Journal of Macromolecular Science Part A-Pure and Applied Chemistry
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2016
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IF 0.963
Rongpeng Liu,Bing Zhang,Liqiang Wan,Farong Huang,Lei Du
The kinetics for the reaction of diazide (4,4′-biphenyl dibenzyl azide) and diyne (dipropargyl bisphenol A) catalyzed by CuBr-PMDETA (N, N, N′, N″, N″-pentamethyldiethylenetriamine) was studied in this paper by means of nuclear magnetic resonance spectra (1H-NMR) and differential scanning calorimetry (DSC). 1H-NMR was carried out to analyze solution polymerizations under different CuBr-PMDETA ratios in DMSO-d6. The results showed that CuBr-PMDETA catalytic system was easy to be oxidation under ambient condition. However, different CuBr-PMDETA ratios influenced the catalytic efficiency and the optimal ratios were found in nitrogen gas. DSC was carried out to analyze bulk polymerizations. The results showed that the apparent activation energy (Eα) calculated by Kissinger's method was 69.2 kJ/mol, which was confirmed by Friedman's method. The two tests indicated that the catalyzed polymerization of diazide and diyne was a second order reaction.
研究领域:
高分子化学
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有机化学
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材料科学
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化学动力学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2020
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IF 7.864
Xiaobin Zhou,Xiaoling Li,Jianwen Wei,Yinming Fan,Lei Liao,Hongqiang Wang
To address the problems of the relatively high energy penalty and corrosivity of aqueous biphasic solvents, a novel nonaqueous biphasic solvent composed of 2-((2-aminoethyl)amino)ethanol (AEEA), dimethyl sulfoxide (DMSO), and N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) was proposed for CO2 capture. With optimization, this novel AEEA–DMSO–PMDETA (A–D–P) biphasic solvent could achieve a high CO2 loading of 1.75 mol·mol–1, of which 96.8% of the absorbed CO2 was enriched in the lower phase with only 49.6% of the total volume. 13C NMR analysis and quantum calculations revealed that A–D–P could absorb CO2 to form not only carbamate but also carbamic acid species, which were stabilized by DMSO via hydrogen-bonding interactions. Most products were highly polar and preferred to dissolve in polar DMSO rather than the less polar PMDETA, thus leading to the phase change. The thermodynamics results showed that the heat duty of A–D–P was only 1.66 GJ·ton–1 CO2 (393.15 K), which was significantly lower than that of the benchmark MEA (3.59 GJ·ton–1 CO2) and the reported aqueous biphasic solvents. Moreover, A–D–P presented a noncorrosive behavior to steel after CO2 saturation, clearly showing its superiority over MEA and the aqueous biphasic solvents. Therefore, with superior properties of energy savings and noncorrosiveness, the A–D–P biphasic solvent could be a promising candidate for CO2 capture.
研究领域:
化学工程
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环境科学
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产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
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2019
·Vol. 10
·期 29
·3996-4005
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IF 4.76
Feifei Li,Wanting Yang,Mengmeng Li,Lin Lei
A simple white light-emitting diode (LED) induced controlled radical polymerization (CRP) with an in situ bromine–iodine transformation was successfully conducted via organocatalysts. N,N,N′,N′′,N′-Pentamethyldiethylenetriamine (PMDETA), tributylamine (TBA), and hexamethylphosphoric triamide (HMPA) were employed as organocatalysts in this CRP system due to their green, inexpensive, easy-to-handle and highly reactive features. All the three organocatalysts exhibited high efficiency in this CRP system. The polymer molecular weight and distribution (Mw/Mn = 1.02–1.19) of poly(methyl methacrylate) were satisfactory up to fairly high conversions at room temperatures. Well-defined copolymers demonstrated living features of controlled radical polymerization which also indicated that functional methacrylates were also appropriate for this system. Various solvents were added in this CRP system which widely broadened the applicability. Notably, using PMDETA as an organocatalyst for both in situ bromine–iodine transformation CRP and ring-opening polymerization (ROP), poly(methyl methacrylate)-b-poly(L-lactide) (PMMA-b-PLLA) was successfully synthesized in “one-pot”.
