SYNTHETIC METALS
·
2015
·
IF 2.252
Yin Yu,Bo Jin,Rufang Peng,Lisheng Fan,Longhua Cai,Bin Fan,Shijin Chu
A series of [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) analogs with different ester structures, such as isopropyl ester (F 1 ), sec-butyl ester (F 2 ), ethyl ester (F 3 ), 2-thiopheneethyl ester (F 4 ), phenethyl ester (F 5 ), and 4-methoxyphenethyl ester (F 6 ), were designed, synthesized, and evaluated for their photovoltaic performance. The optical, electrochemical, morphological, and photovoltaic properties of the molecules were characterized through UV–vis spectroscopy, cyclic voltammetry, and atomic force microscopy; then, the effects of different ester structures on these properties were investigated. Results showed that polymer solar cells (PSCs) with P3HT as a donor and F 1 –F 6 as acceptors displayed different photovoltaic properties. The PSCs with F 1 , F 2 , and F 3 as acceptors showed higher photovoltaic performance than those with F 4 , F 5 and F 6 as acceptors. Moreover, the power conversion efficiency of the former three PSCs exceeded or approached 3.0%, whereas that of the latter three PSCs was below 2.0%. Compared with PCBM, F 2 and F 3 with an aliphatic ester exhibited a slightly better photovoltaic performance, F 1 with isopropyl ester displayed similar photovoltaic properties, and other aromatic ring ester PCBM-like derivatives showed poorer photovoltaic performance.
研究领域:
材料科学
·
光电化学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2019
·
IF 4.046
Baoguo Ma,Chunbao Li,Yang Lv,Hongbo Tan,Hui Wang,Huahui Qi,Xiaohai Liu,Qi Yang,Pian Chen
The problem of bleeding and segregation in high fluidity concrete can be eliminated by the addition of viscosity-enhancing agents (VEA). However, the dispersion capacity of PCE would be perturbed by the addition of VEA. In most cases, this negative impact was due to competitive adsorption between VEA and PCE. In order to mitigate the negative impact, ester groups were introduced to reduce the adsorption capacity, and one new kind of viscosity-enhancing agents was designed; the polymers were copolymerized of acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA), with 1:1 and 1:8 M ratios of AA and HEA. And then, the effect of these two VEAs on rheology of cement paste plasticized by PCE at 5 min and 30 min were studied. Adsorption behavior was analyzed by total organic carbon (TOC), and the zeta potential was also measured. The conformation of the polymers in liquid phase were analyzed by dynamic light scattering (DLS). And the decomposition of ester group under alkaline condition was verified by FTIR and 1 HNMR. The results indicated that the synthesized VEA could plasticize cement paste, and the reason was that VEA could be adsorbed by cement grains and act as the same role as the first-generation superplasticizer. The plasticizing capacity was increased over time, because the adsorption capacity was enhanced due to the released carboxyl groups from the decomposition of ester groups. Furthermore, from 5 min to 30 min, the decomposition of ester group could increase the conformation size of VEA by producing crosslinking in the presence of Ca 2+ , and the crosslinking act as positive role in increasing viscosity and resist the bleeding and segregation. Moreover, it was observed that VEA had negative impact on dispersion capacity of PCE, and the higher density of ester group resulted in lower negative impact at the beginning; one reason for this was because the higher density of ester group showed lower competitive adsorption capacity. Such results offered one new type of VEA available for superplasticizer system.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 135
·期 10
·45940
·
IF 1.86
Mei Wang,Jianchun Jiang,Jianling Xia,Shouhai Li,Mei Li
Phosphate ester groups containing ricinoleic acid-based Ca/Zn (LPPRA-Ca and LPPRA-Zn) stabilizer was successfully synthesized from ricinoleic acid (RA) and used as thermal stabilizers for poly(vinyl chloride) (PVC). These thermal stabilizers were characterized by Fourier transform infrared spectrometry, 1 H nuclear magnetic resonance, and inductively-coupled plasma atomic emission spectroscopy. The effects of LPPRA-Ca/LPPRA-Zn, CaSt 2 /ZnSt 2 , and other stabilizers on the thermal stability of PVC were studied through Congo Red test, discoloration tests, thermogravimetric analysis (TGA), TGA–infrared, and TGA–mass spectrometry. The thermal stability tests show that LPPRA-Ca/LPPRA-Zn displays the best initial color stability and long-term thermal stability for PVC. The superior performance is attributed to the synergistic effect of LPPRA-Ca and LPPRA-Zn. Moreover, a lower Zinc content of LPPRA-Zn in PVC helps to decrease the “zipper dehydrochlorination” of the product, which contributes to a better initial thermal stability. Except for the better stabilization performance, LPPRA-Ca/LPPRA-Zn also displays better plasticization performance for PVC compared with other stabilizers. A possible stabilizing mechanism of PVC/LPPRA-Ca/LPPRA-Zn system was presented. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 45940.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2014
