Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2014
·
IF 0.74
Yunyan Xue,Dandan Ma,Tianzhu Zhang,Siyan Lin,Shengnan Shao,Ning Gu
In this study, a series of comb-like methoxy polyethylene glycol (MPEG) functionalized polyurethanes (PUs) (PU–g–MPEG) were successfully prepared via ‘click’ chemistry and polyaddition reaction. The copper catalyzed Huisgen 1,3-dipolar cycloaddition was firstly carried out between 3,5-bis(hydroxymethyl)-1-propargyloxybenzene (PBM) and methoxy polyethylene glycol azide (MPEG–N3) to obtain MPEGylated diol PBM (MPEG–PBM). Then, the comb-like PUs having MPEG located on the backbones (PU–g–MPEG) were synthesized through the polyaddition of MPEGylated diol PBM and hexamethylene diisocyanate (HDI). Fourier transform infrared (FTIR), 1H NMR spectroscopy, size exclusion chromatography (SEC), and thermo gravimetric analyses (TGA) were used to characterize these synthesized MPEG-functionalized comb-like PUs (PU–g–MPEG). Compared with PU without MPEG grafts, PU–g–MPEG show a better wettability.
研究领域:
高分子化学
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材料科学
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有机合成
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表面化学
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DOI
高影响因子
FIBERS AND POLYMERS
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2020
·Vol. 21
·期 6
·1229-1237
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IF 1.797
Zhang Yiyi,Zhang Nan,Wang Qiang,Yu Yuanyuan,Wang Ping,Yuan Jiugang
Most modifications of wool focused on its surface due to the existence of the cuticle scales. For instance, chlorination, oxidation and protease treatments were used to break down or remove the scales. However, these modifications usually severely damaged the internal structure of wool. In this paper, a novel approach based on surface micro-dissolution was employed to modify the surface of wool to minimize the internal damage of wool, and improve the surface-related properties of wool. The micro-dissolution system used NaHSO 3 /urea to dissolve the scale layer of wool. After being micro-dissolved with NaHSO 3 /urea system, scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), fluorescence microscopy, Fourier transform infrared spectroscopy (FTIR), and the Allwörden reaction were utilized to characterize the treated wool. Furthermore, felting shrinkage, strength loss and wettability of the treated wool were determined. The results showed that NaHSO 3 /urea system could dissolve the scale layer from outside to inside. The fluorescence microscopic images further indicated that low concentration of NaHSO 3 /urea system can dissolve the surface of wool without the serious damage of internal structure. Moreover, the micro-dissolution system can be controlled to dissolve the scale layer on the surface of wool slightly by adjusting the reaction conditions. The presented method is simple, easy to operate, and economical, thereby can open up new directions for the surface modification of wool.
研究领域:
材料科学
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纺织工程
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化学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Yuezhou Wei,Khalid A.M. Salih,Kamal Rabie,Khalid Z. Elwakeel,Yasser E. Zayed,Mohammed F. Hamza,Eric Guibal
Alginate-PEI beads are functionalized by phosphorylation and applied for the sorption of Nd(III) and Mo(VI). The successful grafting of phosphoryl groups (as tributyl phosphate derivative) is characterized by FTIR and XPS analysis, elemental analysis, titration (pH PZC ), TGA, BET and SEM-EDX analyses. The multi-functional characteristics of the sorbent (i.e., carboxylic, hydroxyl, amine and phosphate groups) contribute in the binding of metal ions having different physicochemical behaviors. The sorption of Nd(III) is strongly increased by phosphorylation, while for Mo(VI) the enhancement is rather limited. Optimum sorption occurs at pH 3–4: maximum sorption capacity reaches up to 1.46 mmol Nd(III) g −1 and 2.09 mmol Mo(VI) g −1 ; sorption isotherms are fitted by the Langmuir equation. The equilibrium is reached within 30–40 min and the kinetic profiles are simulated by the pseudo-first order rate equation. The coefficients of the effective diffusivity are close to the self-diffusivity of Nd(III) and Mo(VI) in water; as a confirmation of the limited impact of resistance to intraparticle diffusion in the kinetic control. The sorbent is selective for Nd(III) over Mo(VI) and other alkali-earth or base metals (at pH close to 2.5–3). Metals can be readily desorbed using 0.2 M HCl/0.5 M CaCl 2 as the eluent. The loss in sorption does not exceed 5% at the fifth cycle, while desorption remains complete. A series of treatments (including acidic leachate, cementation, precipitation, sorption and elution) is successfully applied for the recovery of rare earths from Egyptian ore; with enrichment in the oxalate precipitate of Nd(III), Gd(III), Sm(III) and Eu(III).
