APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Sishi Xu,Wencheng Liang,Guanzhe Xu,Chengjie Huang,Junyong Zhang,Meidong Lang
Optimal modification and gelation strategies of polysaccharide hydrogels have been developed for biomedical applications. Herein, a kind of fast crosslinking alginate hydrogel with superior gel properties was prepared for the first time combining dual crosslinking mechanisms. Firstly, sodium alginate (SA) was modified by vinyl ether side chains through one-step amidation reaction with aminopropyl vinyl ether (APVE) catalyzed by EDC/NHS. Just within 10 s, the grafting product of SA-VE was demonstrated to form hydrogen bonded hydrogel SA-VE/H 2 O spontaneously. Based on this mechanism, a dual crosslinking alginate hydrogel SA-VE/DTT was fabricated through introducing thiol-ene click chemistry reaction with dithiothreitol (DTT) under UV exposure. According to rheological results, the photo-crosslinking process was completed within 5–9 min. Combining hydrogen bonding and thiol-ene click chemistry, the dual crosslinking mechanism was proved to bring the hydrogel system not only fast gelation but also superior storage modulus up to 13373 Pa and excellent stability of over 1 month. All the hydrogels exhibited non-cytotoxicity towards NIH-3T3 fibroblasts. Furthermore, the 26 s rapid hemostasis behavior of SA-VE exhibited in rat tail hemostasis experiment reveals its potential application in wound dressing materials.
研究领域:
生物材料学
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组织工程
·
再生医学
✓ 已验证
DOI
高影响因子
CARBON
·
2025
·
IF 11.6
Yuting Liu,Heping Niu,Zhihong Wang,Jialin Liang,Liang Ren,Jisheng Zhou
Hard carbons (HCs) derived from pitch show promise as low-cost anodes for sodium-ion batteries (SIBs) due to their high carbon yield. However, pitch's complex polyaromatic structure makes its modification and HC microstructure control difficult. This study selects bicyclic naphthalene (Nap), tricyclic phenanthrene (Phe) and tetracyclic pyrene (Pyr) as model precursors to investigate how the aromatic ring number impacts HCs' cross-linking mechanisms, microstructure, and electrochemical performance. HCs based on Nap, Phe and Pyr are prepared via combined molecular and oxidative cross-linking. After molecular cross-linking, polycyclic aromatic resin's layer size and aromaticity grow with precursor ring number, R-Pyr having the largest aromatic layers and strongest π-π interactions. During oxidative cross-linking, these layers enhance –C(O)O group retention and 3D stacking, leading to closed pores with smaller size, larger volume, and thicker graphite microcrystals. Consequently, Pyr-based HCs (Pyr-HC) exhibit superior electrochemical performance, with a reversible capacity of 328.20 mAh g −1 at 0.1 A g −1 . In full-cell tests, the Pyr-HC || NVP reaches 184.8 mAh g −1 at 1 A g −1 and an energy density of 147.2 Wh kg −1 , retaining 74.78 % of its capacity after 200 cycles. This work highlights the importance of precursor structure for HC optimization and screening pitch precursors.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2024
·Vol. 16
·期 22
·3123
·
IF 4.7
Na Meng,Xin Sun,Jinxin Liu,Jialing Mi,Rong Rong
In recent years, graphene oxide (GO)-based two-dimensional (2D) laminar membranes have attracted considerable attention because of their unique well-defined nanochannels and deliver a wide range of molecular separation properties and fundamentals. However, the practical application of 2D GO layered membranes suffers from instability in aqueous solutions as the interlayerd-spacing of GO membranes is prone to expansion caused by the hydration effect. In this study, the effects of the ethylenediamine (EDA) addition amount on the structure, crosslinking mechanism and separation performance of GO membranes were investigated systematically, and membrane performance was evaluated using water permeability and dye/salt rejection tests. The experimental results show that the amine groups of EDA chemically bond with the hydroxyl functional group (O=C–OH) of GO after intercalation, as evident from Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). By further controlling the amount of the intercalated EDA, the as-prepared GO composite membranes show nanoscale-tunedd-spacing promising for downstream applications. In the demonstrated dye/salt nanofiltration scenario, the EDA intercalated and crosslinked GO membrane has enhanced permeability by over five times and a better dye rejection rate of over 96% compared with pure GO membranes. These findings highlight a facile strategy for controlling nanochannels by tuning the amounts of reactive intercalants.
