ACS Nano
·
2019
·
IF 13.903
Xifan Chen,Yuanzhi Zhu,Miao Zhang,Jinyi Sui,Wenchao Peng,Yang Li,GuoLiang Zhang,Fengbao Zhang,Xiaobin Fan
MXenes, a family of two-dimensional (2D) transition-metal carbide and nitride materials, are supposed to be promising pseudocapacitive materials because of their high electronic conductivity and hydrophilic surfaces. MXenes, prepared by removing the “A” elements of their corresponding MAX phases by hydrofluoric acid (HF) or LiF–HCl etching, possess abundant terminal groups like −F, −OH, and −O groups. It has been proven that the MXenes with fewer −F terminal groups and more −O groups showed a higher pseudocapacitor performance. In organic reactions, −OH and −X (X = halogen) groups could turn to ether groups in strong nucleophilic reagent. Inspired by that, herein, we report an n-butyllithium-treated method to turn the −F and −OH terminal groups to −O groups on the Ti3C2Tx MXenes. Two types of Ti3C2Tx MXenes prepared by either HF or LiF–HCl etching were systematically investigated, and a comparison with the traditional KOH/NaOH/LiOH-treated method was also carried out. It is found that most of the −F terminal groups on the Ti3C2Tx MXenes can be successfully removed by n-butyllithium, and abundant −O terminal groups were formed. The n-butyllithium-treated Ti3C2Tx MXenes show promising applications in high-performance pseudocapacitors. A record high capacitance of 523 F g–1 at 2 mV s–1 was obtained for the n-butyllithium-treated Ti3C2Tx MXenes, and 96% capacity can remain even after 10 000 cycles.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Coatings Technology and Research
·
2017
·Vol. 14
·期 6
·1325-1334
·
IF 1.557
Liu Jingcheng,Wang Kuan,Xie Yazhen,Gao Fei,Zeng Qingtao,Yuan Yan,Liu Ren,Liu Xiaoya
A series of novel partially bio-based fluorinated polyimides with double-bond end groups (BGPIs) from 4,4′-(hexafluoroisopropylidene) diphthalic anhydride, 4,4′-(hexafluoroisopropylidene) dianiline, Priamine 1074, 4-aminobenzoic acid, and glycidyl methacrylate were synthesized via a copolycondensation method in m -cresol. The chemical structure and performances of BGPIs were fully characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, gel permeation chromatography, solubility test, X-ray diffraction, and differential scanning calorimetry. It was determined that the prepared BGPIs were in the amorphous phase and readily soluble in conventional aprotic polar solvents. Additionally, the properties of as-prepared UV-cured coatings based on BGPIs were also evaluated by real-time Fourier transform infrared, thermogravimetric analysis, UV–Vis spectroscopy, and so on. Results revealed that all coatings exhibited satisfactory curing, higher adhesion, lower water uptakes, outstanding optical transparency, and fairly favorable thermal stability under a high content of biomass up to 48.9%. Therefore, these bio-based polymers could be considered as a potential sustainable candidate for high-temperature UV-curable coatings in the microelectronic field.
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 SURFACTANTS AND DETERGENTS
·
2013
·Vol. 17
·期 4
·759-765
·
IF 1.515
Qing-hua Niu,Zhi-qiang He,Yun Fang
Low-foam penetrating agents have been sought after for many industrial applications. In this paper, we were aiming at a low-foam penetrating agent with excellent wetting ability and hydrolysis resistance, various silicon-terminated penetrating agents were designed and synthesized starting from a popular commercial penetrating agent, octyl/decyl polyethylene oxide (OEO). All the products present much better low-foam performances than that of the precursor OEO. Statistically, multi-OEO substituted products present the best low-foam performance but a slightly weaker wetting ability. Except octyl/decyl polyethylene oxide trimethyl silicane, all the other five products maintain excellent wetting ability and show good hydrolysis resistance at neutral pH and ambient temperature. Di(octyl/decyl polyethylene oxide) dimethyl silicane is the preferred low-foam penetrating agent based on its structure–performance and cost, which reduced the foam volume of OEO from 75 to 4 mL (on the 100 mL volume base) at neutral pH and ambient temperature with a similar wetting ability.