·
IF 1.09
Yongpeng Wang,Haibo Zhang,Mengzhu Liu,Yingshuang Shang,Yingjian Lin,Zhenhua Jiang
A novel poly(arylene ether sulfone) (PAES) with pinacol phenylboronate pendants (PAES-B) was prepared by the borylation of brominated PAES (PAES-Br). The reaction was carried out under mild conditions in the presence of cuprous iodide and tri-n-butylphosphine in tetrahydrofuran solution. After heat treatment at 150°C for 132 h, the PAES-B exhibited an interesting solvent resistance. Fourier transform infrared spectroscopy (FTIR) and thermal analysis were performed to investigate the reason. FTIR spectra showed that heat treatment could facilitate losing of pinacol groups and formation of phenylboronic acid in the polymer. Meanwhile, differential scanning calorimetric (DSC) curves demonstrated that the polymer had cross-linking behaviors during heat treatment. In addition, the thermal oxidative stability of PAES-B was researched by the thermogravimetric analysis (TGA).
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2014
·Vol. 14
·期 7
·4837-4842
·
IF 1.339
Liu Hanxia,Song Zhijian,Chen Xuemei
A photocleavable nitrobenzyl ester group was introduced in the backbone of self-assembling peptides using standard Fmoc-peptide systhesis. The nitrobenzyl ester group could be used as a cleavable linker to connect a gelator and a hydrophilic group. Photo-irradiation would lead to the
generation of the molecular gelator and the formation of a molecular hydrogel. The nitrobenzyl ester group could also be used as one part of hydrophobic capping group for short peptides to produce molecular hydrogelators. In this case, photo-irradiation would lead to the release of hydrophobic
anti-imflammatory drug of Naproxen and the gel-sol phase transition. The application of photocleavable group in molecular self-assembly would lead to photo-controllable self-assembly materials for controlled drug release, tissue engineering, and regenerative medicine.
研究领域:
生物材料学
·
药物递送
·
组织工程学
✓ 已验证
DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 4
Zhang Xiao-Hui,Zhao Ya-Jun,Wang Can,Tang Shan
Incorporating a low density of ester units into the backbone of polyethylene materials enhances their sustainability and recyclability while maintaining the main material properties of polyethylenes. Here we report a new way to access degradable polyethylene materials with a low content of in-chain ester units via mechanochemical backbone editing. Initially, ester groups are incorporated as side groups through catalytic copolymerization of ethylene with a cyclobutene-fused lactone monomer (CBL), yielding polyethylene materials with high molecular weights and adjustable thermomechanical properties. Subsequent solid-state ball-milling treatment selectively introduces side-chain ester groups into the main chain of the polyethylene materials via force-induced cycloreversion of the cyclobutane units. Under acidic conditions, hydrolysis of the resultant polyethylene materials with in-chain ester units facilitates further degradation into oligomers.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Lubricants
·
2024
·Vol. 12
·期 12
·455
·
IF 3.1
Linghao Zhang,Qiuyu Shi,Xiangyu Ge
Electro-regulated friction is a widely adopted approach for reducing friction, with graphene oxide (GO) emerging as a promising lubricating additive due to its electro-responsive frictional behaviour. However, with the wide variety of functionalized GO additives available, each exhibiting distinct properties, it remains unclear which type demonstrates the most effective electro-regulated friction-reducing performance, limiting their broader industrial application. In this study, the frictional behaviour of three functionalized GO additives under electric stimulation was investigated along with an analysis of the corresponding worn surfaces. The findings reveal the role of functional groups in determining the tribological performance of functionalized GO additives and the mechanism of electric stimulation. Notably, the formation of ester groups during the friction process of GO-OH enhances the adsorption of GO additives onto steel surfaces, resulting in superior friction-reducing properties. Under lubrication with GO-OH additives, negative electric stimulation promotes the generation of ester groups and transitions the lubrication regime to mixed lubrication, thereby contributing to friction reduction. This work provides new insights into the tribological performance of functionalized GO additives and the mechanisms underlying their electro-regulated behaviours, laying a foundation for the design of GO additives with superior lubrication performance for practical engineering applications.
