CHINESE JOURNAL OF CHEMISTRY
·
2011
·Vol. 29
·期 9
·1906-1910
·
IF 0.773
Lin Yan,Wenguo Yang,Lixin Li,Yang Shen,Zhiyong Jiang
A mild and facile Wittig reaction between N -substituted maleimides and aldehydes has been developed. Various synthetically valuable alkylidenesuccinimides were obtained from this one-pot reaction in high yields (up to 99%). The product was obtained by simple filtration and no extra purification was necessary. Ethanol, an environment-benign solvent, was found to be a suitable reaction medium.
研究领域:
有机化学
·
药物化学
·
绿色化学
·
合成方法学
·
medicinal chemistry
✓ 已验证
DOI
高影响因子
TRIBOLOGY LETTERS
·
2019
·Vol. 67
·期 1
·1-17
·
IF 2.235
Zhao Yuanliang,Qi Xiaowen,Zhang Wenli,Fan Bingli,Yang Qingxiang
The effects of copper nanoparticles (Cu) located in different regions of polytetrafluoroethylene/polyimide (PTFE/PI) blends on the morphology, thermal, mechanical, and tribological properties of PTFE composites were studied. Region one is PI phases (the corresponding composites is denoted as PPC), region two is PTFE phases and the interface between PTFE and PI (the corresponding composites is denoted as PPC-m). Results indicate that the incorporation of Cu nanoparticles into PI phases improves the dispersibility and homogeneity of PI phases. As a consequence, the crystallinity of PTFE composites is reduced, but compressive strength and modulus of PTFE composites are enhanced by 50.3% and 14.4% respectively. In addition, self-lubricity and wear resistance of PTFE composites are improved by 10.4% and 50.5%. Scanning electron microscopy (SEM) demonstrates that PI phases with Cu nanoparticles hinder the direct contact between PTFE matrix and counterparts. However, Cu nanoparticles located in PTFE matrix and the interface between PTFE and PI deteriorates the dispersibility and homogeneity of PI phases, which lead to the poor mechanical and tribological performance of PTFE composites.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2016
·
IF 5.557
Sikuai Xue,Chengcai Li,Jiuming Li,Hailin Zhu,Yuhai Guo
To improve hydrophilicity and anti-fouling property of the polytetrafluoroethylene (PTFE) flat microfiltration (MF) membrane, a facile method was developed to modify the membrane via the co-deposition of catechol (CA) and polyethyleneimine (PEI) followed by surface mineralization of γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560). The surface chemical composition, surface morphology, hydrophilicity and filtration performance of the PTFE flat membrane were investigated by ATR-FTIR, XPS, FESEM, WCA and pure water flux measurements, respectively. After using this low-cost and simple modification method, the PTFE flat membrane was endowed with excellent hydrophilicity, high water permeation flux and superior anti-fouling property. Then, the oil/water separation tests were conducted using the modified PTFE flat membranes. The size distribution of the oil droplets is between 0.12–1.44 µm and the mean pore size of pristine PTFE flat MF membrane is 0.22 µm. The as-prepared hydrophilized PTFE flat membranes possess an excellent oil resistant ability with oil rejection ratio near 99%. Finally, the surface stability of the modified membrane was studied and the mineralized membrane showed excellent acid resistant ability. Therefore, this facile strategy holds attractive potential practical application in water environmental remediation.
研究领域:
材料科学
·
环境工程
·
膜技术
·
表面化学
·
水处理
✓ 已验证
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 306
·期 11
·2100456
·
IF 4.367
Zhiqiang Wu,Qiang Guo,Yang Liu,Huihui Zhou,Hua Zheng,Xingfeng Lei,Lei Gong,Yanhui Chen,Zhenguo Liu,Qiuyu Zhang
In order to meet the requirements of polymer dielectric materials for high thermal stability and excellent dielectric properties in the application of high-temperature film capacitors, a series of polyimide (PI) films are fabricated by introducing a self-synthesized aniline trimer (ACAT) with a conjugated structure in this work. Since the conjugated ACAT in the main chains of PI improves the electron polarization and carrier mobility of the PI molecular chains, the dielectric constant of the ACAT-PI films is greatly enhanced (4.4–7.4). Meanwhile, the dissipation factor does not increase apparently (0.002–0.013). The dielectric properties are stable even when the temperature is up to 200 °C, the thermal degradation temperature is as high as 450 °C, and the mechanical properties are also excellent (70–105 MPa). Among all the films, the PI film with 5 mol% ACAT exhibits the maximal energy density of 3.6 J cm −3 under the field of 426 kV mm −1 , the high tensile strength (90 MPa) and the excellent thermal stability ( T d5 = 515 °C). The work paves the way to prepare high-temperature polymer dielectric film materials with high energy storage density.
