JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2019
·Vol. 57
·期 19
·2030-2037
·
IF 2.591
Muhammad Waqas Ali,Siyuan Cheng,Jianhao Si,Muhammad Siddiq,Xiaodong Ye
Hyperbranched poly(2-ethyl-2-oxazoline) was synthesized by a combination of cationic ring-opening polymerization and the oxidation of thiol to disulfide groups. A three-arm star poly(2-ethyl-2-oxazoline) (PEtOx) was first synthesized using 1,3,5-tris(bromomethyl) benzene as an initiator. The star PEtOx was end-capped with potassium ethyl xanthate. Similarly, a linear PEtOx was synthesized and end-capped with potassium ethyl xanthate using benzyl bromide as an initiator. Hyperbranched PEtOx was then obtained by in situ cleaving and subsequent oxidation of the star PEtOx and linear PEtOx mixture with n -butylamine as both a cleaving agent and a base in tetrahydrofuran. The linear PEtOx was used to prevent the formation of gel. The hyperbranched PEtOx can be cleaved with dithiothreitol to trithiol and monothiol polymer. The hyperbranched PEtOx shows no remaining thiols using Ellman's assay. The resulting hyperbranched PEtOx was hydrolyzed to a novel hyperbranched polyethyleneimine with degradable disulfide linkages. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2030–2037
研究领域:
高分子化学
·
材料科学
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DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 17
·3510
·
IF 5
Na Su
The paper reports a facile synthesis of novel anionic spherical polymer brushes which was based on grafting sodium 2-acrylamido-2-methylpropane-1-sulfonate from the surface of 4,4′-Azobis (4-cyanopentanoyl chloride)-modified carbon spheres. Various characterization methods involving a scanning electron microscope, energy dispersive X-ray spectroscopy, Fourier transform infrared spectrum, and thermo-gravimetric analysis were utilized to analyze the morphology, chemical composition, bonding structure, and thermal stability, respectively. The molecular weight (Mw) and polydispersity (Mw/Mn) of brushes were 616,000 g/mol and 1.72 determined by gel permeation chromatography experiments. Moreover, the dispersibility of ASPB in water and in the presence of aqueous NaCl solutions of different concentrations was investigated. Results show that the dispersibility of carbon spheres has been enhanced owing to grafted polyelectrolyte chains, while the zeta potential of the particle decreases and its brush layer shrinks upon exposure to sodium ions (Na+).Keywords:carbon spheres;anionic spherical brushes;surface-initiated polymerization;NaAMPS
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PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 11
·4701-4716
·
IF 3.553
Ma Jianfeng,Zhao Hongxia,Shang Yazhuo,Peng Changjun,Liu Honglai,Zheng Shuzhen,Wang Tao,Qi Shuai,Ran Qianping
Abstract The presence of a highly alkaline environment or large amounts of Ca 2+ in concrete exerts a great influence on the dispersion of graphene oxide (GO) particles. Therefore, the development of a highly efficient GO dispersant to adapt to complex concrete environments is important. In this work, novel phosphate-modified small molecular polydentate polymers were synthesized and used as efficient dispersants for cement and high-concentration GO solutions. The chemical structure of the polymers was confirmed by 1 H NMR and IR spectroscopy, and the effect of adsorption groups on the adsorption ability of polymers was studied by using adsorption experiments and theoretical calculations. Results showed that the dispersant inositol hexaphosphate–methoxy polyether (IHP-MP) features a high adsorption equilibrium constant and strong adsorption ability. IHP-MP exhibited not only good water-reducing and slump-retaining properties but also remarkable cement hydration-retarding effects due to its numerous phosphate groups. IHP-MP could be used as an auxiliary GO dispersant with the comb polymer PCE to effectively reduce the viscosity and improve the stability of GO solutions. SEM, TGA and IR characterization indicated that IHP-MP strongly interacts with the surface groups of GO particles. Graphic Abstract
研究领域:
材料科学
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化学工程
·
聚合物化学
·
土木工程
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高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2023
·Vol. 225
·期 5
·2300361
·
IF 2.5
Dan Liu,Hui Liang,Jiang Lu
A novel monomer, N -(2-((3-morpholine-3-isopropyl)thio)ethyl)methacrylamide (MTMA), is synthesized and polymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization to give a thermoresponsive polymer poly[ N -(2-((3-morpholino-3-oxopropyl)thio)ethyl)methacrylamide] (PMTMA). PMTMA exhibits reversible thermoresponsive phase transitions of the lower critical solution temperature (LCST) type in water and the upper critical solution temperature (UCST) type in ethanol and methanol. The degree of polymerization and concentration of PMTMA, and solvent type have a significant influence on the transition temperature. PMTMA shows complicated thermoresponse in water–alcohol mixtures. In water–ethanol mixtures, the phase diagram of PMTMA can be divided into three regions according to ethanol volume percentages, φ : 0 ≤ φ < 15% for an LCST region; 15% ≤ φ < 91.5% for a complete dissolution region; 91.5% ≤ φ ≤ 100% for a UCST region. At high water content, the LCST increases with increasing ethanol content; and at high ethanol content, the UCST decreases with increasing water content. In water–methanol mixtures, PMTMA shows more complex thermoresponse. In the range of 0–50 °C, the phase diagram can be divided into five regions, depending on the methanol volume percentages φ : 0 ≤ φ < 15% for LCST region; 15% ≤ φ < 25% for immiscible region; 25% ≤ φ < 85% for UCST region; 85% ≤ φ < 95% for fully dissolved region; 95% ≤ φ ≤ 100% for another UCST region.