研究领域:
材料化学
·
表面活性剂科学
·
工业化学
✓ 已验证
产品关联
DOI
高影响因子
DESIGNED MONOMERS AND POLYMERS
·
2018
·
IF 1.37
Liang Xu,Tianyang Lei,Boyu Jing,Yu Zang,Fengjuan Miao,Toshiki Aoki,Masahiro Teraguchi,Takashi Kaneko
Three soluble hyperbranched polyazomethines containing oligosiloxane end group HBP-PAZ-SiOn were successfully synthesized. HBP-PAZ-SiOns were used as modifiers of ethyl cellulose (EC) and polysulfone (PS) membranes. Blend membranes, HBP-PAZ-SiOn/EC and HBP-PAZ-SiOn/PS were prepared by blending the THF solution of HBP-PAZ-SiOn with ethanol solution of EC and dichloromethane solution of PS, respectively. Surprisingly, the permeabilities for CO2 of the blend membranes were more than 15–16 times higher than those of pure EC and PS membranes without any drop of pemselectivity to N2. This unusual improvement has been achieved by both enhancement of diffusivity for carbon dioxide and nitrogen by the oligosiloxane groups and enhancement of affinity of the amino groups with carbon dioxide at the end groups of HBP-PAZ-SiOn.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2025
·
IF 5.2
Huijun Xu,Ao Feng,Zhihao Huang,Rui Tan,Zefan Wang,Xiaohua Zhang,Zhengbiao Zhang
Discrete oligomers are ideal candidates for the investigation of the crystallization behaviors of polymers since the molecular weight distribution and the precision of molecular structures play a crucial role in the crystallization behaviors of polymers. We precisely synthesize discrete alternative co-oligomers (o(γ-BL-alt-ε-CL)s) with different end groups based on ε-caprolactone (ε-CL) and γ-butyrolactone (γ-BL) as monomers using an iterative exponential growth (IEG) strategy and systematically study the crystallization and melting behaviors of the o(γ-BL-alt-ε-CL)s with precise monomer sequence. The roles that the end group plays in the crystallization and melting of co-oligomers are highlighted. The o(γ-BL-alt-ε-CL)s with different end groups (tert-butyldiphenylsilyl, benzoyl, acetyl) crystallize in an extended-chain conformation. Observation on the decrease of the crystallization rate of co-oligomers with the increase of the size of the end groups is associated with the slow dynamics or slow relaxation of co-oligomer chains with the large end group. The melting–recrystallization during the heating process for the o(γ-BL-alt-ε-CL)s with small end group is attributed primarily to the reduced steric hindrance effect. For the o(γ-BL-alt-ε-CL)s with large end groups, the rearrangement of co-oligomer chains is substantially hindered by steric effects, which lead to a significant suppression of the melting–recrystallization.
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 APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 19
·50407
·
IF 2.52
Wentong Gao,Xiao Cao,Menghan Chen,Ke Chen,Shuhang Li,Bing Han
Two tertiary-amine-terminated liquid rubbers (TATPB and TATBN) containing polybutadiene and butadiene acrylonitrile are successfully synthesized and used in the modification of epoxy networks. By taking advantage of the flexibility of rubbers, the toughness of epoxy resin has been significantly improved. The addition of 60 phr TATPB and TATBN increased the impact strength of epoxy resins from 12.2 to 59.8 and 92.0 KJ/m 2 , respectively. Meanwhile, due to the dual role of tertiary amine of TATPB and TATBN in catalysis and curing for epoxies, their T g values shifted from 87.7 to 102.0 and 95.7°C, respectively. TATPB with a smaller polarity improves the toughness of the epoxy resin slightly less than TATBN with a larger polarity, but the former is more effective in increasing the T g values. This study demonstrates a novel strategy to enhance the toughness of epoxy composites as well as improve the high temperature resistance by designing the end-structure of toughening agents.
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
MACROMOLECULES
·
2017
·
IF 5.835
Zhukang Du,Biye Ren,Xueyi Chang,Renfeng Dong,Zhen Tong
Hydrophobically modified ethoxylated urethanes (HEURs) belong to an important class of telechelic associative polymers for improving solution rheological properties in many industrial fields. In this work, we describe the synthesis and solution behavior of a novel hydrophobically modified ethoxylated urethane model polymer (AzoFc-HEUR) end-bifunctionalized by Percec-type mini-dendron 3-(6-ferrocenyhexyloxyl)-5-(6-azobenzenehexyloxy)benzyl alcohol. The telechelic polymer containing both azobenzene and ferrocene moieties in aqueous solution performs multiple stimuli-responsive aggregation and rheological properties dependent on the magnitude of amphiphicity change of functional end groups upon exposure to different external stimuli such as light irradiation and/or redox reaction. It has been demonstrated that the stimuli-responsive hydrophobicity change of end groups induces a reversible micellar transition or rearrangement of micellar aggregates in dilute AzoFc-HEUR aqueous solution and a rearrangement of physical network from a dense network to a sparse network in dense AzoFc-HEUR aqueous solution and vice versa. This work is the first report of such multiple stimuli-responsive rheological properties of telechelic polymers in dense solution induced by photo- and/or redox-stimuli. The results are therefore of interest not only for the fundamental science in the controlled self-assembly of telechelic polymer in aqueous solution but also for specific applications of HEURs in the control of viscoelasticity of polymer solution, fabrication, and transmission of soft materials, medicines and cosmetics, ink for inkjet printers, and flow rate controlling systems, where careful viscosity control is necessary.
