Frontiers in Physics
·
2024
·
IF 1.9
Lu Liqun,Wang Fengjuan,Wang Yuncheng,Zhang Jiawen,Xiang Li,Liu Zhiyong,Jiang Jinyang
Hydrophobic interactions are widely applied in diverse fields, yet the effect of the degree of hydrophobicity on the interactions between hydrophobic surfaces is still unaddressed, limiting the development of functional hydrophobic surfaces. In this study, the interfacial interactions and configuration of hydrophobic chains on surfaces with ranging hydrophobicity are surveyed by surface forces apparatus. Our findings revealed that with partial hydrophobicity, a long-range electrical double-layer repulsive force pertains between surfaces, while between fully hydrophobized surfaces, only steric hindrance is observed, and the hydrophobic chains maintain configuration even after long time compression. Our findings provide useful implications for understanding hydrophobic interactions.
研究领域:
材料科学
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界面化学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2025
·
IF 6.3
Jie Liu,Jun Yang,Zijia Zhang,Qian Jiang,Lele Sun,Chaoyi Peng,Jin Wang,Li Xiang,Anlian Pan
In order to prepare polyimide materials with excellent optical transparency and UV barrier, the effects of the number and substitution position of −CF 3 groups on polyimide properties were investigated. Researchers synthesized four novel diamine monomers (BPA-O, BPA-NH 2 , BPAF-O, BPAF-NH 2 ) and synthesized eight high-performance colorless polyimides (PI-1 ∼ PI-8). On the one hand, the strong electron-withdrawing effect of −CF 3 restricts electron movement within the molecular chain, weakening the CTC effect of the molecular chain and thereby enhancing the transparency of the film. On the other hand, the ortho -substitution of −CF 3 on the imide ring induces greater twisting of molecular chains, disrupts their close packing, and thereby exerts a positive effect on enhancing the optical transparency of the film. The high bond energy of the C-F bond and the introduction of the flexible group −O- act as an “energy buffer,” suppressing UV-induced main chain breakage and achieving high UV barrier. All CPI films exhibit excellent transparency and thermal stability, with a cut-off wavelength range of 325 nm-381 nm and a transmittance range of 78.7 %-88 % at 550 nm. They have good optical properties, with T d5% distributed in the range of 511.5 °C − 533.7 °C, and the glass transition temperature ( T g ) distributed in the range of 197.3 °C-234.4 °C, demonstrating good thermal stability. Additionally, the cut-off wavelength is at a relatively high level, reaching up to 381 nm.
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产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Xianqi Hu,Zhuang Ma
In this study, we introduce a novel series of gemini surfactants with amide groups (HDAB, HDAHD, and HDAPX) and use these surfactants to decorate sodium vermiculite (Na-Vt) for the adsorption of Ibuprofen (IBP) from wastewater. Exceptional IBP uptake on organo-vermiculites (organo-Vts) is obtained, with maximum adsorption capacities reaching 249.87, 342.21, and 460.15 mg/g for HDAB-Vt, HDAHD-Vt, and HDAPX-Vt (C0 = 500 mg/L, modifier dosage = 0.2 CEC), respectively. The adsorption of IBP is well fitted by pseudo-second-order, intraparticle diffusion, and Freundlich isotherm models, verifying chemical adsorption processes with multilayer arrangement of IBP in organo-Vts. Thermodynamically, the removal of IBP on HDAHD-Vt is exothermic, while the endothermic nature aptly describes the adsorption process of HDAB-Vt and HDAPX-Vt. Moreover, organo-Vts can be stably regenerated in three cycles. Outstanding adsorption performance of organo-Vts is attributed to synergistic effects of the partition process and functional interaction, which are influenced by the steric hindrance and chain configuration of the modifier. A combined evaluation of adsorption tests and fitting calculations is employed to reveal the adsorption mechanism: (i) the incorporation of amides into the alkyl chain significantly enhances the utilization of the interlayer space in organo-Vts. (ii) Smaller steric hindrance and higher rigidity of the modifier spacer contribute to improved adsorption performance. The findings in this study rekindle interest in Vt-based adsorbents, which demonstrate comparable potential to other emerging adsorbents that are yet to be fully explored.
研究领域:
环境科学
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材料科学
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化学工程
·
水处理
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产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2024
·
IF 4.5
Huihui Xie,Han Xia,Zihan Qin,Zaichao Dong,Xin Wang,Liang Sun,Yang Liu,Yang Zhang
Polymer inclusion membranes (PIMs) exhibit great potential in the separation and recovery of valuable materials from wastewater and secondary resources. In this work the effect of alkyl chain configuration of the functional carriers on the physicochemical properties and permeability of PIMs was investigated. Three tertiary amine isomers with different alkyl chain configurations were selected as carriers: trioctylamine, triisooctylamine, and tris(2-ethylhexyl)amine. Operating conditions like carrier contents, feed solution pH, phenol concentration, and stripping solution properties were also investigated. The results obtained in this study indicate that tertiary amines with less branched alkyl chains perform better phenol transport efficiency. Furthermore, the transport efficiency decreased rapidly with increasing steric hindrance of the carriers. Trioctylamine-based PIM displayed optimal extraction efficiency of 92.8 % and stripping efficiency of 90.8 % due to its lower steric hindrance, higher hydrophilicity, and larger crystallinity. Phenol extraction and stripping efficiencies remained above 85.7 % and 80.8 % after 8 cycles, demonstrating excellent stability.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2020
·Vol. 23
·期 2
·973-982
·
IF 9.48
Weiwei Wang,Yaqin Zhang,Zifeng Yang,Zhencai Zhang,Wenjuan Fang,Donghui Niu,Hongyan He,Fei Xu
In this study, a series of high-activity imidazole-based dicationic ionic liquids (DILs) were designed and prepared as efficient catalysts for balancing the reactivity between the endo-hydroxyl group (endo-OH) and the exo-hydroxyl group (exo-OH) of isosorbide (ISO) to synthesize high molecular weight poly(isosorbide carbonate) (PIC). Meanwhile, the thermal performance of PIC was precisely optimized by regulating the chain configuration. The results showed that when the trace amounts (4.5 × 10−5 based on the ISO molar amount) of bis-(3-methyl-1-imidazole)-ethylene dibromide ([C2(Min)2][Br]2) were used, the weight average molecular weight (Mw) of PIC reached 98 700 g mol−1. It could be concluded from the results of the experiment and the stimulation that the high catalytic activity of DILs was attributed to the strong electrostatic interaction between the cation and the substrate and the effective balance of the reactivity of the endo-OH and the exo-OH. Furthermore, we found that the reduction of hydroxyl groups in the terminal groups and the increase of endo–endo (a1) structure in the repeating unit improved the thermal properties of PIC. Finally, 1H NMR, Fourier infrared spectroscopy, and density functional theory (DFT) calculations were used to verify the reaction process through anion and cation multi-site synergistic effect and a possible electrophilic–nucleophilic reaction mechanism was successfully obtained.
研究领域:
高分子化学
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材料科学
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催化
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化学工程
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DOI
高影响因子
危险品化学品经营许可证（带存储）