研究领域:
高分子化学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Lijian Jin,Lingxiao Zhan,Xueyan Hou,Shangzhi Xie,Lina Gu,Hangqi Yang,Xin Wang,Dawei Hou,Jianchong Shen,Liqun Zhang,Linjun Yang
Nonaqueous biphasic solvent has remarkable energy-saving potential. The weak force between N, N, N′, N″, N‴-pentamethyldiethylenetriamine (PMDETA) and Dimethyl sulfoxide (DMSO) contributes to facilitating the separation between DMSO and PMDETA, thereby enabling efficient liquid–liquid phase separation. Nevertheless, the weak interactions of PMDETA with other solvent molecules pose considerable challenges in the formulation of fresh homogeneous phase solutions. This study proposes a strategy to enhance PMDETA dissolution by introducing a solubilizer into a hybrid phase splitter, thereby increasing the concentration of PMDETA in the solvent. With the addition of a small quantity of solubilizer, the absorption, regeneration, and phase separation performance among the absorbents are comparable. The phase separation performance is influenced by the number of hydrogen bonds formed by the solubilizer, and the concentration of solubilizer in the lower phase is dependent on its hydrophobicity. Characterization using 13 C NMR and FT-IR indicates that CO 2 products primarily exist in the form of MEACOO − /MEAH + . Through DFT and molecular dynamics simulations, the impact of the solvent environment surrounding Ethanolamine (MEA) on the MEA + COO − deprotonation reaction is analyzed. While PMDETA offers a more favorable proton acceptance energy compared to MEA, the limited opportunities for PMDETA to come into contact with MEA molecules may be the primary hindrance to its participation in the reaction. Significantly lower corrosivity and regeneration energy requirements for non-aqueous biphasic solvents compared to 30 wt% MEA make them ideal candidates for energy-efficient, low-corrosivity CO 2 capture.
研究领域:
化学工程
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环境科学
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材料科学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2015
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IF 2.711
Liping Jiang,Xuyang Zhou,Guyun Wei,Xiaoduo Lu,Weiping Wei,Jianhua Qiu
Polymer brushes based on poly(glycidyl methacrylate) (PGMA) have been successfully grafted from the surface of silica coated iron oxide (Fe 3 O 4 @SiO 2 ) nanoparticles via surface-initiated activators generated by electron transfer atom transfer radical polymerization (SI-AGET ATRP). The size of the nanoparticles could be adjusted from 7.3 to 9.6 nm by varying the precursor concentration of iron(III) acetylacetonate. The Fe 3 O 4 nanoparticles possessed a highly crystalline structure, and the saturation magnetization of the as-prepared magnetite was strongly related to the particle size. Furthermore, the grafted PGMA content on the magnetic nanoparticles could be controlled by varying the ligand to transition metal ratio in a N , N , N ′, N ″, N ″-pentamethyldiethylenetriamine (PMDETA)/CuBr 2 catalyst system. The maximum grafted content was 23.1% at a ratio of [PMDETA] 0 /[CuBr 2 ] 0 = 2:1.
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
POLYMER
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2025
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IF 4.5
Zhuoxin Wen,Xiaoyue Yang,Meiqi Wang,Jia Yang,Manman Zhao,Zhanxiong Li
In this paper, 2-bromoisobutyryl bromide (BIBB) was used to gain access to the active site of an atom transfer radical polymerization (ATRP) reaction on fiber surface to prepare a Cotton-Br macromolecular initiator. It was then used to trigger the ATRP polymerisation of styrene under the PMDETA/CuBr system. The influence of monomer concentration, bath ratio, and grafting time on the in situ generation of micro- and nanomorphic coatings on fiber surfaces were also investigated. Cotton-PS, a cotton fabric with controllable rough morphology of fiber surface, was obtained through the adjustment of grafting reaction conditions. Energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR) and atomic force microscope (AFM) test proved that grafting reaction was successful. The C-Br on coating surface can condensed with perfluoropolyether carboxylic acid (PFPE-COOH), and the ensuing reaction introduces Diazabicycloundecene (DBU), thereby activating the PFPE-COOH. Under mild reaction conditions, this process produces superhydrophobic cotton fabrics. The effect of different molecular weight PFPE-COOHs on hydrophobicity was also investigated during chemical modification. The contact angle (CA) of modified cotton fabric increased from 144.8 ± 3.6° to 155.2 ± 3.5° after chemical modification with PFPE-COOH, exhibiting superhydrophobicity. The finished fabric showed excellent oil-water separation performance. Subsequent to the completion of 10 cycle tests, its oil-water separation efficiency was maintained at 98.6%.
研究领域:
材料科学
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高分子化学
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纺织工程
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表面改性
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疏水材料
✓ 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）