INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2023
·
IF 4.2
Lixin Xing,Jianliang Qin,Jiaming Wang,Kuandi Wang,Hanli Wang,Zhendong Yang,Gaohong He,Xuehua Ruan
Membrane technology, especially the options using highly selective and permeable materials, is the preferred alternative to conduct direct helium enrichment from natural gas. In this work, the monomers containing multiple trifluoromethyl groups, including 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and 2,2′-bis(trifluoromethyl) benzidine (TFMB), are used to synthesize specific polyimide materials. On the one hand, fluorine element can impair affinity to methane and then enhance the selective sorption for helium. On the other hand, trifluoromethyl groups have appropriate steric hindrance to increase accessible volume for helium permeation; moreover, this steric hindrance can make the chain segments more rigid to decrease temporary large-size cavities and then hinder methane permeation. The separation tests revealed that helium permeability is up to 73 Barrer, and its selectivity against methane is up to 247 in this synthesized material after aging and compacting sufficiently. On the whole, the 6FDA-TFMB polyimide materials should be highly promising for membrane-based helium enrichment.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2018
·Vol. 41
·期 10
·2110-2118
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IF 2.415
Wenjie Zhao,Xuhua Lou,Jizhao Guo,Peijian Sun,Yunzhen Jia,Limei Zheng,Lijun He,Shusheng Zhang
Two reversed-phase/anion-exchange mixed-mode stationary phases for high-performance liquid chromatography using calixtriazines as chromatographic ligands were investigated with Tanaka test solutes, monosubstituted benzenes, aromatic positional isomers, and inorganic anions. Calixtriazine as a chromatographic ligand has been reported previously, but the benzylated nitrogen-bridged calixtriazine-bonded silica gel reported in this study is new. The experimental data showed that the calixtriazine platform is a unique chromatographic selector because its multiple active sites are available for different solutes and its chromatographic selectivity could be tuned by introducing substituent on the bridging nitrogen atoms present in the calixtriazine matrix. The synergistic effects of aromatic rings, nitrogen atoms, benzyl groups, and tunable cavity in the host molecule influenced the separation selectivity by multiple retention mechanisms. Such hybrid stationary phases provide more versatility and have great potential in the analysis of complex samples. Moreover, the synthetic protocols presented herein may provide an alternative understanding on macrocyclic host–guest chemistry, leading to new and selective separation media.
研究领域:
分析化学
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色谱技术
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DOI
PubMed
高影响因子
MACROMOLECULES
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2022
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IF 6.057
Xin Ning Zhang,Cong Du,Yan Jie Wang,Li Xin Hou,Miao Du,Qiang Zheng,Zi Liang Wu
The molecular chemical structure has a decisive influence on physicochemical properties of polymer materials, which becomes more complex for hydrogels with dense associative interactions. Recently, we have developed a series of tough supramolecular hydrogels with robust hydrogen-bond associations, and the properties of gels severely depend on the composition of copolymers. Here, we examine the influence of the molecular structure on the mechanical and viscoelastic behaviors of these supramolecular hydrogels synthesized from copolymerization of acrylamide/methacrylamide and acrylic acid/methacrylic acid with a varied α-methyl group on the basic unit. The obtained four kinds of the as-prepared hydrogels exhibit distinct mechanical performances and dynamics, evolving from elastic to glassy state with the increase in the number of α-methyl groups. Rheological dynamic spectra of these hydrogels follow the time–temperature superposition principle, which are used to elucidate the correlation between the chemical structure and the dynamics of gel materials. The incorporation of a hydrophobic α-methyl group effectively improves the chain rigidity and enhances the hydrogen-bond associations. Furthermore, the methyl group on the carboxylic acid unit strengthens the hydrogels more significantly than that on the acrylamide unit, which also results in distinct stability of the hydrogels in water. This comparative study discloses the effect of the α-methyl group on the dynamics of associative copolymers and the performances of supramolecular hydrogels, which should be informative to understand the structure–property relationship of other tough soft materials with associative interactions.
