RSC Advances
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2018
·Vol. 8
·期 15
·8011-8020
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IF 2.936
Xiaoqing Wang,Chengyuan Li,Zhenyu Shi,Mingjia Zhi,Zhanglian Hong
In our previous work, a citric acid assisted sol–gel method was developed for preparing monolithic metal oxide aerogels. Such method adopted citric acid as the gelator, which replaced the well-studied proton scavenger propylene oxide. In this work, we have further extended this “organic acid assisted” sol–gel method and investigated the gelation mechanism. Four different organic acids (butanedioic acid, L-malic acid, L-aspartic acid and mercaptosuccinic acid) with an identical main chain but different side groups were used as the gelators for preparing monolithic zirconia aerogels. It was found that complex interactions including covalent bond and coordination bond interactions between organic acids and zirconium ions were vital to give a rigid gel network. After supercritical drying, crystalline zirconia aerogels can be obtained with high surface areas over 330 m2 g−1 and large pore volumes over 3.574 cm3 g−1.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
ACS Nano
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2022
·
IF 18.027
Qingqing Cheng,Zhizhi Sheng,Yongfeng Wang,Jing Lyu,Xuetong Zhang
Aerogels represent a kind of nanoporous solid with immense importance for a plethora of diverse applications. However, on-demand conformal shaping capacity remains extremely challenging due to the strength unfavorable during aerogel processing. Herein, a universal microgel-directed suspended printing (MSP) strategy is developed for fabricating various mesoporous aerogels with spatially stereoscopic structures on-demand. As a proof-of-concept demonstration, through the rational design of the used microgel matrix and favorable printing of the Kevlar nanofiber inks, the Kevlar aerogels with arbitrary spatial structure have been fabricated, demonstrating excellent printability and programmability under a high-speed printing mode (up to 167 mm s–1). Furthermore, the custom-tailored Kevlar aerogel insulator possessing superior thermal insulation attribute has ensured normal discharge capacity of the drone even under a harsh environment (−30 °C). Finally, various types of spatial 3D aerogel architectures, including organic (cellulose, alginate, chitosan), inorganic (graphene, MXene, silica), and inorganic–organic (graphene/cellulose, MXene/alginate, silica/chitosan) hybrid aerogels, have been successfully fabricated, suggesting the universality of the MSP strategy. The strategy reported here proposes an alternative for the development of various customized aerogels and stimulates the inspiration to truly arbitrary architectures for wider applications.
研究领域:
材料科学
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纳米技术
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增材制造
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热工程
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2024
·
IF 6.1
Xin Guan,Mengliang Bi,Shengyu Sun,Yongqi Yang,Jian Sun,Zhaohui Jin,Hailun Ren,Zijian Gao
A hydrogel is an ideal matrix material for flexible electronic devices, electronic skin and health detection devices due to its outstanding flexibility and stretchability. However, hydrogel-based flexible electronic devices swell once they are placed in a high humidity or underwater environment. The swelling behavior could damage the internal structure of hydrogels, ultimately leading to the reduction or complete loss of mechanical properties, electrical conductivity and sensing function. In order to resolve the above problems, a double network ionogel with remarkable anti-swelling behavior, stretchability and conductive properties was prepared. The ionogel consisted of gelatin (G) and copolymerization of acrylic acid (AA), 2-hydroxyethyl methacrylate (HEMA), butyl acrylate (BA), dimethylaminoethyl methacrylate maleate (D) and N,N′-methylene-bis-acrylamide (MBAA). Due to the dense crosslinking network and hydrophobic interaction, the ionogel exhibited remarkable anti-swelling properties (7.64% of the 30-day equilibrium swelling ratio in deionized water). D and MBAA were simultaneously introduced into the ionogel system as cross-linking agents to provide a large number of cross-linking points, improving the cross-linking density of the ionogel. Importantly, the introduction of D avoided ionic leakage by free radical copolymerization. Furthermore, the ionogel maintained stable mechanical properties and conductivity after being submerged in deionized water owing to remarkable anti-swelling performance. The mechanical properties of the ionogel retained 89.75% of the initial mechanical properties after a 5-day immersion in deionized water. Therefore, this ionogel could be employed as an underwater flexible wearable sensor for high humidity or underwater motion monitoring.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Kailu Wang,Shangwei Wang,Xiaoyu Wang,Xiaoqing Wang,Lijun Zheng,Jie Wen,Huan Yang,Hui Zhang
