INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Yuanhao Qiu,Dan Xu,Guoqing Sui,Dongdong Wang,Ming Wu,Lipeng Han,Haibo Mu,Jinyou Duan
Biofilms and intracellular bacteria often cause a series of overwhelming public health issues due to their strong drug resistance. Hence, chitosan nanoparticles (CS NPs), phosphatidylcholine and gentamicin were used to synthesize a novel nanodrug delivery system (GPC NPs). Dynamic light scattering (DLS) demonstrated that the surface zeta-potential of GPC NPs was −19.5 mV. The morphology of GPC NPs was observed by scanning electron microscopy (SEM). The gentamicin adsorption and release behaviors of GPC NPs were also investigated. The GPC NPs could effectively damage and remove the biofilm formed by pathogens through permeation of the antibiotic into the biofilm. In addition, the nanoparticles were readily engulfed by macrophages which facilitated the killing of intracellular bacteria and had neglectable cytotoxicity. Our study indicated that GPC NPs could be used as a promising nanoantibacterial agent against biofilms and intracellular bacteria.
研究领域:
药学
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纳米技术
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微生物学
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药物递送系统
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DOI
PubMed
高影响因子
POLYMER BULLETIN
·
2015
·Vol. 72
·期 6
·1531-1543
·
IF 1.438
Zhou Zhihua,Huang Huihua,Huang Tianlong,Peng Cheng,Zhou Hu,Liu Qingquan,Zeng Wennan,Liu Lihua,Cao Dafu,He Siliang,Xiang Liujiao,Yan Hua
Novel maleated poly( d , l -lactide- co -glycolide) (MPLGA) was melt copolymerized directly from maleic anhydride, d,l -lactide and glycolide monomers with stannous octoate as catalyst and benzoyl peroxide as initiator. FTIR, 1 H NMR, GPC and maleation content were employed to qualitatively characterize the synthesized MPLGA. The effects of the catalyst dosage, reaction time and reaction temperature on weight average molecular mass, polydispersity index and maleation content of MPLGA were also investigated. The results indicated that the novel MPLGA was successfully obtained using melting-copolymerization method. MPLGA, with a weight average molecular mass of about 5.39 × 10 4 Da, a polydispersity index of 1.51 and a maleation content of 7.1 wt%, was obtained when polymerization was conducted with catalyst dosage of 0.03 wt% for 36 h at 140 °C. The results indicated that the introduction of maleic anhydride into PLGA may offer new and important options for biomaterial applications.
研究领域:
材料科学
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高分子化学
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生物材料
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DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2022
·
IF 6.206
Junxiang Ma,Kunyi Cai,Chao Yang,Meiqi Li,Xiaopeng Pan,Yi Huang,Juming Yao,Jinhuan Zheng,Jianzhong Shao
A new photocurable coating process that combines ultra violet light emitting diode (UV-LED) and deliberately synthesized photocurable polyurethane acrylate (PUA) was developed in this study. The structures of the PUA were characterized by attenuated total reflectance flourier transformed infrared (ATR-FTIR), porton nuclear magnetic resonance ( 1 H NMR) and gel permeation chromatography (GPC). The structure-activity relationship of such PUA was studied by rheological measurements, photopolymerization performance, and mechanical tests. By adjusting the molecular weight and the number of functional groups in the PUA, balanced the wear resistance and flexibility of the photocured coatings were achieved. The optimal formula for photocurable coating was obtained as follows: the R-value (the molar ratio of –NCO/–OH) of PUA was 1.3, the ratio of PUA/HEA (2-hydroxyethyl acrylate) was 60 wt%/40 wt%, and the ratio of end-capped agent HEA/PETA (pentaerythritol triacrylate) was 2/1. With the optimized photocurable coating formula, textile artificial leathers were fabricated and exhibited excellent colorfastness to rubbing, and Martindale abrasion resistance and satisfied fabric handle.
