Journal of Energy Chemistry
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2016
·
IF 2.322
Lu Li,Dezhang Ren,Jun Fu,Yunjie Liu,Fangming Jin,Zhibao Huo
An efficient process for the conversion of dimethyl oxalateinto ethylene glycol with high selectivity and high yield over Cu 2 O was investigated. In situ formed Cu as a true catalytically active species showed a good catalytic performance for DMO conversion to produce EG in 95% yield.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
·
IF 8.025
Lei Luo,Qing Zhou,Yingkui Hu,Qiang Ding,Zongbao Zhou,Chuang Wang,Xiaoying Wang,Hang Li,Shunqing Tang
The immunostimulatory activity of polysaccharides can improve human immunity, but their activity is low and prompting the activity is a great challenge. Curdlan, is a linear beta-1,3-glucan and has the potential to induce immune responses. However, owing to its tight triple helix structure and insolubility in water, its immunostimulatory activity is weakened. The keyway to promote its immunostimulatory activity is to relax its tight triple helix structure. In this work, methoxypolyethylene glycol (mPEG) was grafted onto curdlan (curdlan- g -mPEG) to unwind its triple helix structure. With its grafting mPEG, the water solubility of curdlan was enhanced. Moreover, with curdlan- g -mPEG treatment, macrophages secreted more tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 and exhibited favorable phagocytosis of bacteria ( Staphylococcus aureus and Pseudomonas aeruginosa ). These results reveal that curdlan- g -mPEG as an immunostimulant has potential applications in immunology and antibiotics.
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PubMed
高影响因子
Acta Biomaterialia
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2016
·
IF 6.008
Jianbing Wu,Zhaozhu Zheng,Gang Li,David L. Kaplan,Xiaoqin Wang
A one step, rapid method to prepare silk microspheres was developed, with particle size controlled by the addition of polyethylene glycol (PEG). PEG molecular weight (4.0 K–20.0 KDa) and concentration (20–50 wt%), as well as silk concentration (5–20 wt%), were key factors that determined particle sizes varying in a range of 1–100 μm. Addition of methanol to the PEG-silk combinations increased the content of crystalline β-sheet in the silk microspheres. To track the distribution and degradation of silk microspheres in vivo , 3-mercaptopropionic acid (MPA)-coated CdTe quantum dots (QDs) were physically entrapped in the silk microspheres. QDs tightly bound to the β-sheet domains of silk via hydrophobic interactions, with over 96% of the loaded QDs remaining in the silk microspheres after exhaustive extraction. The fluorescence of QDs-incorporated silk microspheres less stable in cell culture medium than in phosphate buffer solution (PBS) and water. After subcutaneous injection in mice, microspheres prepared from 20% silk (approx. 30 μm diameter particles) still fluoresced at 24 h, while those prepared from 8% silk (approx. 4 μm diameter particles) and free QDs were not detectable, reflecting the QDs quenching and particle size effect on microsphere clearance in vivo . The larger microspheres were more resistant to cell internalization and degradation. Since PEG is an FDA-approved polymer, and silk is FDA approved for some medical devices , the methods developed in the present study will be useful in a variety of biomedical applications where simple, rapid and scalable preparation of silk microspheres is required. Statement of Significance The work is of significance to the biomaterial and controlled release society because it provides a new option for fabricating silk microspheres in one simple step of mixing silk and polyethylene glycol (PEG), with the size and properties of microspheres controllable by PEG molecular weight as well as PEG and silk concentrations. Although fabrication of silk microspheres have been reported previously using spray-drying, liposome-templating, polyvinyl alcohol (PVA) emulsification , etc., applications were hindered due to harsh conditions (temperature, solvents, etc.) and complicated procedures used as well as low yield and less controllable particle size (usually <10 μm). Since PEG is an FDA-approved polymer, and silk is FDA approved for some medical devices, the methods developed in the present study will be useful in a variety of biomedical applications where simple, rapid and scalable preparation of silk microspheres is required.
研究领域:
生物材料学
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控释系统
·
医学工程
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2016
·Vol. 133
·期 36
·
IF 1.866
Jiangquan Liu,Xiaoguang Ying,Hongxun Wang,Xiao Li,Weiying Zhang
Polyethylene glycol grafted calcium alginate hydrogel microspheres are synthesized by ring-opening and addition reaction of epoxy chloropropane. FTIR, 13 C NMR, optical microscope, SEM, TG, and DSC are used for characterization. Swelling behaviors are studied and it is found that polyethylene glycol grafted calcium alginate microspheres are improved in anti-swelling properties. Protein-imprinted polyethylene glycol grafted calcium alginate hydrogel microspheres exhibit enhanced specific rebinding quantity (11.16 mg/g) and selective recognition properties (4.71 against BHb), towards target molecule in the presence of competing protein, compared with that of the unmodified samples (4.96 mg/g and 1.75, respectively). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43617.