研究领域:
高分子化学
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材料科学
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物理化学
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高影响因子
International Journal of Greenhouse Gas Control
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2014
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IF 3.821
Chao Guo,Shaoyun Chen,Yongchun Zhang
Quantitative 13 C nuclear magnetic resonance (NMR) spectroscopy was used to study carbon dioxide (CO 2 ) absorption and desorption, at 313 and 393 K, respectively, from 30 wt% aqueous 2-(2-aminoethylamine)ethanol (AEEA), 30 wt% 2-amino-2-methyl-1-propanol (AMP) and 20 wt% AEEA + 10 wt% AMP solutions. The 13 C NMR results indicate that the main AEEA species are free amine, protonated amine, primary carbamate and secondary carbamate, and the main AMP species are free amine and protonated amine. There is no evident indication that dicarbamate species of AEEA and carbamate of AMP are formed. When AEEA absorbs CO 2 , the formation of AEEA carbamate on primary amine is comparatively faster than that on secondary amine. During the CO 2 desorption process, the AEEA carbamate on secondary amine is produced by an endothermic reaction, which reduces the overall efficiency of desorption. Six cycles of absorption–desorption tests are performed to measure the feasibility of regenerated amine solutions for reuse and the absorption amount of them remains essentially constant during the second to the sixth absorption–desorption experiments. Compared with pure AEEA solution, the recyclability of blended amines, AEEA + AMP, improves while the mol CO 2 /mol amine (CO 2 loading) of the blended amines decreases.
研究领域:
化学工程
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环境化学
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碳捕集与封存（CCS）
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物理化学
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核磁共振（NMR）波谱学
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高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2020
·
IF 5.065
Yu Dong,Xin Yin,Yapeng Cao,Shufeng Shen
Water-lean absorbent has great potential in energy savings over aqueous amines for CO 2 capture. Measurements on density and viscosity for the ternary systems of monoethanolamine (MEA), 2-(methylamino)ethanol (MAE), 2-(ethylamino)ethanol (EAE) or 2-(butylamino)ethanol (BAE) + 2-butoxyethanol (EGBE) + water have been performed at atmospheric pressure and temperatures from 293.15 to 353.15 K. The total amine concentrations in these systems were held at two constant mass fractions in the range of 30-60 mass%. Excess molar volume ( V E ) and viscosity deviation (Δ η ) of the ternary systems were also derived from the experimental data and correlated with Cibulka parameters with the aid of Redlich-Kister equation to fit the measured ternary properties from their pure components. The addition of water into the binary (amine +EGBE) systems can affect greatly the molecular interactions . The V E values of the ternary blends are found to be negative over the investigated conditions. However, Δ η values are observed to be positive except in the rich (amine + EGBE) concentration region. The variations of V E and Δ η were represented and interpreted with molecular interactions and structural effects.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Ying Xu,Jing Yang,Xiongyan Meng,Shuai Meng,Tiantian Sun,Ning Ding,Chengli Zong
Covalently linking an adjuvant to an antigenic protein enhances its immunogenicity by ensuring a synergistic delivery to the immune system, fostering a more robust and targeted immune response. Most adjuvant-protein conjugate vaccines incorporate only one adjuvant due to the difficulties in its synthesis. However, there is a growing interest in developing vaccines with multiple adjuvants designed to elicit a more robust and targeted immune response by engaging different aspects of the immune system for complex diseases where traditional vaccines fall short. Here, we pioneer the synthesis of a dual-adjuvants protein conjugate Vaccine 1 by assembling a toll-like receptor 7/8 (TLR7/8) agonist, an invariant natural killer T cell (iNKT) agonist with a clickable bicyclononyne (BCN). The BCN group can bio-orthogonally react with azide-modified severe acute respiratory syndrome coronavirus-2 receptor-binding domain (SARS-CoV-2 RBD) trimer antigen to give the three-component Vaccine 1 . Notably, with a mere 3 μg antigen, it elicited a balanced subclass of IgG titers and 20-fold more IgG2a than control vaccines, highlighting its potential for enhancing antibody-dependent cellular cytotoxicity. This strategy provides a practicable way to synthesize covalently linked dual immunostimulants. It expands the fully synthetic self-adjuvant protein vaccine that uses a single adjuvant to include two different types of adjuvants.