研究领域:
材料科学
·
机械工程
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2014
·
IF 3.96
Ling-Ling Shao,Quan-Fu An,Yan-Li Ji,Qiang Zhao,Xue-San Wang,Bao-Ku Zhu,Cong-Jie Gao
Sulfated carboxymethyl cellulose (SCMC) with tailored amount of sulfate groups was synthesized, and their composite nanofiltration membranes (SNFMs) were prepared by solution casting onto polysulfone (PSF) supporting membrane and crosslinking by glutaradehyde (GA). Chemical structure and composition of SCMCs and SNFMs were characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. SNFM surfaces were examined by field emission scanning electron microscopy , water contact angle and streaming potential measurement. The effects of the chemical composition on the hydrophilicity , the surface charge and the nanofiltration performance of SNFMs were determined. It is found that the incorporation of sulfate groups improves the water permeability of SNFMs while retaining their salt rejection. For the feed mixture of aqueous Na 2 SO 4 (1.0 g L − 1 , pH = 6.5), the optimum water flux is 39.6 L m − 2 h − 1 , which is 2.2 times of the pristine SNFM-0. For the xylenol orange (XO) dye solution (0.1 g L − 1 , pH = 4.0), the flux of SNFM-3 (30.0 L m − 2 h − 1 ) is also higher than that of SNFM-0 (11.1 L m − 2 h − 1 ). In addition, SNFM-3 exhibits good separation performance and chemical stability in treating saline anionic dye aqueous solution (MYB/NaCl) in acidic conditions.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Yehan Yang,Mengxia Xu,Zhu Luo,Ruhui He,Jikai Xie,Shenglong Yang,Hu Chen,Huaibin Li
To address the compatibility challenges between polypropylene (PP) and poly(ethylene terephthalate) (PET), a long-chain-branched polypropylene compatibilizer featuring ester groups (LCB-PP-E) was synthesized from PP and pentaerythritol triacrylate (PETA), facilitated by the initiator dicumyl peroxide. The structure of LCB-PP-E was characterized by using infrared spectroscopy, rheology, and melt flow index analysis, while potential reaction mechanisms were discussed. The morphology of the blend was examined by scanning electron microscopy and Raman spectroscopy. The effects of LCB-PP-E on the thermodynamic and crystallization behavior of PP/PET blends were studied by dynamic mechanical analysis, differential scanning calorimetry, and polarizing microscopy. LCB-PP-E sampled at the reaction peak point exhibited a longer branched PP chain compared to that of LCB-PP-E obtained at the balance torque, facilitating better entanglement with PP macromolecules. Furthermore, the ester groups on LCB-PP-E engaged in transesterification reactions with the ester groups on the PET chains. The combined effects of these interactions effectively reduced the interfacial tension between the two phases, resulting in a decreased size of the dispersed PET phase and a more uniform distribution. Additionally, the introduction of LCB-PP-E significantly narrowed the crystallization and glass transition temperature difference between the phases. The enhanced compatibility led to an increase in elongation at break, demonstrating a transition of the blend from a brittle material to a ductile material. This compatibilization system shows substantial potential for high-quality applications in PP/PET recycled plastics.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Jiashuai Yao,Xueying Liu,Haibin Sun,Suting Liu,Yingjie Jiang,Bing Yu,Nanying Ning,Ming Tian,Liqun Zhang
In this study, ester group grafted polymethylvinylsiloxane (PMVS-COCH3) with low elastic modulus (Y) and strong polarizability was synthesized and introduced into thermoplastic polyurethane (TPU) with good mechanical properties, high dielectric constant (εr), and easy recyclability to prepare high performance dielectric elastomer (DE). PMVS-COCH3 with high grafting degree and low molecular weight was synthesized via the thiol–ene addition reaction and then was solution blended with TPU at low PMVS-COCH3/TPU blending ratios. The as-prepared blends still exhibit good mechanical properties and relatively high electrical breakdown strength because the low content of insulated PMVS-COCH3 phase is dispersed in continuous TPU phase. Both simulation and experimental results indicate that the ester groups on PMVS-COCH3 can form hydrogen bonds with TPU, leading to the disruption of C═O/N–H hydrogen bonding between TPU chains and thus enhancing dipole polarizability. Meanwhile, the PMVS-COCH3 dispersed phase acts as a soft polar filler in the TPU matrix, resulting in interfacial polarization and lower Y. Both the introduction of interfacial polarizability and the improvement of dipole polarizability largely increase the εr of the blend. The actuated strain under the same electric field of the blends over that of pristine TPU is largely improved. At the blending ratio of 3/7, the actuated strain reaches 6.9% without any prestrains, which is the highest actuated strain among various previously reported TPU-based DEs.