研究领域:
环境科学
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材料科学
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化学工程
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分析化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2021
·
IF 6.953
Yingbi Chen,Jiali Tang,Shixing Wang,Libo Zhang
A chitosan-based adsorbents (CS-Ninhydrin) was prepared by grafting ninhydrin for Pb(II) ions adsorption. SEM-EDS, XRD and FTIR analysis were used to characterize the synthesized CS-Ninhydrin. The static adsorption experiments showed that CS-Ninhydrin had a good removal rate for Pb(II) ions in a wide range of pH 3 to 7, quickly reached equilibrium (120 min) and had a higher adsorption capacity (196 mg/g). Pseudo second-order and Langmuir models showed that the adsorption process of Pb(II) by CS-Ninhydrin was a single-layer chemical adsorption. Temperature experiments showed that the reaction was a spontaneous exothermic process. In the wastewater experiment, CS-Ninhydrin showed an excellent selectivity to Pb(II) ions. The reusability of CS-Ninhydrin was perfect after five adsorption-desorption cycles. The main adsorption mechanism was the chelating and electrostatic action between N and O groups in CS-Ninhydrin and Pb(II) ions. Therefore, the new adsorbent CS-Ninhydrin was expected to promote the wide application of chitosan in Pb(II) adsorption.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2023
·
IF 5
Zhiping Fang,Shaoyue Zhang,Han Wang,Xue Geng,Lin Ye,Ai-ying Zhang,Zeng-guo Feng
The core–shell structured nanofibers are routinely fabricated by coaxial solution and single-nozzle emulsion electrospinning of two polymers. Herein, the core–shell structured polymeric nanofibers were electrospun from mixed solutions of poly(ether urethane) (PEU) with poly(ε-caprolactone) (PCL) or other biodegradable aliphatic polyesters via a single-nozzle spinneret. For comparison, the mixed solutions electrospinning of poly(carbonate urethane) (PCU) with these polyesters including PCL was also conducted. The morphologies and hierarchical structures of the as-spun nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), in vitro lipase degradation, differential scanning calorimeter (DSC), and Fourier-transform infrared (FTIR) analyses. It was shown that the blends of PEU with PCL or other biodegradable aliphatic polyesters were solely electrospun into the core–shell structured nanofibers with PEU as a shell and PCL or other biodegradable aliphatic polyesters as a core. The thickness of core/shell layers from 833/606 to 193.3/54.2 μm was adjustable by varying the feeding mass ratio from 1:3 to 3:1 of PEU to PCL or other biodegradable aliphatic polyesters. In DSC analysis, the Tonset of PEU@PCL core–shell fiber was 1.31 °C higher than that of the PCL fiber, while Tm was approximate. Furthermore, changing the electrospinning solvents of PEU with PCL or other biodegradable aliphatic polyesters retained the formation of core–shell nanofibers. In contrast, the blends of PCU with these polyesters tended to form co-continuous structured nanofibers. The effects of the physicochemical properties of mixed solutions on the charged liquid droplets, whipped jets, and morphology of the electrospun nanofibers were also inspected. The creation of core–shell nanofibers from the blends of PEU with PCL or other biodegradable aliphatic polyesters was most likely due to the interaction between the inherent thermodynamic phase separation of the polymers and their external stretching kinetic phase separation during electrospinning.
研究领域:
材料科学
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纳米技术
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高分子科学
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生物医学工程
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Yuan Chen,Yuancai Chen,Yexia Qin
In the present study, we found that nanoparticles (Pd-NPs) were biosynthesized by Bacillus wiedmannii MSM ( B. wiedmannii MSM) with endogenous carbon under O 2 condition, and more favorablity under N 2 purging condition. XRD results indicated that crystal planes of Pd-NPs were attributed to Pd 0 (111), Pd 0 (200), Pd 0 (220), and Pd 0 (311), respectively. TEM and STEM-EDX results showed that the bio-reduction of Pd (II) ( k pd,1 =4.799 min −1 ) occurred predominately in periplasm space. FTIR results showed that the -COOH, -OH, and -NH 2 were the main groups participating in the removal of Pd (II). The aerobic reduction of Pd (II) by B. wiedmannii MSM was proposed, including extracellular superoxide radicals produced by NAD(P)H oxidases , endogenous electron donors, and O 2 -insensitive hydrogenase. These studies provide new methods and insights for reduction of Pd (II).