研究领域:
材料科学
·
高分子化学
·
介电物理
·
能源材料
·
功能高分子
✓ 已验证
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2017
·Vol. 38
·期 4
·1600551
·
IF 4.265
Shi-Lei Dong,Lu Han,Cai-Xia Du,Xiao-Yu Wang,Lu-Hai Li,Yen Wei
Electroactive hydrogel scaffolds are fabricated by the 3D-printing technique using composites of 30% Pluronic F127 and aniline tetramer-grafted-polyethylenimine (AT-PEI) copolymers with various contents from 2.5% to 10%. The synthesized AT-PEI copolymers can self-assemble into nanoparticles with the diameter of ≈50 nm and display excellent electroactivity due to AT conjugation. The copolymers are then homogeneously distributed into 30% Pluronic F127 solution by virtue of the thermosensitivity of F127, denoted as F/AT-PEI composites. Macroscopic photographs of latticed scaffolds elucidate their excellent printability of F/AT-PEI hydrogels for the 3D-printing technique. The conductivities of the printed F/AT-PEI scaffolds are all higher than 2.0 × 10 −3 S cm −1 , which are significantly improved compared with that of F127 scaffold with only 0.94 × 10 −3 S cm −1 . Thus, the F/AT-PEI scaffolds can be considered as candidates for application in electrical stimulation of tissue regeneration such as repair of muscle and cardiac nerve tissue.
研究领域:
生物材料
·
组织工程
·
再生医学
·
高分子化学
·
生物医学工程
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2016
·Vol. 217
·期 24
·2726-2735
·
IF 2.495
Huiliang Sun,Shuren Zhang,Yike Yang,Xiao Li,Hongmei Zhan,Yanxiang Cheng
Six aryl Pd(II) bromide complexes based on perylene diimide derivative (Ar) and phosphine mixed-ligands are successfully synthesized by directly oxidative addition of Ar–Br to the Pd(0) precursor. These complexes with the general formulas ArPdBr(PCy 3 ) 2 (PCy 3 = tricyclohexylphosphine; Pd1–Pd3 ) and [ArPdBr(TXP-2,4)] 2 (TXP-2,4 = tri-2,4-xylylphosphine; Pd4–Pd6 ) are stable and can be handled in air at room temperature. By employing the Pd(II) complexes as initiators, Suzuki catalyst transfer polymerization (SCTP) of AB-type fluorene monomer is investigated for preparing polyfluorenes (PFs) with the defined end group. Complexes Pd4–Pd6 with auxiliary TXP-2,4 ligand can initiate polymerization of AB-type fluorene monomer at room temperature, while higher polymerization temperature is required for Pd1–Pd3 with alkyl phosphine PCy 3 . The obtained polymers are analyzed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, which confirms that the Ar group is appended to the terminus of the polymer chain. Moreover, PFs prepared by Pd4–Pd6 -catalyzed SCTP bear precisely the Ar group on one chain end and 4- tert -butylphenyl end-capping group on the opposite end, which indicates that Pd4–Pd6 with the bulky TXP-2,4 exhibit better catalytic performance in SCTP. Photoluminescence spectra of the obtained polymers show a dual or a blue emission resulting from the difference of the molecular weight.
研究领域:
高分子化学
·
有机合成
·
功能材料
·
聚合反应机理
·
光电子材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 135
·期 13
·46036
·
IF 1.86
Yanfang Hu,Weiqian Ma,Meilin Tao,Xueyan Zhang,Xiaohong Wang,Xiaoyu Wang,Li Chen
Herein, we present a strategy for supporting bromine as a catalyst for the oxidation of sulfides. In this strategy, branched poly(ethylene imine) was first decorated by magnetic oxide and then used to support liquid bromine to obtain solid polymeric bromine (M@PEI@Br) nanoparticles. Compared with free bromine, the stability of the M@PEI@Br nanoparticles improved obviously. The oxidation of thioanisole to methyl phenyl sulfoxide was chosen as a reaction model to evaluate the catalytic activity of the M@PEI@Br nanoparticles. All of the obtained results verify that the M@PEI@Br nanoparticles exhibited excellent catalytic efficiency and could accelerate the oxidation process under solvent-free conditions at room temperature; this highlighted the potential of decorated polymers to support active and unstable small-molecule organic catalysts. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46036.
研究领域:
催化化学
·
高分子材料
·
纳米科技
·
有机合成
·
绿色化学
✓ 已验证
DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
·
2017
·
IF 3.756
Yu Huang,Jin-Mei Li,Zhi-Hui Lai,Jun Wu,Tong-Bu Lu,Jia-Mei Chen
Both cocrystal and nanocrystal technologies have been widely used in the pharmaceutical development for poorly soluble drugs. However, the synergistic effects due to the integration of these two technologies have not been well investigated. The aim of this study is to develop a nano-sized cocrystal of phenazopyridine (PAP) with phthalimide (PI) to enhance the release rate and oral bioavailability of PAP. A PAP–PI nano-cocrystal with particle diameter of 21.4 ± 0.1 nm was successfully prepared via a sonochemical approach and characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamic light scattering (DLS) analysis. An in vitro release study revealed a significant release rate enhancement for PAP–PI nano-cocrystal as compared to PAP–PI cocrystal and PAP hydrochloride salt. Further, a comparative oral bioavailability study in rats indicated significant improvement in C max and oral bioavailability (AUC 0 − ∞ ) by 1.39- and 2.44-fold, respectively. This study demonstrated that this novel nano-cocrystal technology can be a new promising option to improve release rate and absorption of poorly soluble compounds in the pharmaceutical industry.