研究领域:
材料科学
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高分子化学
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软物质物理
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DOI
高影响因子
MACROMOLECULES
·
2024
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IF 5.1
Zhiye Yuan,Yijie Jin,Yu Wu,Xinjun Wu,Nan Hai,Jianlei Lu,Chuanzhuang Zhao,Jiawei Zhang
The properties of intelligent polymeric materials are essentially determined by their chemical structures. Shape memory hydrogels that utilize hydrophobic aggregation at elevated temperatures to stabilize temporary shapes, the association of polymer networks is similar to that of thermoresponsive polymers. To realize a precise control on the shape memory function of these materials and broaden their practical applications, it is essential to build up a structure–property relationship on a molecular level. In this study, we fabricated a series of poly(acrylic acid–methacrylic acid)/Ca(CH3COO)2 shape memory hydrogels with cooling-induced shape transformation behavior. The results showed that the incorporation of α-methyl groups would restrict the hydrophobic aggregation of hydrogel networks, and the soft-to-stiff transition temperature of the hydrogels would shift to elevated temperatures with the increasing density of α-methyl groups. Therefore, the shape recovery process could be regulated by adjusting the association degree of the polymer networks. Finally, the hydrogels were explored as smart capsules with sequential drug delivery capacity and as dredging devices capable of removing thrombus. This study reveals the influence of α-methyl groups on the association dynamics of the poly(acrylic acid–methacrylic acid)/Ca(CH3COO)2 hydrogels, which would promote the design of novel shape memory polymers guided by the relationship between chemical structure and properties.
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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 8
·
IF 1.866
Jianwei Li,Guangcheng Zhang,Qi Zhu,Jiantong Li,Hongming Zhang,Zhanxin Jing
In this research, a series of porous copolyimide (co-PI) films containing trifluoromethyl group (CF 3 ) were facilely prepared via a phase separation process. The co-PI were synthesized by the reaction of benzophenone-3,3′,4,4′-tetracarboxylic dianhydride (BTDA) with two diamines of 4,4′-diaminodiphenyl ether (ODA) and 3-trifluoromethyl-4,4'-diaminodiphenyl ether (FODA) with various molar ratios. The flexible and tough porous co-PI films with about 300 μm thickness and 8∼10 μm average diameter could be obtained by solution casting conveniently. The thermal properties of the obtained porous co-PI films were excellent with a glass transition temperature at 270 °C ∼ 280 °C and only 5% weight loss in temperature from 530 °C to 560 °C under nitrogen atmosphere. In addition, the dielectric and hydrophobic properties of porous co-PI films were remarkably improved owing to the presence of trifluoromethyl groups (CF 3 ) in the polymer chains. Moreover, our synthesized porous co-PI films also showed good mechanical properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44494.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 15
·e202406023
·
IF 2
Leyao Chen,Nuoya Wang,Xiaoyu Chang,Ruiyong Wang
Graphical This work investigated the inhibition of 4-thiazolidinone derivatives on SARS-CoV-2 Mpro using enzyme assays, spectroscopy, and molecular docking. Compound 3a showed the best inhibition (IC 50 = 2.36 ± 0.36 µM, K i = 1.72 µM), and the trifluoromethyl group in 3a played an important role. Hydrogen bonding and van der Waals forces were the main forces for the binding. This work provided clues for Mpro inhibitor development. Since the outbreak of COVID-19, one of the strategies used to search for potential drugs has been to screen inhibitors of SARS-CoV-2 Mpro. This work investigated the inhibitory effects of 4-thiazolidinone derivatives on main protease (Mpro) using various methods, including enzyme activity assays, enzyme kinetics, spectroscopy experiments, molecular docking simulations, microscale thermophoresis, and cytotoxicity tests. Compound 3a demonstrated the best inhibition effect among the compounds tested, with IC 50 = 2.36 ± 0.36 µM and K i = 1.72 µM. The trifluoromethyl group in 3a might enhance its inhibition ability. Interactions between the 4-thiazolidinone derivatives and Mpro resulted in fluorescence quenching primarily through static quenching. Thermodynamic analysis indicated that the interaction forces are mainly hydrogen bonds and van der Waals forces. Spectral results revealed that the 4-thiazolidinone derivatives affected the microenvironment of aromatic amino acid residues in Mpro and altered its secondary structure. Differential scanning fluorimetry was used to confirm the interaction between the 4-thiazolidinone derivatives and Mpro. Results of microscale thermophoresis indicated that the K d between 3a and Mpro was 1.56 ± 0.24 µM. Molecular docking simulations provided a more intuitive visualization of the interaction forces. This study provides clues for screening novel Mpro inhibitors.
研究领域:
病毒学
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药物化学
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分子生物学
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高影响因子
CHEMISTRY & BIODIVERSITY
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2020
·Vol. 17
·期 9
·e2000066
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IF 2.039
Zhiguo Mang,Shuai Zhang,Jing Bai,Meijuan Li,Hao Li
Structural simplification and modification of natural products are always very important resources to antitumor drugs. By introducing various aminomethyl groups and amide groups into the phenanthrene ring of tylophorine, a novel series of tylophorine derivatives have been designed and synthesized, and their antiproliferative activities against MCF-7, A549 and HepG-2 cells have been evaluated, too. The results indicated that most of the prepared compounds exhibited good antitumor activities. Especially, one compound with an {ethyl[2-(morpholin-4-yl)ethyl]amino}methyl group at the side chain exhibited the most significant cytotoxic effects.