To address the issue of traditional gels being prone to dewatering and failure under reservoir conditions, this study prepared a new type of magnetic smart gel by 'chelating' PEI@Fe 3 O 4 @PEI nanosheets within the PAM-PEI gel network. The nanosheets possess a 'sandwich' structure formed through self-assembly driven by electrostatic forces, with a density of 2.719 g/cm 3 . Under 90 °C and with a NaCl concentration of 25 g/L, the control PAM-PEI gel had a syneresis rate of 5.96 % and a gel strength of 17.13 Pa·s. In comparison, the magnetic smart gel had a syneresis rate of 0 % and a gel strength of 27.38 Pa·s, indicating that the magnetic smart gel outperformed the control significantly. Possible mechanisms by which nanosheets enhance the performance of magnetic smart gels include: enhancing the hydrophilicity of the molecular chains, inhibiting the breakage of C-N bonds in the polymer chains, increasing the gel's resistance to water loss at high temperatures, and hindering the pyrolysis of PAM groups. Lastly, the work explores the advantages of magnetic smart gels in effective plugging, rapid unplugging post-lifespan, and simplified produced water treatment through its controlled operational capabilities. To implement these applications effectively, field devices need to be equipped with innovative designs.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
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2024
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IF 4.2
Yanyu Yang,Ying Xiao,Xiang Wu,Junjie Deng,Rufang Wei,Ashuang Liu,Haiyang Chai,Rong Wang
Smart hydrogels responsive to external stimuli are promising for various applications such as soft robotics and smart devices. High mechanical strength and fast response rate are particularly important for the construction of hydrogel actuators. Herein, tough hydrogels with rapid response rates are synthesized using vinyl-functionalized poly( N -isopropylacrylamide) (PNIPAM) microgels as macro-crosslinkers and N -isopropylacrylamide as monomers. The compression strength of the obtained PNIPAM hydrogels is up to 7.13 MPa. The response rate of the microgel-crosslinked hydrogels is significantly enhanced compared with conventional chemically crosslinked PNIPAM hydrogels. The mechanical strength and response rate of hydrogels can be adjusted by varying the proportion of monomers and crosslinkers. The lower critical solution temperature (LCST) of the PNIPAM hydrogels could be tuned by copolymerizing with ionic monomer sodium methacrylate. Thermo-responsive bilayer hydrogels are fabricated using PINPAM hydrogels with different LCSTs via a layer-by-layer method. The thermo-responsive fast swelling and shrinking properties of the two layers endow the bilayer hydrogel with anisotropic structures and asymmetric response characteristics, allowing the hydrogel to respond rapidly. The bilayer hydrogels are fabricated into clamps to grab small objects and flowers that mimicked the closure of petals, and it shows great application prospects in the field of actuators.
研究领域:
材料科学
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软体机器人
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智能设备
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产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2021
·Vol. 26
·期 7
·1960
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IF 4.412
Xingzhong Guo,Zixiao Li,Wei Lei,Ronghua Ding,Yun Zhang,Hui Yang
Microwave heating technology is known as an alternative to traditional gas and electric heating sources. In this work, mesoporous methylsilsesquioxane (MSQ) aerogels were prepared via a sol–gel process accompanied by microwave heating technology, and microwave heating was used in the gelation of sol and the drying of wet gels, respectively. The effects of hexadecyltrimethylammonium chloride (CTAC) as a surfactant and template, hydrochloric acid (HCl) as a catalyst, ethanol as a solvent, sodium hydroxide (NaOH) as a gelation agent, and microwave power on the pore structure of as-prepared MSQ aerogels were investigated in detail. Microwave heating at low power results in the acceleration of sol–gel transition and achieves the gelation within a few minutes. Appropriate amounts of chemical reagents and microwave heating at high power allow the preparation of mesoporous MSQ aerogels with a BET-specific surface area of 681.6 m2·g−1and a mesopore size of 19 nm, and the resultant MSQ aerogel still has a BET specific surface area as high as 134 m2·g−1after heat treatment at 600 °C for 2 h, showing high thermal stability. The MSQ aerogels/fibre composite possesses a low thermal conductivity of 0.039 W/(m·k)−1, displaying good thermal insulation. Microwave heating technology is a promising heating method for the preparation of other aerogels.Keywords:MSQ aerogels;microwave drying;sol–gel
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 46
·12026-12031
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IF 4.696
Si Chen,Xiao Luo,Huiwen He,Xiaoqian Tong,Bozhen Wu,Meng Ma,Xu Wang
A unique stretchable liquid crystal light scattering display is reported in this paper with clear images shown at a maximum strain of 145% of the original length, based on super strong liquid crystalline physical gels with special loofah-like 3D gel networks.
