mechanical properties such as tensile strength and elongation at break, increased by 48.775% and 22.507%, respectively. The resulting human microenvironment visualization monitoring belt underwent wearable simulation testing on a mannequin, successfully achieving real-time detection and monitoring of temperature and humidity variations in the human microenvironment through color changes in the stretchable fiber optic display board. Moreover, this functional belt, allowing mobile monitoring and data storage thorough smart phones and computers, showcases significant potential in specialized care areas, such as daily care for bedridden elderly.关键词：Flexible electronics;Stretchable circuit board;Human body microenvironment;Physiological data visualization;Health Monitoring and care
- 475
- |
- 222
- |
- 0
发布时间：2024-06-05 - 摘要：The coordination polymerization of polar monomers encounters the significantly challenging and long standing problem in the academic research field, similar to other olefins bearing polar functional groups. However, the key to polymerization is the design of the catalyst. β-Diketiminate ligands have gained increasing popularity since the mid 1990s due to their suitability as spectator ligands.Additionally, β-diketiminate ligands have become some of the most widely used bidentate N-donor ligands in coordination chemistry nowadays. Interest in β-diketiminate complexes was focused mostly on their application in olefin, notably ethylene, polymerization or on investigations of the ligand coordination mode, which varies between in-plane κ2 -coordination and out-of-plane η4/5-coordination. In this work, a series of rare earth metal complexes 1-3 bearing β-diketiminiato ligands featuring aliphatic substituents were designed and synthesized readily. In the presence of cocatalysts [Ph3C][B(C6F5)4] and AliBu3, complexes 2 and 3 were highly active for polymerization of ortho-methoxystyrene (oMOS) to afford syndiotactic polymers (rrrr>99%). These methoxyl functionalized polystyrenes have melting temperatures around 240 ℃ and a Tg of -90 ℃. Complex 2 showed high 1,4 selectivity (88.6%) for isoprene polymerization. Finally, we demenstrate that the stereoselectivity was determined by the coordination patterns of monomer using density functional theory (DFT) calculations clearly.关键词：rare-earth metal catalysts;Syndiotactic;Ortho-methoxystyrene
- 340
- |
- 113
- |
- 0
发布时间：2024-06-05 - 摘要：Deuterated (tritiated) polymers are a type of promissing target materials for inertial confinement fusion. To prepare deuterated polymers with more tritium addition sites, in this work, the deuteration and ring-opening metathesis polymerization of cyclooctadiene was investigated. The mechanism for deuteration reaction of 1,5-cyclooctadiene was studied by analyzing the components of intermediate products during the reaction process. The results of magnetic resonance spectroscopy (1H-NMR, 2H-NMR and 13C-NMR) showed that the by-product of deuterated cyclooctadiene was deuterated cyclooctadiene. The effects of temperature, additives and reaction time on the deuteration rate of products and the yields of by-products were studied, and then the optimized reaction conditions were obtained. Deuterated 1,3-cyclooctadiene with a high deuteration rate up to 96% was prepared. The experiment of ring-opening metathesis polymerization of (deuterated) 1,3-cyclooctadiene was carried out. The existence of a large number of continuous conjugated double bonds led to the crystallization of the polymer, resulting in a poor solubility. In the presence of 5 wt% Pd/BaSO4 and Grubbs second generation catalyst, solid-state catalytic deuteration experiments of poly(1,3-cyclooctadiene) and the copolymers of deuterated 1,3-cyclooctadiene and deuterated cyclooctadiene were carried out. The polymer chain can be added to near saturation with D2, accompanied by obvious hydrogen isotope exchange reaction. A homogeneous solid-phase catalytic hydrogen isotope addition method has been developed. By this method, the well processed deuterated polymer target pellets can be added with tritium directly, and thus the deuterium-tritiated polymer target pellets can be prepared.关键词：Deuteration mechanism;Deuterated polymer;Ring-opening metathesis polymerization;Solid-state catalytic deuteration
- 428
- |
- 319
- |
- 0
发布时间：2024-06-05 - 摘要：In view of the problem that the color nano-latex particles prepared by the copolymerization method have poor color strength, and it is difficult to achieve deep and intensive dyeing of fabrics, this study first screened out the combination of soft and hard monomers with better solubility to polymerizable anthraquinone dyes (AHAQ) by calculating the solubility parameters of commonly used polymeric monomers, and then prepared poly(acrylonitrile/ethyl acrylate) red nano-latex particles (PAEA) by semi-continuous emulsion polymerization. The structure and properties of latex particles were characterized by electronic universal materials testing machine and other instruments, and the effects of factors such as the proportion of hard and soft monomers, the amount of crosslinker divinylbenzene (DVB), the amount of AHAQ, the ratio of oil to water, and the concentration of initiator on the properties of latex particles were