研究领域:
免疫学
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病毒学
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药物化学
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疫苗研发
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高影响因子
Nutrients
·
2024
·Vol. 16
·期 4
·514
·
IF 4.8
Xiao Wang,Yongjie Liang,Bohan Zhang,Lixin He,Wenxuan Li,Wenwen Zhang,Chengzong Li,Lihong Luo,Talha Umar,Huili Feng,Changwei Qiu
2’-Hydroxychalcone is a hydroxyl derivative of chalcones, which are biosynthetic precursors of flavonoids and rich in the human diet. The anticancer activity of 2’-hydroxychalcone has been reported in several cancers but remains to be investigated in breast cancer. In the current study, 2’-hydroxychalcone showed significant cytotoxicity against breast cancer cell lines MCF-7 and CMT-1211. It could inhibit breast cancer cell proliferation, migration, and invasion in vitro and suppress tumor growth and metastasis in vivo. Mechanistic investigation revealed that the NF-κB pathway was significantly inhibited by 2’-hydroxychalcone treatment accompanied by an excessive intracellular accumulation of reactive oxygen species, induction of endoplasmic reticulum stress, and activation of JNK/MAPK. In addition, 2’-hydroxychalcone elevated the autophagic levels in breast cancer cells equipped with increasing numbers of autophagy vesicles and complete autophagic flux. Finally, autophagy-dependent apoptosis was observed in 2’-hydroxychalcone-induced cell death. In conclusion, 2’-hydroxychalcone enhances the autophagic levels and induces apoptosis in breast cancer cells, which could be contributed to the inhibition of the pro-survival NF-κB signaling, indicating a promising potential for 2’-hydroxychalcone in future anticancer drug development.
研究领域:
肿瘤学
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药理学
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细胞生物学
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分子生物学
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DOI
PubMed
高影响因子
JOURNAL OF COORDINATION CHEMISTRY
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2018
·
IF 1.703
Kuan-Guan Liu,Ru Wang,Hong-Yan Han,Qi-De Shan,Jing Nie,Xiao-Wei Yan
Incorporating ferrocenecarboxylato(-1) into [CuI
2(μ-dppm)2]2+ (dppm = bis(diphenylphosphino)methane) led to the isolation of a heterometallic complex [Cu2(μ2-η1,η1dppm)2(μ2-η1, η1FcCOO)(CH3CN)]BF4·CH3CN (1). It was characterized by infrared spectroscopy (IR), elemental analysis (EA), powder X-ray diffraction analysis (PXRD), ultraviolet–visible spectrum (UV–Vis), nuclear magnetic resonance (NMR), and thermogravimetric analysis (TGA). Single-crystal X-ray structural analysis revealed that ferrocenecarboxylato(-1) coordinated to the [Cu2(μ2-η1,η1dppm)2]2+ unit via μ2-η1,η1 bridging mode in 1. The title complex shows good optical absorption and thermal stability, and reliable electrochemical stability. Moreover, this heterometallic copper(I) complex could be used as a promising electrochemical sensing material for the detection of H2O2.