研究领域:
肿瘤学
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药物化学
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天然产物研究
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DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE
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2021
·Vol. 59
·期 15
·1701-1710
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IF 0
Jianlei Lu,Xionglin Zhou,Jialin Sun,Mengdi Xu,Mingming Zhang,Chuanzhuang Zhao
Poly(methylacrylamide) (PMAM) is a thermo-responsive polymer with an upper critical solution temperature (UCST). Its cloud point ( T cp ) is around 60 °C, unsuitable for certain biomedical and industrial applications. This study brought up a copolymerization strategy to tune the T cp of PMAM with hydrophilic comonomers. Surprisingly, with a small portion of hydrophilic monomer doped, the T cp of the PMAM copolymer can be significantly shifted. For instances, with ≤7 mol% of acrylamide or 1 mol% of oligo(ethylene glycol) methacrylate, the T cp can be shifted in a wide range from ~69 to ~0 °C. Microdifferential scanning calorimetry demonstrated that the enthalpic effect during the phase transition of the solutions is indistinctive, while fluorescence measurement with pyrene as a probe revealed that the hydrogen-bonding within polymer chains is enhanced by the hydrophobic aggregation of methyl groups. Therefore, the doped hydrophilic monomer could remarkably alter the ordering of water-molecules and the extent for the aggregation of methyl groups, leading to the pronounced shifting in the T cp of the copolymers. This work would facilitate the application of PMAM as smart polymer materials and guide the inventions of functional materials based on UCST polymers. Graphical
研究领域:
材料科学
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高分子化学
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生物医学工程
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DOI
JOURNAL OF POWER SOURCES
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2017
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IF 6.395
Jinchao Li,Suqin Liu,Zhen He,Zhi Zhou
A novel branched side-chain-type sulfonated polyimide (6F-s-bSPI) membrane with accessible branching agents of melamine , hydrophobic trifluoromethyl groups ( CF 3 ), and flexible sulfoalkyl pendants is prepared by a high-temperature polycondensation and post-sulfonation method for use in vanadium redox flow batteries (VRFBs). The chemical structure of the 6F-s-bSPI membrane is confirmed by ATR-FTIR and 1 H NMR spectra. The physico-chemical properties of the as-prepared 6F-s-bSPI membrane are systematically investigated and found to be strongly related to the specially designed structure. The 6F-s-bSPI membrane offers a reduced cost and possesses a significantly lowered vanadium ion permeability (1.18 × 10 −7 cm 2 min −1 ) compared to the linear SPI (2.25 × 10 −7 cm 2 min −1 ) and commercial Nafion 115 (1.36 × 10 −6 cm 2 min −1 ) membranes, prolonging the self-discharge duration of the VRFBs. In addition, the VRFB assembled with a 6F-s-bSPI membrane shows higher coulombic (98.3%–99.7%) and energy efficiencies (88.4%–66.12%) than that with a SPI or Nafion 115 membrane under current densities ranging from 20 to 100 mA cm −2 . Moreover, the VRFB with a 6F-s-bSPI membrane delivers a stable cycling performance over 100 cycles with no decline in coulombic and energy efficiencies. These results show that the branched side-chain-type structure is a promising design to prepare excellent proton conductive membranes.
研究领域:
材料科学
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电化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Xizi Wu,Zhixiang Zhai,Jia Wu,Kexin Tan,Zhili Li,Shibin Yin
5-Hydroxymethylfurfural electrooxidation reaction (HMFOR) has attracted increasing attention due to energy conservation and value-added production. It is crucial to design highly active catalysts with fast kinetics and reveal the catalytic mechanism. Herein, the activation of hydroxymethyl/aldehyde groups is tuned on V 2 O 3 -modificated CuCo for efficient HMFOR. Experimental and theoretical results reveal that strong electron transfer occurs on the heterointerface between V 2 O 3 and CuCo, endowing its unique electronic structure and conductivity. Meanwhile, CuCo-V 2 O 3 heterostructure facilitates the modulation of local electron density, charge transfer, and adsorption behavior to promote the activation of hydroxymethyl/aldehyde groups. The higher activation of hydroxymethyl groups than that of aldehyde groups over CuCo-V 2 O 3 induces an altered rate-determining step for HMFOR. Consequently, CuCo-V 2 O 3 presents enhanced HMFOR activity (E 10 , 1.27 V RHE ), reaction kinetics (38 mV dec −1 ), 2,5-furandicarboxylic acid selectivity (99.1%), and stability (40 successive cycles). This work provides a strategy for designing highly active catalysts for synthesizing value-added products.