研究领域:
环境科学
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材料科学
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微生物学
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化学
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产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2024
·Vol. 25
·期 5
·1713-1725
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IF 2.2
Tan Lei,Bai Xiuzhi,Yao Rui,Fu Zengjin,Wang Jing,Wang Yicheng,Lin Tingrui,Hao Yan,Yang Hui,Yang Huimin,Sai Huazheng
The biodegradable biomass adsorbent (cellulose- g -PSS) was synthesized in LiCl/ N, N -dimethyl acetamide by the free-radical grafting polymerization reaction between sodium styrene sulfonate (SSS) and cellulose. Systematic optimization was conducted on many reaction parameters, including reaction time, monomer dosage, and reaction temperature. The grafting yield of cellulose- g -PSS was 50.16%. The chemical structures, physical, and chemical characteristics of cellulose- g -PSS were characterized by FTIR, SEM, PZC, 1 H NMR, XRD, TGA and XPS. An assessment was conducted to determine the sorption of Ce (III) on cellulose- g -PSS by changing the contact time, adsorbent dosage, pH, initial Ce (III) concentration, and NaCl concentration. The process of adsorption rapidly reached a state of equilibrium within a time frame of 25 min and was well explained using pseudo-second-order kinetic and Langmuir isotherm model. The maximum adsorption capacity for Ce (III) obtained from the Langmuir isotherm model was 84.80 mg·g −1 . The impact of NaCl concentration on the sorption of Ce (III) and XPS analysis showed that Ce (III) ions were adsorbed onto cellulose- g -PSS through ion-exchange mechanism. As a whole, cellulose- g -PSS exhibited great potential in rare earth wastewater treatment.
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
APPLIED CLAY SCIENCE
·
2020
·
IF 4.605
Yixuan Yang,Runliang Zhu,Qingze Chen,Haoyang Fu,Qiuzhi He,Jianxi Zhu,Hongping He
Multifunctional adsorbents based on montmorillonite (Mt) have been of highly concerns due to their unique 2D layer structures and impressive co-adsorption performances. To further enhance the support ability and reactivity, a strategy was developed in this study to enable the co-existence of porous nanosilica (PNS) and hydrophobic interlayer spaces in Mt structure, and a novel multifunctional adsorbent (iron modified-acidified organo-Mt, Fe-AOMt) was then synthesized, aiming to simultaneously remove hydrophobic contaminants , oxyanion contaminants and heavy metals in water. The combination of XRD , FTIR and TEM verified the co-existence of amorphous PNS and layered structure (containing intercalated surfactant) in the acidified organo-Mt (AOMt), and results of STEM-EDX revealed uniform distribution of Fe after the further introduction of Fe hydroxides to AOMt. Additionally, pore structure analyses suggested that the acid activation can obviously increase the pore volume and specific surface area of OMt. Batch adsorption experiments revealed that Fe-AOMt as a promising multifunctional adsorbent was able to effectively and simultaneously remove nitrobenzene , phosphate, and Cd(II) in the multi-contaminant system. The synergetic adsorption of phosphate and Cd(II) on Fe-AOMt suggested the formation of ternary surface complexes (≡Fe–P–Cd), while the pH-independent uptake of nitrobenzene was hardly influenced by adsorption of phosphate and Cd(II), implying dissimilar adsorption mechanisms. The co-adsorption mechanism on Fe-AOMt was further revealed via XPS . Our work provided a novel and efficient Mt-based multifunctional adsorbent with a newly-proposed structure, which was a preliminary exploration of diversifying locations and types of active sites in Mt structure.
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
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Yanjun Chen,Junqiang Shan,Yulian Cao,Xin Shen,Chenglun Tang,Ming Li,Wei Zhuang,Chenjie Zhu,Hanjie Ying
Mechanocatalytic depolymerization of lignocellulose constitutes a new frontier in biorefinery. In this study, a weak alkali-oxidation pretreatment with sodium percarbonate was employed to isolate hemicellulose from corncob, which was comprehensively characterized by FTIR, 1 H, 13 C, and 2D HSQC NMR. The influences of impregnation solvent, the type and dosage of acid catalyst, and ball-milling time on the mechanocatalytic depolymerization of hemicellulose have been systematically investigated. A mathematical model based on Kamlet-Taft parameters was first proposed to reveal the relationship between the reaction conversion and the solvent properties, and the results suggested a solvent possessing a high polarity/polarizability and Lewis basicity is favorable for the reaction. Under the optimal conditions, 97.1% conversion of hemicellulose with 93.1% selectivity of xylooligosaccharides based on xylans could be achieved within 2 h. Qualitative high-resolution ESI-MS and quantitative HPAEC analysis demonstrated the good solubility of the obtained xylooligosaccharides was ascribed to the depolymerization of hemicellulose rather than the formation of sulfonated oligosaccharides .