研究领域:
药剂学
·
药物递送
·
纳米医学
·
药物代谢
·
晶体工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2022
·
IF 10.319
Wenqiang Hu,Wenbin Fu,Samik Jhulki,Liang Chen,Aashray Narla,Zhijian Sun,Fujia Wang,Alexandre Magasinski,Gleb Yushin
Poor heat/flame-resistance of polyolefin (e.g., polyethylene and polypropylene) separators and high flammability of organic electrolytes used in today's lithium-ion batteries (LIBs) may trigger rare yet potentially catastrophic safety issues. Here, we mitigate this challenge by developing a heat-resistant and flame-retardant porous composite membrane composed of polyetherimide (PEI) and Al 2 O 3 nanowires (NWs). The membranes are fabricated based on an industrially scalable non-solvent-induced phase separation process, which results in an intimately interconnected porous network of Al 2 O 3 NWs and PEI . The produced composite membranes exhibit excellent flexibility, thermal stability, and flame-retardancy. Importantly, the composite membranes exhibit minimal thermal shrinkage and superior tensile strength (16 MPa) at temperatures as high as 200 °C, significantly exceeding the performance of conventional polyolefin separators. Compared with commercial separators, their superior wettability and higher ionic conductivity (by up to 2.4 times) when filled with the same electrolyte, larger electrolyte uptake (∼190 wt.%), as well as improved cycle and rate performance demonstrated in LiNiMnCoO 2 (NCM)-based LIBs make them attractive choices for a variety of electrochemical energy storage devices.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子科学
·
纳米技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Naseem Akhtar,Hongyuan Shao,Fei Ai,Yuepeng Guan,Qifan Peng,Hao Zhang,Weikun Wang,Anbang Wang,Bingyin Jiang,Yaqin Huang
Lithium-sulfur (Li-S) batteries with high specific capacity are expected to be a new generation of energy storage devices. However, the shuttle effect of lithium polysulfide makes it difficult to commercialize stable Li-S batteries. In this work, we designed a gelatin-polyethylenimine composite (GPC) as functional binder for Li-S batteries to improve the stability of electrode during discharge-charge process. GPC binder combines the dispersion and adhesion ability of gelatin, which keeps cathode homogeneous and stable during electrochemical reaction , and adsorption capability of PEI for polysulfide , which suppresses the “shuttling effect”. The result shows that GPC used as a binder remarkably enhanced cyclic performance of Li-S battery with good capacity retention of about 100% at current density of 1C (sulfur loading 1.5 mg cm −2 ) after 100 cycles. We believe that GPC would be a promising binder for highly stable Li-S batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子化学
·
纳米复合材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Kuirong Deng,Suping Zhou,Zelin Xu,Min Xiao,Yuezhong Meng
High-performance polymer electrolytes with the capability to self-heal mechanical damage can effectively enhance reliability, safety and service life of the batteries. Herein, a novel polymer electrolyte (PBPE) with excellent self-healing capacity and high ionic conductivity was developed. PBPE with polymer networks cross-linked by highly reversible imine bonds was fabricated by the Schiff-base reaction between poly(ethylene glycol) diamine and benzene-1,3,5-tricarbaldehyde. PBPE can quickly repair the cut damage spontaneously within 1 h at room temperature and recover its mechanical strength and electrochemical properties. The healed PBPE exhibits almost the same ionic conductivities and mechanical properties as the original PBPE shows. PBPE possesses the highest ionic conductivity (4.79 × 10 −3 S cm −1 at 30 °C) among the self-healing polymer electrolytes. PBPE can promote the generation of LiF-rich SEI and effectively suppress dendrite growth on Li metal anodes. LiFePO 4 (LFP) cells assembled with PBPE exhibit excellent rate capability (discharge capacity of 118.2 mAh g −1 at 5 C rate) and good cycling performance (capacity retention of 97.8% over 125 cycles). More importantly, the healed PBPE can completely recover its properties from damage in LFP cells and enable the cells to possess cycle performance identical to original PBPE.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子化学
·
电池技术
✓ 已验证
DOI
高影响因子
CARBON
·
2012
·Vol. 50
·期 8
·2810-2815
·
IF 5.378
Yongqiang Dong,Ruixue Wang,Hao Li,Jingwei Shao,Yuwu Chi,Xiaomei Lin,Guonan Chen
Polyamine-functionalized carbon quantum dots (CQDs) with high fluorescence quantum yield (42.5%) have been synthesized by the low temperature (<200 °C) carbonization of citric acid with branched polyethylenimine (BPEI) in one simple step. The obtained BPEI–CQDs are spherical graphite nanocrystals (average 6.2 nm in size) capped with abundant BPEI at their surfaces. It is the first report that CQDs are both amino-functionalized and highly fluorescent, which suggests their promising applications in chemical sensing.
研究领域:
分析化学
·
纳米材料
·
生物传感
·
荧光成像
·
分子探针
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）