研究领域:
电化学
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催化
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材料科学
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能源转化
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DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-10
·
IF 16.6
Zhang Wenqing,Xi Dawei,Chen Yihong,Chen Aobo,Jiang Yawen,Liu Hengjie,Zhou Zeyu,Zhang Hui,Liu Zhi,Long Ran,Xiong Yujie
Oxidative carbonylation of methane is an appealing approach to the synthesis of acetic acid but is limited by the demand for additional reagents. Here, we report a direct synthesis of CH 3 COOH solely from CH 4 via photochemical conversion without additional reagents. This is made possible through the construction of the PdO/Pd–WO 3 heterointerface nanocomposite containing active sites for CH 4 activation and C–C coupling. In situ characterizations reveal that CH 4 is dissociated into methyl groups on Pd sites while oxygen from PdO is the responsible for carbonyl formation. The cascade reaction between the methyl and carbonyl groups generates an acetyl precursor which is subsequently converted to CH 3 COOH. Remarkably, a production rate of 1.5 mmol g Pd –1 h –1 and selectivity of 91.6% toward CH 3 COOH is achieved in a photochemical flow reactor. This work provides insights into intermediate control via material design, and opens an avenue to conversion of CH 4 to oxygenates.
研究领域:
化学工程
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光化学
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材料科学
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催化
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产品关联
DOI
PubMed
高影响因子
Current Protocols
·
2024
·Vol. 4
·期 1
·e956
·
IF 0
Xuan Chen,Long Xie,Chenglong Zhang,Shen Tian,Zeyu Tang,Ming Xiang,Weiwei Tian,Patrick Lu,Xianbin Yang
The integration of fluorine atoms into biologically active organic compounds has proved to be a vital technique in small molecule drugs. This technique can substantially enhance crucial properties, including metabolic stability, lipophilicity, and bioavailability, often with a mere addition of a single fluorine atom or a trifluoromethyl group. Over the past few decades, this concept has also been applied in nucleic acid chemistry. A commonly employed 2′-OH substitution is the introduction of a 2′-deoxy-2′-fluoro (2′-F) group. The strong electronegativity of fluorine prompts the modified siRNA to readily adopt a C3′- endo conformation, resulting in significant advantages in terms of binding affinity. To enrich the toolbox of chemical modification of oligonucleotides, the replacement of the 2′-OH with the 2′- O -trifluoromethyl group has been developed in RNA analog synthesis. Oligodeoxynucleotides containing the 2′- O -trifluoromethyl group can greatly increase the thermal stability of DNA/RNA duplexes depending on the position and amount of the modification. Moreover, 2′- O -trifluoromethylated oligodeoxynucleotide also exhibited a slightly higher resistance to snake venom phosphodiesterase than the unmodified oligodeoxynucleotide. The 2′- O -trifluoromethylated oligonucleotides can emerge as a label to study RNA structure and function as well, or to develop DNA/RNA-based diagnostics. Hence, it is necessary to report an effective method for the synthesis, deprotection, purification, and characterization of oligonucleotides bearing a 2′ -O -trifluoromethyl group. © 2024 Wiley Periodicals LLC. Basic Protocol 1 : Preparation of 6- N -benzoyl-5′- O -dimethoxytrityl-2′- O -trifluoromethyl adenosine 3′-(2-cyanoethyl N,N -diisopropyl)phosphoramidite Basic Protocol 2 : Preparation of 4- N -acetyl-5′- O -dimethoxytrityl-2′- O -trifluoromethyl cytidine 3′-(2-cyanoethyl N,N -diisopropyl)phosphoramidite Basic Protocol 3 : Preparation of 2- N -isobutyryl-5′- O -dimethoxytrityl-2′- O -trifluoromethyl guanine 3′-(2-cyanoethyl N,N -diisopropyl)phosphoramidite Basic Protocol 4 : Preparation of 5′- O -dimethoxytrityl-2′- O -2-trifluoromethyl uridine 3′-(2-cyanoethyl N,N -diisopropyl) phosphoramidite Basic Protocol 5 : Solid-phase synthesis of 2′- O -trifluoromethylated RNA analogs Basic Protocol 6 : Deprotection and purification of 2′- O -trifluoromethyl-RNAs
研究领域:
生物有机化学
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核酸化学
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药物化学
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RNA生物学
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分子生物学
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药学
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DOI
危险品化学品经营许可证（带存储）