研究领域:
材料科学
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高分子化学
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纺织工程
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涂层技术
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DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Xu Su,Han Fang,Hao Yang,Fangfang Zou,Gang Li,Lian Wang,Hongxin Liao,Wei Guan,Xuebu Hu
Polysaccharides can be potential binders for lithium-ion batteries due to their strong adhesion through numerous hydroxyl groups . As a novel waterborne lithiated polysaccharide derivative, cellulose sulfate lithium (CSL) is successfully synthesized and used as the binder for LiFePO 4 (LFP) cathode. The chemical structure of CSL is verified by FTIR-ATR, XRD, C 13 -NMR, GPC , EA , ICP and TGA . Compared to LFP cathode using polyvinylidene difluoride binder, electrochemical measurements show that the LFP cathode using CSL (LFP-CSL) has lower polarization and better rate performance owing to higher lithium-ion conductivity of CSL. The result of morphological analysis indicates that CSL binder can maintain an integrated LFP cathode structure during hundreds of cycles. As a result, the LFP-CSL cathode exhibits a discharge capacity of 133.4 mAh g −1 and maintains remarkable cycle stability with retention of 93.1 % after 300 cycles at 1C. These findings provide novel insights into the rational design of the binders for the LFP cathode.
研究领域:
材料科学
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电化学
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能源存储
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DOI
PubMed
高影响因子
ADVANCES IN POLYMER TECHNOLOGY
·
2017
·Vol. 37
·期 7
·2561-2567
·
IF 1.291
Jikai Pei,Ziwei Wang,Jianguo Ren,Diansheng Liu
In this paper, an acrylic acid-rich wastewater from the production of propylene to acrolein was used to synthesize the polycarboxylate superplasticizers. First, the acrylic acid-rich wastewater was oxidized. Then, two kinds of unsaturated polyether macromonomers {methallyl polyethylene glycol (HPEG) and isoprenol polyethylene glycol (IPEG)} and the oxidized wastewater were copolymerized with it, respectively, by free radical polymerization in aqueous solution. The monomer conversion, molecular weight, molecular weight distribution of the copolymers of gel permeation chromatography (GPC) were characterized. The performance of the two copolymers was characterized by measuring paste flow, adsorption using GPC method, and the applied behavior of premixed concrete. The results showed that the synthesized copolymers could meet the requirement of application in contrast to the commodity product.
研究领域:
化学工程
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材料科学
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环境科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2021
·
IF 7.033
Xiangchen Kong,Chao Liu,Weicong Xu,Yue Han,Yuyang Fan,Ming Lei,Ming Li,Rui Xiao
Stubborn lignin (SL) is the thermochemically stable fragment generated from biomass utilization (e.g., pyrolysis , hydrolysis, fermentation, pulping), which is comparatively difficult to be further depolymerized into value-added bio-products. The cleavage of the stubborn linkages within the structure of SL, such as C C, α -O-4, and 4-O-5 linkages, is the key for its valorization. Herein, we investigated the depolymerization of SL through catalytic hydroprocessing in supercritical methanol with Cu/CuMgAlO x catalyst. The yield of monomers reached 37.76C% with 240 min at 300 °C. Cyclohexanols were identified as the major monomeric products, indicating the occurrence of hydrodeoxygenation and hydrogenation. GPC , quantitative 13 C NMR, HSQC NMR, and HMBC NMR analyses evidenced the depolymerization of SL and upgrading of its derivatives. Furthermore, the mechanistic studies were carried out to provide insights to the stubborn linkage cleavages. The degrees of difficulty to break up the three involved linkages obeyed the sequence of β -5 > 4-O-5 > α -O-4. The apparent activating energies ( E a ), chemisorption energies ( E c ), and bond dissociation energies (BDE) were determined computationally to support the experimental results from the perspectives of kinetics, chemisorption, and thermodynamics, respectively. This research provides a reliable way for the utilization of SL.