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Bo Pang,Qi Zhang,Xiaoming Yan,Xiaozhou Wang,Wanting Chen,Ruohan Du,Xuemei Wu,Minggang Guo,Gaohong He,Fujun Cui
Proton conductive group is essential to provide ion transport site and tune micro-phase separation in proton exchange membranes for vanadium redox flow battery (VRFB), while nearly all the fabrication methods are based on the benchmark sulfonic acid group. Herein, the sulfate ester group (-OSO 3 H) with superior acidity is proposed as a novel proton conductive group to achieve high proton transport at lower IECs, therefore disentangles the trade-off between vanadium crossover and conductive ion diffusion. The electron withdrawing ester oxygen atom endows sulfate ester group with 27 kJ mol −1 lower proton binding energy than the sulfonic acid group, leading to higher proton dissociation ability and better micro-phase separation. The 1,3-propanediol cyclosulfate grafted polybenzimidazole with IEC of 1.85 (OPBI-OSO 3 H-1.85) reaches comparable area resistance (0.19 Ω cm −2 ) to the sulfonic acid grafted polybenzimidazole with much higher IEC of 2.95 (OPBI-SO 3 H-2.95), but 19.1% decrease in vanadium permeability. The cell assembled with OPBI-OSO 3 H-1.85 achieves high energy efficiency of about 86.7% and low decay of discharge capacity (0.41% per cycle), superior to that of OPBI-SO 3 H-2.95 (0.51% per cycle) and Nafion 212 (0.71% per cycle). The sulfate ester group is proved to be chemically stable in H 2 SO 4 /vanadium environment.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2024
·
IF 2.4
Zhang Jingchun,Wang Qiqi,Chen Haoyuan,Zhang Yilin,Deng Yupei,Wang Ying,Zhao Huimin,Zhu Yu,Wang Guowei,Zhuang Linghua
It is found that ester introduction into imidazolium or pyridinium cations can significantly improve the biodegradability property of ionic liquids and also influence the viscosity and the toxicity of ionic liquids. Ionic liquids based on dicyanamide anion reveal good electrochemical properties. Four chloride and dicyanamide ionic liquids with ester groups were prepared, and the effect of anion and cation structure of ionic liquids on electrical conductivity/electrochemical stability window was discussed from experimental studies and density functional theory (DFT) simulations. The introduction of the ester group in imidazolium cation decreased the refractive index and electrical conductivity, while increasing the electrochemical stability window of ionic liquids. The refractive index, electrical conductivity, and electrochemical stability window values decreased with the increase of the alkyl chain length of the ester group from ethyl to butyl. The refractive index values of chloride imidazolium ionic liquids were higher than those of dicyanamide ionic liquids, while the electrical conductivity and electrochemical stability window values of dicyanamide ionic liquids were much higher than those of chloride ionic liquids. DFT simulations revealed that ester introduction in imidazolium cation decreased the average hydrogen bond length and increased the cation–anion interaction. The average hydrogen bond length of chloride and dicyanamide ionic liquids increased with the increase of the alkyl chain length of the ester group from ethyl to butyl, while the absolute interaction energy (Δ E ) of chlorine and dicyanamide ionic liquids decreased with the increase of the alkyl chain length of the ester group from ethyl to butyl. DFT simulations demonstrated that ionic liquid structure (ester chain length and anion) was closely related to the electrical conductivity and electrochemical stability window properties of ionic liquids. These results will shed light on the design and optimization of functional ionic liquids as electrolytes for renewable energy and energy storage applications.
研究领域:
材料科学
·
理论化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）