研究领域:
材料科学
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生物化学
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高影响因子
Small
·
2021
·Vol. 17
·期 10
·2006534
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IF 13.281
Bin Qiao,Ting Yang,Shufeng Shi,Nan Jia,Yu Chen,Xinbing Chen,Zhongwei An,Pei Chen
The efficient electrocatalysts toward the ethylene glycol oxidation reaction (EGOR) are highly desirable for direct ethylene glycol fuel cells because of the sluggish kinetics of anodic EGOR. Herein, porous RhCu nanoboxes are successfully prepared through facile galvanic replacement reaction and succedent sodium borohydride reduction strategy. Benefiting from hierarchical pore structure, RhCu nanoboxes display excellent electrocatalytic performance toward the EGOR in alkaline medium with a mass activity of 775.1 A g Rh −1 , which is 2.8 times as large as that of commercial Rh nanocrystals. Moreover, the long-term stability of RhCu nanoboxes is better than that of commercial Rh nanocrystals. Furthermore, the theoretical calculations demonstrate that RhCu nanoboxes possess lower adsorption energy of CO and lower reaction barrier (0.27 eV) for the CO ads oxidation with aid of the adsorbed OH ads species, resulting in the outstanding electrocatalytic performance toward the EGOR. This work provides a meaningful reference for developing highly effective electrocatalysts toward the EGOR.
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PubMed
高影响因子
JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION
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2021
·
IF 3.517
Chenshu Wang,Lijuan Wang,Xiuzhen Wan,Xuefeng Jiang,Jiang Yuan
A biocompatible hydrogel is ideal for tissue engineering and regeneration. In this study, methacrylated keratin (KerMA) was synthesized for the first time and then blended with poly(ethylene glycol dimethacrylate) (PEGDMA) to form hydrogel through photocrosslinking. The chemical structure, gelation time, swelling behavior, hydrophilicity, cytotoxicity, and 3D printability of PEGDMA/KerMA hydrogels were characterized and exploited. The PEGDMA/KerMA hydrogels performed good cytocompatibility, providing potential applications for tissue engineering and regenerative medicine.
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PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2017
·
IF 2.895
Shurui Xu,Shuanshi Fan,Yanhong Wang,Xuemei Lang
Kinetic hydrate inhibitors (KHIs) combined with thermodynamic inhibitors (THIs) such as monoethylene glycol (MEG) have been good additives for the prevention of hydrate blockages in oil and gas industry operations. The regeneration and recycling of MEG are conventional process steps used to reduce costs. However, the recovery of THIs in the presence of KHIs or the recovery of the KHIs alone has rarely been investigated. In this paper, a series of experiments was designed to study the recovery of both a KHI based poly (N-vinylcaprolactam) and MEG. The results showed that the MEG recovery rate was closely related to the recovery temperature, but was not influenced by the KHI. The MEG recovery rate from solutions consisting of MEG and the KHI was as high as 94.52%, and the KHI was recovered along with the MEG. The polymer structure of the KHI was rarely changed when the recovery temperature was close to its polymerization temperature. The presence of the KHI had a negative impact on the thermodynamic inhibition efficiency of the MEG. The KHI performance of the recovered solution obtained at the KHI polymerization temperature could reach the level of the fresh combination inhibitor, but the recovered solutions obtained at temperatures far above the KHI polymerization temperature demonstrated worse inhibitory performance. The kinetic performance could be restored by adding 5.0 wt% fresh MEG. MEG enabled a subcooling temperature decrease into the range in which KHI which could play its role effectively, leading to the improved kinetic performance of the recovered solution.
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高影响因子
KEY ENGINEERING MATERIALS
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2021
·
IF 0
Yang Yi Chen,Min Pan,Shan Hong Hu,Qi Huan,Chu Yang Zhang
The surface wettability of thermo-responsive random poly (ethylene glycol methyl ether methacrylate-co-triethylene glycol methyl ether methacrylate), abbreviated as P(MEOMA-co-MEO3MA), was investigated in thin film. UV-Vis spectroscopy shows that the LCST of P(MEOMA-co-MEO3MA) with molar ratios of 0:20, 6:14 and 9:11 were 43°C, 32 oC and 25 oC, respectively. LCST shifts towards lower temperature when molar ratio of MEOMA increases. ATR-FTIR indicates that P(MEOMA-co-MEO3MA) thin film experienced a collapse when the temperature passes its LCST. The contact angle of the paraffin oil on the film decreases 15o when the temperature is above its LCST, which confirms the surface wettability can be controlled. Atomic force microscopy shows the surface of the swollen thin film becomes rougher when above it LCST.
