EUROPEAN POLYMER JOURNAL
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2024
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IF 5.8
Guoqing Cui,Chaojie Chen,Yuanlong Li,Li Liu,Guangfeng Wu
The strength and toughness of hydrogel are usually achieved through the synergy of chemical cross-linking and physical cross-linking from multi-component contributions. However, there are few reports on hydrogels that rely on a single component to obtain two cross-linked structures. Herein, we successfully synthesized an amphiphilic macromolecular crosslinker (polyoxyethylene 20 oleyl ether acrylate (O20AC)), and introduced it into a system composed of acrylamide (AAm), sodium chloride (NaCl) and water to prepare the P(AAm-O20AC)/NaCl hydrogel with high strength, outstanding toughness, and excellent good conductivity. Notably, the O20AC possess both crosslinker properties, which not only provide hydrogels with a stable chemical cross-linking network, but also its long hydrophobic chain act as physical crosslinking points to give the hydrogel a new pathway of energy dissipation.Depending on the O20AC crosslinker, the P(AAm-O20AC)/NaCl hydrogels exhibit good strength (tensile stress 714.46 kPa), toughness (elongation at break 3005 %), and fatigue resistance (overlap of hysteresis curves in repeated loading–unloading cycles). Besides, the existence of sodium ions and chloride ions also provides the hydrogel with highly sensitive deformation-dependent conductivity (GF is 5.8 in the 400 %-500 % strain range). Collectively, the strategy of preparing chemical and physical double-crosslinked hydrogels by amphiphilic O20AC will provide a bran-new insights for the development of hydrogel sensing materials.
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
Polymers
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2023
·Vol. 15
·期 19
·3902
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IF 5
Jianyang Shi,Shuang Wang,Haibo Wang,Jun Gu
Hydrogels with flexible and stretchable properties are ideal for applications in wearable sensors. However, traditional hydrogel-based sensors suffer from high brittleness and low electrical sensitivity. In this case, to solve this dilemma, a macromolecular polyurethane crosslinking agent (PCA) was designed and prepared; after that, PCA and two-dimensional (2D) MXene nanosheets were both introduced into a covalently crosslinked network to enhance the comprehensive mechanical and electrochemical properties of the hydrogels. The macromolecular polyurethane crosslinking agent promotes high-tensile strength and highly stretchable capacity by suitable covalent crosslinking. The optimized hydrogel, which exhibited maximum tensile strength and maximum elongation at break, had results of 1.21 MPa and 644%, respectively. Two-dimensional MXene nanosheets provide hydrogel with high electrical conductivity and strain sensitivity, producing a wearable device for the continuous monitoring of human movements and facial microexpressions. This study demonstrated an efficient structure design strategy for building mechanically tough, highly stretchable, and sensitive dual-mode MXenes-based wearable sensors.Keywords:strain sensor;mechanical tough;highly stretchable;sensitive;MXenes;macromolecular crosslinking agent
研究领域:
材料科学
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生物医学工程
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2021
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IF 9.229
Rui Liu,Lei Cui,Haozheng Wang,Qianbing Chen,Ying Guan,Yongjun Zhang
Ideal conductive hydrogels for flexible, wearable strain sensors should be tough, highly resilient, adhesive, and anti-freezing. However, such hydrogels are difficult to design. Herein, a multifunctional macromolecular cross-linker (MC) based on poly(hydroxyethyl-l-glutamine) was designed and used to synthesize the hydrogels. Cross-linking with the MC leads to a reduced inhomogeneity of the gel network. Therefore, the mechanical properties of the gels are significantly improved compared with the ordinary hydrogels cross-linked with the conventional cross-linker N,N-methylenebisacrylamide (BIS). The MC-cross-linked gels also exhibit high resilience. At the same time, replacing BIS with MC significantly improves the adhesive properties of the gel, which is attributed to the introduction of a large amount of adhesive groups with the MC. The gels can stick to various substrates including skin. The good tissue adhesiveness of the gel allows it to stick to skin by itself without using any straps or adhesive tapes when used as a flexible wearable strain sensor. Both large and subtle human movements were successfully monitored using the sensor. The signals are highly stable and reliable, thanks to the high resilience of the gel. The introduction of the polar groups also improved dramatically the anti-freezing properties of the gels. Even at −20 °C, the gels still remained highly flexible and stretchable, therefore allowing the gel-based sensor to work at sub-zero temperatures. The excellent toughness, resilience, tissue-adhesiveness, and anti-freezing properties of the gel make it a good choice for a flexible wearable sensor.
研究领域:
材料科学
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生物医学工程
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纳米技术
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DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
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2013
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IF 4.675
Wangting Lu,Zhi-Gang Shao,Geng Zhang,Yun Zhao,Baolian Yi
A new material based on crosslinked poly(vinylbenzyl chloride) (PVBC) with a macromolecular crosslinker is synthesized and employed as the membrane for anion exchange membrane fuel cells (AEMFCs). PVBC is used as the hydroxide conducting polymers , while poly(vinyl acetal) (PVAc) containing dimethylamino groups plays the role as macromolecular crosslinker and the supporting matrix simultaneously. Fourier transform infrared (FT-IR) absorption spectra and X-ray photoelectron (XPS) spectra prove successful crosslinking between PVBC and PVAc. The crosslinked membrane shows hydroxide conductivity larger than 0.01 S cm −1 at room temperature , and the swelling by water at elevated temperature is suppressed. The H 2 /O 2 AEMFC using the crosslinked membrane shows a peak power density ( P max ) of 124.7 mW cm −2 at 40 °C, and the decrease of the open circuit voltage (OCV) of the fuel cell is negligible under continuous OCV conditions for 120 h. All the results indicate that the crosslinking with a macromolecular crosslinker may be a promising strategy to fabricate anion exchange membrane for the application in the AEMFCs.
研究领域:
材料科学
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电化学
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能源工程
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DOI
高影响因子
BIOMACROMOLECULES
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2021
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IF 6.988
Cailing Zhao,Zejia Wu,Hanyu Chu,Tao Wang,Shuai Qiu,Jing Zhou,Qingtang Zhu,Xiaolin Liu,Daping Quan,Ying Bai
Extrusion-based bioprinting is an emerging and most frequently used technique for the fabrication of cell-laden constructs. A suitable hydrogel-based bioink for cell encapsulation and protection is critical for printability, structural stability, and post-printing cell viability. The thiol–ene chemistry-based gelatin-norbornene (GelNB) hydrogels have drawn much attention as a promising substitution of gelatin methacryloyl (GelMA), owing to the fast and controllable step-growth polymerization mechanism, as well as a significant reduction in reactive oxygen species (ROS) accumulation. Herein, thiolated heparin (HepSH) was synthesized and used as a macromolecular crosslinker for GelNB-based bioprinting, so that GelNB gelation became less sensitive to the thiol/ene ratio. The mechanical stability and moduli of GelNB/HepSH hydrogels were easily manipulated by the concentration and/or degree of thiol substitution. The GelNB/HepSH hydrogel allowed little intracellular ROS for encapsulated cells but provided vascular endothelial growth factor binding affinity for potential facilitation of neovascularization. Finally, the GelNB/HepSH bioink enabled a convenient printing process for both complex-structured bioscaffolds and cell-laden constructs, and resulted in good printability and high post-crosslinking cell viability. The crosslinker HepSH may serve as a multifunctional macromolecule that enables GelNB-based bioprinting in broad applications in regenerative medicine.
研究领域:
生物打印
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再生医学
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材料科学
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组织工程
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）