研究领域:
材料科学
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光学
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高分子化学
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2014
·Vol. 16
·期 30
·6901-6906
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IF 3.858
Liao Chen,Tao Ye,Yujing Liu,Wei Liu,Gang Wu,Hongzheng Chen,Hanying Li
Gel-grown single-crystal composites where gel networks are incorporated inside single-crystals have been reported in an increasing number of studies, with the composite structure similar to that of the biogenic biomacromolecule-incorporated single-crystals. However, the mechanisms of the gel incorporation are still not clear. In this work, we examined the growth of four types of crystals (NaF, NaCl, KBr and potassium dihydrogen phosphate (KDP)) in both silica gels and agarose gels to assess the effects of the crystal–gel interaction and the gel structure on the gel incorporation. In all of the eight crystal–gel pairs, single-crystals were obtained by single-crystal X-ray diffraction analysis. Dissolution of the crystals revealed that all of the four types of crystals grown from the agarose gels incorporated the gel networks during crystallization. In contrast, NaF and KDP crystals incorporated the silica gel networks but NaCl and KBr did not when grown from silica gels. The discrepancies among the eight crystal–gel pairs suggest that crystal–gel interaction (hydrogen bond) and fibre-like gel structure with large gel strength favour the gel incorporation. This work may facilitate understanding of the formation mechanisms of single-crystal composites.
研究领域:
材料科学
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晶体学
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DOI
高影响因子
LANGMUIR
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2022
·
IF 4.331
Jirui Wei,Min Lin,Xiaohui Fu,Jing Sun
Nature-made hydrogels typically combine a wide range of multiscale fibers into biological composite networks, which offer an adaptive property. Inspired by nature, we report a facile approach to construct hybrid hydrogels from a range of natural or commercially available synthetic nongelling polymers (e.g., poly(ethylene glycol), poly(acrylic acid), carboxylated cellulose nanocrystal, and sodium alginate) at a concentration as low as 0.53 wt % using a nonionic fibrous peptide hydrogelator. Through simply mixing the peptide hydrogelator with a polymer aqueous solution, stable hybrid hydrogels can be formed with the concentration of hydrogelator at ∼0.05 wt %. The gel strength of the resulting hydrogels can be effectively modulated by the concentration, molecular weight, and terminal group of the polymer. We further demonstrate that the molecular interactions between the peptide hydrogelator and the polymer are very crucial for the formation of hybrid hydrogel, which synergically induce the gelation at considerably low concentrations. A peptide hydrogelator can be easily obtained by aminolysis of alkyl-oilgo(γ-benzyl-l-glutamate) samples. Live/Dead assays indicate low cytotoxicity of the hybrid hydrogel toward HeLa cells. Combining the low-cost, scalable synthesis, and biocompatibility, the prepared peptide hydrogelator presents a potential candidate to expand the scope of polymer hydrogels for biomedical applications and also shows considerable commercial significance.
研究领域:
材料科学
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生物医学工程
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化学工程
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Meijin Zhao,Wenshuai Zhang,Peipei Sun,Lei Shi,Yuhua Liu,Xingshuang Zhang,Lei Zhang,Wenjia Han,Pu Chen
Flexible hydrogel-based sensors have attracted considerable interest for their potential applications in human motion detection, physiological monitoring, and electronic skin. However, the durability of hydrogel sensors is seriously hindered due to inevitable water evaporation and the lack of reusability. Herein, inspired by the skin’s delamination structures that perform sensing and barrier functions, packaged hydrogel strain sensors (PHSSs) were fabricated by employing injectable conductive hydrogel wires as strain sensing elements and another photopolymerizable hydrogel film as an external packaging layer. Thanks to the packaging strategy, multiple properties of the high sensitivity (GF = 1.63 at a strain range of 0–100%), linear sensing property (R2 > 0.99), good transparency (∼85% transmittance), and conformal adhesion (0.24–1.53 kPa) were integrated into one PHSS, which was further demonstrated to possess the capability of detecting human motions and electrophysiological signals precisely. More importantly, the enhanced lifespan (2.5 times) was achieved as a result of water evaporation inhibition by packaging, while the swelling property of the external hydrogel film endowed the PHSS with good reusability (reused for three cycles). This study provides a new strategy for fabricating sustainable hydrogel-based electronics.