explored, and the printing effect of colored latex particles with different solid contents on cotton fabrics was studied. The results showed that the hard monomer acrylonitrile (AN) and the soft monomer ethyl acrylate (EA) had good solubility to the dye, and when the ratio of the two was 1:1.5‒1:2, the obtained latex film had both strength and ductility. The dosage of dye increased from 0.5 wt% to 2.5 wt%, the oil-water ratio increased from 1:8 to 1:4, and the conversion rates of monomer and dye showed a decreasing trend. When the solids content of latex is 30 wt%, the K/S value of the printed fabric is 10.34. Compared with the color latex particles prepared by the previous copolymerization method, the grafting rate of the dye in the latex particles increased significantly, which effectively improved the tinting strength of the color nano latex particles.关键词：Colored latex granules;Nano pigments;Emulsion polymerization;Printing
- 308
- |
- 187
- |
- 0
发布时间：2024-06-05 - 摘要：Due to the depletion of petroleum resources and the development of the emerging bioeconomy, the conversion of biomass into renewable chemicals for the preparation of advanced materials is believed to reduce modern society's dependence on fossil resources. The abundant hydroxyl groups on cellulose make it easy to modify, and it has the advantages of wide source, renewable, biodegradable and excellent bio-co MPatibility. Therefore, the preparation of novel cellulose-based functional materials based on cellulose skeleton has broad application prospects. In 1,8-diazabicyclo[5.4.0]undec-7-ene/dimethyl sulfoxide/CO2 (DBU/DMSO/CO2) solvent system, the transesterification between the hydroxyl groups of cellulose and α-angelicolactone (α-AL) were processed catalyzed by DBU. During this solvent system, the organic base DBU acted as solvent component and catalyst, the cellulose levulinate with high substitution degree (DS) and water solubility could be prepared successfully. In this study, cellulose, α-AL and acid anhydride are used as raw materials to prepare cellulose levulinic acid mixed ester by one-pot method in the same solvent system. The effects of reaction time, temperature and molar ratio of α-AL/anhydride/－OH on monomer conversion rate and DS were studied systematically. The results showed that cellulose levulinic acid mixed ester with DS of 3.0 could be obtained after reaction at 80 ℃ for 3 h. The structure and thermal properties of cellulose levulinic acid mixed ester were studied by magnetic resonance spectroscopy (1H-NMR, 13C-NMR), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). And the relationship between structure and properties of cellulose levulinic acid mixed ester was studied in depth. The results showed that the material had good thermal stability and the glass transition temperature decreased with the extension of side chain alkyl. The mechanical properties of cellulose levulinic acid mixed ester films were investigated by stress-strain experiments. And the results showed that the maximum tensile strength of the CLE-A film reached 32.02 MPa, the elongation at break of CLE-B was 65.83% showing strong and tough characteristics.关键词：Cellulose;Cellulose derivative;Cellulose Levulinate Ester;Mixed Cellulose Levulinate Esters
- 332
- |
- 180
- |
- 0
发布时间：2024-06-05 - 摘要：Poly(lactic acid) (PLA) is one of the most important biodegradable polymers, which has attracted much attention due to its renewable raw materials and excellent biodegradation properties. The quest to develop sustainable and high-performance catalytic technologies as alternatives to the tin catalysts, which are prevalent currently, is a hot topic in this field. Cyclic PLA, contrasting with the extensively produced linear PLA, has garnered significant attention due to its superior crystallinity, thermal stability, and low intrinsic viscosity, and it has been reported that the mixture of cyclic poly(lactic acid) and linear poly(lactic acid) has better hydrolysis resistance and thermal stability. This study reports the design and synthesis of a binuclear guanidine zinc complex, exhibiting exceptional activity (TOF = 7.50×103-3.45×104 h-1) in catalyzing lactide ring-opening polymerization for the efficient production of cyclic poly(lactic acid) under simulated industrial conditions. Gel permeation chromatography (GPC) analysis revealed a narrow, unimodal distribution (1.25-1.49) of the obtained products, with a molecular weight range of 6.2-34.3 kg/mol. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) characterization of low molecular weight products confirmed the predominant presence of cyclic PLA, allowing for the proposal of a plausible ring formation mechanism. Moreover, the experiment demonstrated the binuclear guanidine zinc complex's effective catalytic action on a diverse range of lactone monomers, offering a novel avenue for the development of broad-spectrum catalytic systems within the realm of metal catalysis.关键词：Metal guanidine complex;Lactide;Cyclic poly(lactic acid);Binuclear zinc complex
- 314
- |
- 186
- |
- 0
发布时间：2024-06-05
Research Article
- Postal code：100190
- Tel：010-62588927 Email：gfzxb@iccas.ac.cn
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备05002797号-8
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0