研究领域:
化学
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材料科学
·
分析化学
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DOI
高影响因子
DYES AND PIGMENTS
·
2020
·
IF 4.613
Yujie Zhang,Xinjiang Shi,Sixuan Xiao,Debao Xiao
Electrochromic devices (ECDs) which able to absorb the solar spectrum of visible (400–780 nm) and infrared (780–2000 nm) have attracted considerable attention due to the light control and energy-saving properties. In this paper, a electrochromic derived derivative of viologens, bis (2-(2-(2-hydroxyethoxy)ethoxy)ethyl) viologen bromide (HEV 2+ 2Br − ) was successfully synthesized and added to novel environmentally benign hydrogel electrolytes containg deionized water , sodium carboxymethyl chitosan and vitamin C (as electron mediators for the first time) as an electrochromic chromophore . The electrochromic devices on the basic of electrochromic materials (HEV 2+ 2Br − ) and hydrogel electrolytes underwent reversible switching between colorlessness and deep purple hues upon the potential ranges from 0 V to −1.2 V. Spectroelectrochemical studies demonstrated that HEV-based gel devices showed exceptional electrochromic behaviors with low driving voltage of −0.80 V, satisfactory optical contrast (unambiguously exceeded 64.13%) and high coloration efficiency (up to 243 cm 2 /C at 520 nm and 119 cm 2 /C at 865 nm) in the visible and infrared radiation. In consideration of their good electrochromic performance and environmentally friendly properties of benign hydrogel electrolytes containing HEV, the HEV-based gel devices have brilliant potentialities as candidates for related electrochromic applications for energy-efficient architecture.
研究领域:
材料科学
·
能源技术
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高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2023
·
IF 5.2
Yanyang Wu,Jiabo Rao,Qing Yi,Zhihui Ma,Bin Wu,Kui Chen,Lijun Ji
Metal-organic frameworks (MOFs) with sensitive nanospace and selective binding sites are widely used to discriminate the subtle structural. Adsorption performances of 2-Phenylethanol, 1-Phenyl-2-propanol, and 2-Ethylphenol on MOFs were studied in this paper. Eight MOFs were prepared hydrothermally and NH 2 -UiO-66(1) was chosen as the subsequent adsorbent based on the larger selectivity for both 1-Phenyl-2-propanol/2-Phenylethanol and 2-Ethylphenol/2-Phenylethanol. Studies on adsorption kinetics showed that pseudo-first-order model was suitable for adsorption performances of 1-Phenyl-2-propanol on NH 2 -UiO-66(1), while pseudo-second-order model was suitable for both 2-Phenylethanol and 2-Ethylphenol. The adsorption isotherm revealed that Langmuir model was suitable for 1-Phenyl-2-propanol, 2-Ethylphenol, and 2-Phenylethanol. Thermodynamic parameters including Gibbs free energy, enthalpy, and entropy indicated that adsorption of 1-Phenyl-2-propanol on NH 2 -UiO-66(1) was a spontaneous and exothermic physisorption process, while those of 2-Ethylphenol and 2-Phenylethanol were spontaneous and endothermic physisorption processes. The adsorption process indicated that the separation of 2-Phenylethanol from 1-Phenyl-2-propanol and 2-Ethylphenol on NH 2 -UiO-66(1) was due to the Lewis acid-base interactions and sieving effect. NH 2 -UiO-66(1) was also treated the simulated enriched 2-Phenylethanol solutions and 99.5% 2-Phenylethanol was obtained. In conclusion, NH 2 -UiO-66(1) can be a feasible adsorbent to separate 2-Phenylethanol from 1-Phenyl-2-propanol and 2-Ethylphenol for industrial application.
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高影响因子
OPTIK
·
2013
·
IF 0.524
Zhijuan Cao,Fengxian Qiu,Qing Wang,Guorong Cao,Lin Zhuang,Qiang Shen,Xiaolong Xu,Jie Wang,Qian Chen,Dongya Yang
The azo benzothiazole polyurethane–urea (ABPUU) was synthesized from chromophore molecule 4-[(6-nitrobenzothiazole-2-yl)diazenyl]phenyl-1,3-diamine NBDPD, polyether polyol (NJ-210) and isophorone diisocyanate (IPDI). The structure, thermal property , mechanical property and physical property were characterized and investigated. The refractive index ( n ) and thermo-optic coefficient (d n /d T ) of ABPUU was determined at different temperature and wavelength (532 nm, 650 nm and 850 nm) using attenuated total reflection (ATR) technique. Using the CCD digital imaging devices, transmission loss of ABPUU was measured. A 1 × 2 Y-branched and 2 × 2 Mach–Zehnder interferometer (MZI) switch with two rib waveguides , dual driving electrodes and two critical 3-dB couplers polymeric thermo-optic switches based on thermo-optic effect of prepared ABPUU were designed and simulation. The power consumption of the Y-branched switch is less than 0.84 mW. The Y-branched and MZI switching rising and falling times obtained are 0.8 ms and 0.2 ms, respectively.
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高影响因子
危险品化学品经营许可证（带存储）