研究领域:
材料科学
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化学工程
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
IRANIAN POLYMER JOURNAL
·
2019
·Vol. 28
·期 2
·157-166
·
IF 1.707
Zhang Guangyan,Zhou Jun,Wang Peng
A novel cross-linkable polyaspartamide derivative-containing cinnamoyl pendant groups, P(HPA-Az)-CA, was designed and synthesized in this study. Chemical structures of the obtained polymers were confirmed by FTIR, UV, and 1 H NMR techniques. The transmittance measurement results showed that the prepared polymer P(HPA-Az)-CA displayed temperature and pH dual stimuli-responsive behaviors. The cloud point of P(HPA-Az)-CA could be tuned just by adjusting the introduced percentage of hydrophobic moieties or the pH of polymer aqueous solution. The effect of pH on the cloud point of P(HPA-Az)-CA was investigated by zeta potential, and the results showed that it may be related to the weakened electrostatic repulsion caused by decreased zeta potential with pH decreasing. Diamines (ethylenediamine or cystamine) were adopted to prepare cross-linked micelles using the mixture of P(HPA-Az)-CA aqueous solution and diamines just by one-step heating method. The cross-linked micelles were stable, even when the environmental temperature was below the cloud point of P(HPA-Az)-CA. The cross-linking mechanism between the diamines and α,β-unsaturated carbonyl moieties of P(HPA-Az)-CA was confirmed by 1 H NMR. In addition, the micelles cross-linked with cystamine could be disrupted in the presence of 10 mM glutathione. According to the results, the obtained polyaspartamide derivative P(HPA-Az)-CA may be a potential for facilitating drug loading.
研究领域:
高分子化学
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药物传递系统
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Mingwei Zhao,Yang Li,Zhongliang Xu,Kai Wang,Mingwei Gao,Wenjiao Lv,Caili Dai
In petroleum exploitation, fracturing is a very important technique for the reservoir with low porosity and permeability. The fracturing fluid is the key to fracturing operation. Due to the limitation of lithology complexity, it is difficult for conventional acid-based fracturing fluids to meet technical requirements during the production of carbonate oil and gas resources. In this work, a novel acid gel fracturing fluid was designed. The system has high viscosity which is convenient to carry proppant. Meanwhile, the fluid has good basic properties to meet on-site operation requirements. Since the properties of fracturing fluid depend not only on the molecular structure of thickener, but also on the crosslinked structure formed by polymer and crosslinker. The dynamic cross-linking mechanism of this acid gel fracturing fluid system was focused on. The differences in fluid properties between polymer based fluid and fracturing fluid were investigated by conducting viscoelastic tests. A rheological dynamic model based on the change of viscosity with reaction time was established. The effect of shear rate on cross-linking viscosity and reaction rate was studied. Moreover, the microstructure changes of the system before and after the gelation reaction were revealed through the scanning electron microscopy (SEM) experiment. Based on these experimental results, the cross-linking mechanism of this novel acid gel fracturing fluid can be concluded, which benefits the application in oilfield.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
Foods
·
2022
·Vol. 11
·期 22
·3722
·
IF 5.561
Hongbin Wang,Yuanfu Zhang,Zhaoting Yuan,Xiaotong Zou,Yuan Ji,Jiayi Hou,Jinfang Zhang,Fuping Lu,Yihan Liu
Until now,Streptoverticillium mobaraensetransglutaminase (TG) is the only commercialized TG, but limited information is known about its selection tendency on crosslinking sites at the protein level, restricting its application in the food industry. Here, four recombinantBacillusTGs were stable in a broad range of pH (5.0–9.0) and temperatures (<50 °C), exhibiting their maximum activity at 50–60 °C and pH 6.0–7.0. Among them, TG ofB. cereus(BCETG) demonstrated the maximal specific activity of 177 U/mg. A structural analysis indicated that the Ala147-Ala156 region in the substrate tunnel of BCETG played a vital role in catalytic activity. Furthermore, bovine serum albumin, as well as nearly all protein ingredients in soy protein isolate and whey protein, could be cross-linked by BCETG, and the internal crosslinking paths of three protein substrates were elucidated. This study demonstratedBacillusTGs are a candidate for protein crosslinking and provided their crosslinking mechanism at the protein level for applications in food processing.Keywords:transglutaminase;enzymatic characterization;structural analysis;crosslinking properties;protein substrate crosslinking mechanism