研究领域:
材料科学
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高分子化学
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DOI
Advanced Industrial and Engineering Polymer Research
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2019
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IF 0
Han Hu,Ruoyu Zhang,Zhengyang Kong,Kai Wang,Wu Bin Ying,Jinggang Wang,Jin Zhu
Poly (butylene furandicarboxylate) based poly (ether ester), with poly (ethylene glycol) (PEG) molecular weight from 600 to 20 K g mol −1 and mass fraction of hard segments fixed at 50%, are synthesized through transesterification and melt polycondensation. When M n (PEG) is less than 1500 g mol −1 , the copolymers tend to be homogeneous. The tendency of microphase separation is facilitated by the increasing M n (PEG). The mechanical properties and water swelling are influenced by M n (PEG), equilibrium water-uptake and PEG crystals. Elastic modulus of samples with no PEG crystals vary from 34 to 64 MPa, with elongation at break exceeding 1000%. The hydrolytic degradation is strongly affected by M n (PEG), degradation medium and alkalinity. The degradation of copolymers with short PEG (<1500 g mol −1 ) could be accelerated by ions and increasing alkalinity in medium. For copolymers with M n (PEG) from 2 K to 6 K g mol −1 , the degradation rate is relatively slow, due to relatively long PBF segments and improved PBF crystals hindering the hydrolysis of ester bond. For copolyesters of PBF50-PEG10K and 20 K, the oxidation of PEG dominates the degradation behavior while the PBF segments can hardly be damaged. The drastic degradation of these samples takes place in the solutions of pH = 12, suggesting the high alkalinity can break the long PBF segments. The distinct degradation behavior of the copolymers conduces to realize tuned hydrolysis for different biomedical applications.
研究领域:
材料科学
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生物医学工程
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DOI
JOURNAL OF APPLIED POLYMER SCIENCE
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2017
·Vol. 135
·期 9
·45732
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IF 1.86
Xiangke Sun,Xue Liu,Chenglong Li,Yuandou Wang,Li Liu,Feng Su,Suming Li
A series of poly(ɛ-caprolactone)–poly(ethylene glycol) (PCL-PEG) and poly(ɛ-caprolactone/glycolide)–poly(ethylene glycol) [P(CL/GA)-PEG] diblock copolymers were prepared by ring-opening polymerization of ɛ-caprolactone or a mixture of ɛ-caprolactone and glycolide using monomethoxy PEG (mPEG) as macroinitiator and Sn(Oct) 2 as catalyst. The resulting copolymers were characterized using 1 H-NMR, gel permeation chromatography, differential scanning calorimetry, and wide-angle X-ray diffraction. Copolymer micelles were prepared using the nanoprecipitation method. The morphology of the micelles was spherical or worm-like as revealed by transmission electron microscopy, depending on the copolymer composition and the length of the hydrophobic block. Introduction of the glycolide component, even in small amounts (CL/GA = 10), disrupted the chain structure and led to the formation of spherical micelles. Interestingly, the micelle size decreased with the encapsulation of paclitaxel. Micelles prepared from mPEG5000-derived copolymers exhibited better drug loading properties and slower drug release than those from mPEG2000-derived copolymers. Drug release was faster for copolymers with shorter PCL blocks than for those with longer PCL chains. The introduction of glycolide moieties enhanced drug release, but the overall release rate did not exceed 10% in 30 days. In contrast, drug release was enhanced in acidic media. Therefore, these bioresorbable micelles and especially P(CL/GA)-PEG micelles with excellent stability, high drug loading content, and prolonged drug release could be promising for applications as drug carriers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 45732.
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高影响因子
POLYMER SCIENCE SERIES B
·
2022
·Vol. 64
·期 4
·429-444
·
IF 1.023
Juan Chen,Zhang Xiaomei,Chen Yuying,Lin Xing,Jiang Yan,Zhang Hongwen,Liu Hongbo
Abstract — In this article, the octamethylcyclotetrasiloxane is introduced into ethylene glycol. The reaction is terminated using acrylic acid to obtain a linear polydimethylsiloxane intermediate comprising double bonds at the ends. The targeted copolymer is prepared by copolymerizing polydimethylsiloxane intermediate and butyl methacrylate. Additionally, blended-porous film is prepared by adding the copolymer to the cyclodextrin copolymer. The results reveal that the thermal stability of the copolymer increases with the increase of the polydimethylsiloxane content. The ethanol solution of the copolymer of a certain formulation has temperature sensitivity. The contact angle hysteresis of cyclodextrin copolymer is larger on the inclined surface at five degrees from the horizontal, but the blended-porous films all have low contact angle hysteresis, and the minimum contact angle hysteresis decreased to 2°. The main reason for the observed difference is that the presence of the copolymer makes the surface morphology of the film changed greatly. The blended-porous films have a waterproof and easy-to-slide surface.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
SYNTHETIC COMMUNICATIONS
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2017
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IF 1.134
Haifei Zhang,Fengfan Zhu,Yuan Xu,Xiaoxiang Zhang,Xinbao Zhu
The synthesis of several ricinoleic acid glycol ether esters by high-pressure microwave radiation is described. Ricinoleic acid which is from castor oil reacted fastly with glycol ethers in the presence of NaHSO4 · H2O and dichloromethane (DCM) in special microwave reactor. The influences of reaction factors such as catalyst and solvent type, reaction temperature, and time were investigated and the optimal reaction conditions were obtained. The activity of catalyst had a higher performance up to the 10th cycle and the excellent values of turnover numbers and turnover frequency were obtained. Compared with the traditional esterification in reflux heating systems., the microwave-assisted process has many advantages such as shorter reaction time, less side effects, higher yield, which is a great potential for the development of green chemistry.
研究领域:
有机化学
·
绿色化学
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DOI
高影响因子
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