研究领域:
化学工程
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催化
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生物化学
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可再生能源
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Yankun Xie,Weiqu Liu,Liyan Liang,Chunhua Liu,Sha He,Fengyuan Zhang,Hongyi Shi,Maiping Yang
In this study, in order to improve the hydrophobicity and corrosion protection of epoxy coatings, a fluorinated polyacrylate polymer containing epoxy groups (PFEMA) was designed and used to modify epoxy resin . FT-IR, 1 H-NMR and GPC were employed to characterize the structure of PFEMA polymer. Contact angle (CA), X-ray photoelectron spectrum (XPS), scanning electron microscope , Tafel curves, electrochemical impedance spectroscopy (EIS) and salt spray test were carried out to investigate the performance of fluorinated polyacrylate modified epoxy coatings. The incorporation of PFEMA polymer changes the hydrophilic nature of epoxy resin to hydrophobicity, and the CA shifts from 67° to 98° with the content of fluorinated polyacrylate increases from 0 to 10 wt%. EIS measurements show that the impedance modulus value of fluorinated epoxy coatings is higher compared to pure epoxy resin. Additionally, the corrosion rate also decreases and its value shifts from 4.223×10 −8 mm/year to the lowest value of 9.696×10 -9 mm/year with the increasing of fluorinated polyacrylate in epoxy resin, demonstrating that the corrosion resistance of epoxy coatings has been significantly strengthened after introduction of fluorinated polyacrylate.
研究领域:
材料科学
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腐蚀科学
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表面化学
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高分子科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Binbin Dong,Zong Hou,Zhong Zheng,Junpeng Xing,Ningning Zhao,Zhiqiang Liu,Shu Liu
The abundant ginseng neutral polysaccharide (GPN) has been neglected due to its lower activity compared to acidic polysaccharide in ginseng. Herein, the composite enzymes were used to modify the GPN and obtained the enzymatic-degradation-GPN (EGPN). The structural changes were further characterized by GPC, FT-IR, Congo red, XRD, zeta potential, TG, cryo-SEM and AFM. The antioxidant activity of GPNs in vitro was investigated by in vitro chemical experiments and oxidative stress-related indicators on PC12 cells damaged by Aβ 25 – 35 , and EGPN showed favorable antioxidant activity. In addition, EGPN metabolized by intestinal microbiota also significantly increased the viability of injured PC12 cells. Furthermore, in vitro fermentation model was used to investigate the differences of physicochemical properties of GPNs and their regulatory effects on the microbiota. EGPN enhanced the diversity of the microbiota and increased the concentration of short-chain fatty acids (SCFAs). Importantly, EGPN demonstrated a significant reduction in the presence of detrimental bacteria such as Enterococcus and Allobaculum , while simultaneously promoting the growth of beneficial microorganisms including Lactobacillus , Prevotella , and Ruminococcu . This study highlights the potential use of EGPN prepared by composite enzymatic degradation in antioxidant, neuroprotection and restoration of intestinal homeostasis.
研究领域:
药理学
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生物化学
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微生物学
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神经科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2018
·
IF 3.468
Chuanchuan Liu,Qiang Yao
The thermal degradation of resorcinol bis(diphenyl phosphate) (RDP) and bisphenol A bis(diphenyl phosphate) (BDP) has been studied by 31 P NMR, Q-TOF, and GPC at normal and extreme heating conditions. The thermal degradation begins with the elimination reaction that generates reactive monomers and arynes. The aryne-bisphosphate adducts or their decomposition products were identified through Q-TOF analysis. Through the intertwined condensations, transesterifications, and elimination reactions, the reactive acid phosphates are formed and eventually convert the bisphosphates into volatile triphenyl phosphate, oligomeric aryl/acid polyphosphates, and non-volatile polyphosphoric acid. It is these reactions and products that provide the bisphosphates effective pathways for entry into the vapor phase or action in the condensed phase. The facility of these reactions, particularly the elimination reaction that is the initiation step, to occur is critical for the high efficiency of flame retardancy displayed by the bisphosphates. A thermal Melvin rearrangement of the bisphosphates to arylphosphonates has also been established.