研究领域:
生物炼制
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化学工程
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分析化学
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生物化学
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产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2020
·
IF 3.693
Li He,Lv Kaihe,Huang Xianbin,Lu Zhen,Dong Xiaodong
Nanoscale plugging agent is essential to wellbore stability of troublesome shale formation in the drilling of oil and gas wells. In this paper, polymeric nanospheres (PNS) with a double cross-linked structure were synthesized using monomers of styrene (ST), acrylamide (AM), 2-Acrylamide- 2-methylpropanesulfonic acid (AMPS), and dimethyl diallyl ammonium chloride (DMDAAC). PNS were characterized by FTIR, SEM and TGA. The plugging performance of PNS was analyzed using nitrogen adsorption experiments and SEM. And compatibility with water based drilling fluid (WBM) was studied. Experimental results showed that PNS had a mean particle size of 133 nm, and could retain about half of the original size after high temperature treatment under 150–200°C. TGA showed that the initial decomposition temperature of PNS is around 315°C. After plugging by PNS, both the specific surface area and pore volume of the shale cuttings decreased substantially compared with those of shale samples treated with water. Thus, PNS was thermal stable in WBM under high temperature and could effectively plug shale pores. Besides, PNS was beneficial to reduce both API and HTHP fluid loss of WBM.
研究领域:
材料科学
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化学工程
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石油工程
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产品关联
DOI
PubMed
高影响因子
Materials Today Chemistry
·
2021
·
IF 8.301
X. Lu,M. Yu,D. Wang,P. Xiu,C. Xu,A.F. Lee,X. Gu
A simple and environmentally benign synthetic route to lignin-based epoxy resins is highly desirable. Alkali lignin and glyoxal are promising renewable and sustainable alternatives to phenol and formaldehyde, respectively. Their use is demonstrated to produce lignin-phenol-glyoxal novolac epoxy resins (LPG-NERs) through a simple one-pot synthesis. Flame retardancy of LPG-NERs was improved by functionalization with a N, S modified 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) material (termed DBS) obtained via nucleophilic reaction between DOPO and a N, S containing intermediate. FTIR and 1 H NMR analyses confirmed the successful fabrication of LPG-NERs and SBD. The introduction of lignin and SBD reduced crosslinking of the epoxy network, weakening mechanical properties , but conferred excellent flame retardancy (including vapor and condensed phases) as determined by LOI (34.5%), UL-94 (V-0 rating), and cone calorimetry tests (lower heat release and smoke production, and higher char formation). The SBD structure imparted a desirable vapor mechanism (blowing out phenomenon caused by the fire quenching effect of PO•/PO 2 • radicals and dilution effect from non-condensable gases such as NH 3 , N 2 , SO 2 ), while lignin (a natural biochar precursor) in synergy with SBD imparted superior charring performance.
研究领域:
材料科学
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化学工程
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高分子科学
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可持续化学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Tao Ge,Bingyi Zhou,Jingyao Xu,Yulu Wei
Ionic liquids (ILs) were selected and applied to investigate the best coal desulfurization through orthogonal tests. FTIR, XPS, SEM and contact angle tests were used to characterize the effect on the physical and chemical structures in coal for revealing the coal desulfurization mechanism by ILs-H 2 O 2 system. The orthogonal test results showed that reaction temperature and reaction time were the main influencing factors for the desulfurization rates of coal in the ILs-H 2 O 2 system, and the ILs synergy could effectively improve the desulfurization rates of H 2 O 2 . The maximum coal desulfurization rates of [BMIM][HSO 4 ], [BMIM][OTF], and [BMIM][BF 4 ] ionic liquids were 30.7%, 30%, and 33.2%, respectively. The results indicated that the alkyl groups in coal were oxidized and the contents of oxygen-containing functional groups such as hydroxyl and carbonyl increased. Coal surface underwent swelling, the internal pores increased and new pores and cracks were generated. The wettability of coal improved substantially. In addition, the physical structures changes in coal facilitated the contact between the extractant and the sulfur-containing structures. The contents of thiols and sulfides in coal significantly decreased and were oxidized to sulfoxides and sulfones, with some further oxidized to soluble sulfites or sulfates. Thus achieving removal from coal.
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）