研究领域:
生物医学工程
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柔性电子学
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
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2022
·
IF 3.466
Jing Wang,Lin Ren,Zhan Yu,Rui Teng,Changwei Pan,Ling Yuan,Irving R. Epstein,Qingyu Gao
The Belousov–Zhabotinsky (BZ) self-oscillating gel is a unique actuator suited for studying the behavior of intelligent soft robots. However, the traditional BZ self-oscillating polyacrylamide (PAAm) gel is easily broken and is slow to response to stimuli, which limits its practical application. Therefore, the preparation of BZ gels with sensitive responses to external stimuli and desirable, robust mechanical properties remains a challenge. In this work, PAAm-activated nanogels with unpolymerized double bonds are used as nanocrosslinkers to synthesize a nanogel crosslinking-based BZ (NCBZ) self-oscillating PAAm gel, whose mechanical properties, for example, antipuncture, cutting, and tensile properties, are superior to those of traditional PAAm BZ-self-oscillating gels. The oscillatory period of the traditional gel is much longer than that of the corresponding homogeneous BZ system, resulting from the slow response of the gel to changes in redox potential, whereas large, interconnected pores inside the NCBZ gel provide efficient channels for rapid species transport, supporting fast response of the gel, which results in almost the same period of chemomechanical oscillations as the homogeneous system under the same conditions. Scanning electron microscopy results show that the NCBZ gel is more stable than the traditional BZ PAAm gel after 7 h of oscillation. Our results make it possible to prepare robust gel motors and provide promising application prospects for smart soft robots, actuators, sensors, tissue engineering, and other applications.
研究领域:
材料科学
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智能软机器人
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化学工程
✓ 已验证
DOI
高影响因子
Pharmaceutics
·
2023
·Vol. 15
·期 8
·2161
·
IF 5.4
Fen Zheng,Wei Du,Minggang Yang,Kaige Liu,Shanming Zhang,Long Xu,Yong Wen
Bacterial infections, especially antibiotic-resistant bacterial infections, pose a significant threat to human health. Supramolecular gel with innate antibacterial properties is an advanced material for the treatment of bacterial infections, which have attracted great attention. Herein, a reactive oxygen species (ROS)-responsive innate antibacterial supramolecular gel is developed by a bottom-up approach based on phenylalanine and hydrazide with innate antibacterial properties. The structure of gelators and intermediate products was characterized by proton nuclear magnetic resonance (1H NMR) and a high-resolution mass spectrum (HRMS). The results of1H NMR and the Fourier transform infrared spectrum (FT–IR) experiment disclosed that hydrogen bonding and the π–π stacking force are the important self-assembly driving forces of gelators. The microstructure and mechanical properties of gel were studied by Scanning electron microscope (SEM) and Rheometer, respectively. An in vitro degradation experiment proved that the gelator has ROS-responsive degradation properties. The in vitro drug release experiment further manifested that antibiotic-loaded gel has ROS-responsive drug-release performances. An in vitro cytotoxicity experiment showed that the supramolecular gel has good biocompatibility and could promote cell proliferation. The in vitro antibacterial experiment proved that the supramolecular gel has excellent inherent antibacterial properties, and the antibacterial rate againstStaphylococcus aureus(S. aureus) andEscherichia coli(E. coli) was 98.6% and 99.1%, respectively. The ROS-responsive supramolecular gel as a novel antibacterial agent has great application prospects in treating antibiotic-resistant bacterial-infected wounds and preventing the development of bacterial resistance.Keywords:antibacterial gel;supramolecular gel;ROS-responsive;low molecular weight gelator;biocompatibility
研究领域:
材料科学
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医学
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生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）