研究领域:
材料科学
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化学
·
高分子科学
·
分析化学
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产品关联
DOI
高影响因子
POLYMER
·
2011
·
IF 3.829
Zhuan Yi,Liping Zhu,Liang Cheng,Baoku Zhu,Youyi Xu
An amino-substituted polyethersulfone (PES) was synthesized by the polycondensation of a functional monomer bis(3-amino-4-hydroxyphenyl) sulfone with bis(4-fluorophenyl) sulfone. The amine groups incorporated into PES were employed as anchors to immobilize the chain transfer agents of reversible addition-fragmentation polymerization (RAFT). The resultant macro chain transfer agent was used to initiate the polymerization of the hydrophilic monomers N -isopropyl acrylamino (NIPAAm) and N, N -dimethylamino-2-ethyl methacrylate (DMAEMA), respectively. The gel permeation chromatography (GPC) results confirmed the successful synthesis of the amphiphilic copolymers PES- g -PNIPAAm and PES- g -PDMAEMA, and these two copolymers were perhaps the few examples of amphiphilic copolymer synthesized via a radical polymerization from PES main chains. The amino-substituted PES seemed a versatile precursor that showed a potential of functionalization via various strategies including click chemistry, atom transfer radical polymerization and RAFT polymerization. The synthesized amphiphilic copolymers were finally used as additives to improve the hydrophilicity and the filtration performances of PES membranes.
研究领域:
高分子化学
·
材料科学
·
膜技术
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产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Shiyun Zhou,Tian Xia,Shuo Wu,Wanting Zhang,Jianhui Xu,Yi Yang,Youbing Li,Guangxian Li
Self-healing bitumen can significantly enhance the durability and service life of bituminous pavement, thereby reducing the need for frequent maintenance and repairs. In this study, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), and isophorone diamine (IPDA) were utilized to design asymmetric dynamic hard segments, imparting self-healing properties to polyurethane even at room temperature. Particular emphasis was placed on hydrogen bonding, as its reversible formation serves as a primary mechanism for the self-healing characteristics of the material. During the synthesis of polyurethane (PU), two different composition ratios were employed to produce two types of PU with distinct chemical structures, molecular weights, and dynamic crosslink densities, which were characterized using NMR, FTIR, GPC, and DMA, respectively. Furthermore, these two PU types exhibited varying mechanical properties and glass transition temperatures, leading to differences in the rheological properties of the corresponding PU-modified bitumen. Dynamic frequency sweep test results indicated that bitumen modified with PU exhibiting higher molecular weight and narrower molecular weight distribution had superior rutting resistance and enhanced room-temperature self-healing capabilities. The underlying reasons for this improvement can be attributed to the hydrogen bonding present in the PU as well as the phase separation structure between the PU and bitumen.
研究领域:
材料科学
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高分子化学
·
土木工程
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DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2016
·Vol. 35
·期 1
·54-65
·
IF 1.811
Chen Qi-jing,An Ze-sheng
A series of well-defined core cross-linked star (CCS) polymeric ionic liquids (PILs) were synthesized via a three-step approach. First, the styrenic imidazole-based CCS polymer (S-PVBnIm) was prepared by the RAFT-mediated heterogeneous polymerization in a water/ethanol solution, followed by the quaternization of S-PVBnIm with bromoalkanes and anion exchange. The CCS polymers were characterized by gel permeation chromatography (GPC), nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The obtained CCS polymers were used as the effective emulsifiers for oil-in-water high internal phase emulsions (HIPEs). Multiple oils with different polarity including n -dodecane, undecanol, toluene and octanol were emulsified using 0.5 wt% S-PVBnIm aqueous solution under the acidic condition to form HIPEs with long-term stabilities. The excellent emulsification properties of CCS PILs were demonstrated by HIPE formation for a variety of oils. The properties of HIPEs in terms of emulsion type and oil droplet size were characterized by the confocal laser scanning microscopy (CLSM). The intriguing capability of CCS PILs to stabilize HIPEs of various oils holds great potentials for the practical applications.
研究领域:
聚合物化学
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材料科学
·
胶体与表面化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）