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
POLYMER BULLETIN
·
2022
·Vol. 80
·期 3
·2503-2514
·
IF 2.843
Meng Chihan,Liu Xiucai
In this paper, the polycondensation kinetics of bio-based semi-aromatic high-temperature polyamide PA5T/56 was studied in a micro-high-temperature and high-pressure reactor. The polycondensation experiment of PA5T/56 salt solution with temperature of 240–300 ℃ and initial water content of 5–30wt% was carried out. The change of end group content in the reaction process was investigated, and the relationship between polymer equilibrium molecular weight and temperature and water content was explored. The results showed that the end group concentration decreased rapidly at the beginning of the reaction and approached equilibrium after a period of time, and the higher the temperature, the higher the initial water content and the lower the equilibrium molecular weight, indicating that the polycondensation of PA5T/56 was an exothermic reaction; on this basis, a kinetics model of polycondensation reaction was established based on the literature model, it was considered that the polycondensation reaction is an acid-catalyzed third-order reaction, and the effects of temperature and water content on the equilibrium and rate of polycondensation reaction can be investigated. The kinetics model of polycondensation reaction was obtained, and the calculated results of the model were basically consistent with the experimental values.
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
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Xuechao Song,Zhaoyang Guo,Yuxi Song,Jingchun Zhang,Haiyang Gu,Naoki Yamashita,Hengyi Lu,Kenji Fukuzawa,Wenjing Hu,Tomoko Hirayama,Jiusheng Li
Polymers’ advantage of multiple adsorption sites in solid-liquid adsorption is typically constrained by their inherent steric hindrance. The research focuses on optimizing polymer adsorption on iron surfaces through terminal polar group engineering to conquer steric hindrance and boost solid-liquid interfacial adsorption efficiency. Three polyether amine derivatives are synthesized: ATPE-MA (carboxyl/amide), ATPE-P2C (pyridyl/cyano), and ATPE-NC (amide/alkyl). In-situ monitoring and theoretical calculations show that terminal polar groups synergize with multi-adsorptive sites on the polymer backbone via a “molecular clamping” effect, overcoming steric hindrance. ATPE-MA’s carboxyl terminal drives planar adsorption through strong coordination, forming a 1.7 nm dense film with the highest adsorption energy. By contrast, ATPE-NC’s weak polarity causes partial chain detachment, leading to a 0.4 nm loose layer. The evaluation of lubrication performance investigates the macroscopic performance of adsorption properties in industrial applications: stable adsorption films trigger tribochemical reactions to form iron-based/amorphous carbon composite films for continuous lubrication. ATPE-MA’s superior adsorption promotes more interfacial molecular aggregation and tribofilm formation, thus has the best lubrication performance. This cross-scale analysis of “molecular engineering-adsorption behavior-macroscopic performance” offers new approaches for designing high-adsorption functional molecules in surface engineering.
研究领域:
材料科学
·
表面工程
·
高分子化学
·
摩擦学
·
化学吸附
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 32
·2403908
·
IF 27.4
Haiyang Zhang,Yufei Han,Qingbao Guan,Zhengwei You,Meifang Zhu
The development of high-performance polymer is crucial for the fabrication of triboelectric nanogenerators (TENGs) used in extreme conditions. Liquid crystal polyarylate thermosets (LCTs) demonstrate great potential as triboelectric material by virtue of exceptional comprehensive properties. However, there are only a few specific end-groups like phenylethynyl matching the LCT polycondensation temperature (above 300 °C). Moreover, the excellent properties of LCTs rely on the crosslinked network formed with long curing time at high temperature, restricting their further application in triboelectric material. Herein, a fast-curing LCT is designed by terminating with 4-maleimidophenol possessing appropriate reactivity. The resultant LCT (MA-LC-MA) exhibits much lower polycondensation temperature (250–270 °C) and curing temperature of 300 °C within only 1 min compared to typical LCTs (cured at 370 °C for 1 h). Furthermore, the cured MA-LC-MA retains a high glass transition temperature of 135 °C, storage modulus of 6 MPa even at 350 °C, and great electrical output performance. Additionally, triboelectric measurement related to the dielectric properties that vary with crosslinked network is innovatively utilized as an analysis technique of curing progress. This work provides a new strategy to design high-performance TENGs and promotes the development of next generation thermosets in extreme conditions.
研究领域:
材料科学
·
高分子化学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LIQUID CRYSTALS
·
2017
·
IF 2.661
Ran Chen,Liang Zhao,Zhongwei An,Xinbing Chen,Pei Chen
A series of tolane liquid crystals (LCs) containing 2,3-difluorophenyl and allyloxy terminal groups have been synthesised via multi-step reactions. Their thermotropic mesophases, birefringences and dielectric anisotropy properties are discussed by comparison with the non-fluorinated analog. The results show that the allyloxy-based tolane LC 3TOV reveals a high value of the birefringence (0.29), negative dielectric anisotropy (−4.44) and a broad nematic mesophase with a low melting point and high clearing point. The effects of the terminal alkyl chains, the lateral fluoro substituents, the allyloxy terminal group and alkyne bridge on the mesomorphic and physical properties were also discussed. Meanwhile, Density Functional Theory (DFT) calculations of molecular conformation and polarisability were used to correlate the experimental findings.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）