研究领域:
食品科学
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生物化学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2024
·Vol. 59
·期 45
·20929-20943
·
IF 3.5
Ye Cai,Li Xiaohong,Chen Jianjun,Hafsa
Crosslinking is a crucial step to keep fibrous morphology and improve ceramic yield in the fabrication process of SiC fibers. Comparing with the oxygen crosslinking, thermal crosslinking can reduce the introduction of oxygen within fibers. In this study, a novel method for preparing the SiC fibers was proposed by combining dry spinning and thermal crosslinking. The spinning solution was prepared by blending a low-molecular-weight (~ 1000 Da) polycarbosilane (PCS) with polyisobutene (PIB) as spinning additive, acrylic acid (AA) as crosslinking agent, and 2,2'-Azobis (2,4-dimethyl) valeronitrile (ABVN) as initiator. The crosslinking mechanism, morphology, composition and microstructure, and mechanical properties of fibers were investigated. The results showed that the morphology of AA-containing PCS fibers was well preserved at 300 ℃ with a low heating rate (0.5 ℃/min), while PCS fibers without AA exhibited the melting or deformation. The crosslinking reaction between C = C groups in AA-containing PCS and Si–H bonds in PCS was triggered by ABVN. Furthermore, AA-containing PCS green fibers experienced pyrolysis at 1100 ℃ and then were annealed at 1500 ℃ (denoted as SiC-1500). SiC-1500 fibers, with an average diameter of 10.47 ± 0.50 μm and average tensile strength of 1.35 ± 0.65 GPa, have a smooth surface and relative dense structure. But SiC-1500 fibers were still an amorphous structure due to the suppression of graphite phase for the growth of β-SiC grains. This work not only breaks through the limitations that only uses high-molecular-weight PCS for dry spinning, but also successfully combines dry spinning and thermal crosslinking technology to obtain SiC fibers. Graphical abstract
研究领域:
材料科学
·
陶瓷学
·
纤维科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2022
·
IF 6.633
Siyu Han,Zhuang Hu,Wanhong Zhang,Jianshe Hu,Liqun Yang
Aliphatic polycarbonates gels have received unprecedented attention due to their environmentally friendly and sustainable properties. However, traditional aliphatic polycarbonates gels lacking functionalization properties are not able to meet the requirements of future innovations. Based on this situation, in this study, novel functionalized aliphatic polycarbonate gels PEG 2000 - b -P(TMC-co-MCC) n are developed. The formation of hydrogen bonds network endows the gel with good comprehensive performances. Accordingly, the gel possesses a tensile strength and stretchability up to 2.62 MPa and 397.7%, presents a shape recovery rate of 97.7% in 9 s at 30 °C and also can repair crack at room temperature for 4.5 h without any external stimulation. Furthermore, these performances can be regulated by the ratio of the flexible segment, and the specific relationships between them are also presented. Notably, the cross-linking mechanism of the gels PEG 2000 - b -P(TMC-co-MCC) n is also proposed. Significantly, the transition states, energy barriers and reaction enthalpies of each step in the formation of oligomers by ring-opening polymerization of small molecules are calculated by density functional theory to deepen the understanding of the reaction mechanism. This aliphatic polycarbonate gel with excellent shape memory and self-healing properties provides prospects for developing the biomaterials such as surgical sutures and stents, as well as flexible electronics.
研究领域:
材料科学
·
聚合物化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）