REACTIVE & FUNCTIONAL POLYMERS
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2024
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IF 4.5
Xiaohu Li,Wan Yan,Daruo Cao,Yunyu Zhao,Yaru Ni,Liang Fang,Chunhua Lu,Zhongzi Xu
The synthesis and application of rare earth organic complexes (REOCs) are gaining attention due to their advantages including low excitation thresholds and high luminescence efficiencies. However, their integration as functional fillers in polymer matrices is constrained by challenges related to poor dispersion and limited stability. This study introduces a novel method for synthesizing stable fluorescent polymers by co-grafting europium (Eu) complexes and the antioxidant 3,9-bis-{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl-)propionyloxy]ethyl}-2,4,8,10-tetraoxaspiro[5.5]-undecane (AO-80) onto an ethylene-vinyl acetate (EVA) matrix through an in-situ synchronous grafting strategy, aiming to address these dual challenges of poor dispersion and rapid aging. In this study, Eu complexes characterized by low excitation thresholds and high hexahydrate (EuCl 3 ) and selected ligands - 1,10-phenanthroline (Phen), alpha-thienyl trifluoroacetone (HTTA), and 4-acetoxybenzoic acid (4-ABA). Through transesterifications , the Eu complexes were successfully grafted onto the EVA chain, achieving a uniform dispersion within the EVA matrix to form fluorescent polymers. Furthermore, the incorporation of antioxidant AO-80 as a radical scavenger can significantly mitigate fluorescence attenuation. Through detailed exploration of transesterifications under various conditions, optimal grafting rates of 11.34% for EVA with Eu complexes and 22.87% for EVA with AO-80 were achieved. The synthesized fluorescent polymers of EVA synchronously grafted with Eu complexes and AO-80 have been proven to obtain markedly improved fluorescence stability and aging resistance by outdoor aging tests. Our findings not only validate the in-situ reaction grafting method as an efficient strategy for producing polymer composites with excellent fluorescence stability but also pave the way for future research aimed at overcoming the limitations of REOCs in photovoltaic and agricultural applications.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
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2019
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IF 7.181
Wenlei Xie,Fei Wan
In the current research, a porous solid base catalyst (ZIF-90-Gua) was prepared through covalent post-functionalization of zeolitic imidazolate framework ZIF-90 with organic guanidine via an imine condensation reaction. Various techniques such as XRD, SEM, FT-IR, XPS, EDX, TPD, Hammett indicator titration and nitrogen porosimetry measurements were employed to characterize the as-prepared solid catalyst. It was shown that the organic guanidine had been bound on the ZIF-90 frameworks by covalent imine linkages, and the primary crystalline structure of the imidazolium-based ZIF-90 was essentially maintained after the guanidine incorporation. This ZIF-90-Gua catalyst possessed an enhanced basicity, and interconnectivity, leading to highly catalytic activities. As a robust catalyst, the catalytic performances were evaluated in the heterogeneous transesterification of soybean oil with methanol for biodiesel production, and the maximum oil conversion to biodiesel of 95.4% was attained at reaction temperature of 65 °C, with a methanol/oil molar ratio of 15:1, catalyst dosage of 1 wt% (based on the oil mass) within reaction duration of 6 h. The solid catalyst could be easily recovered by filtration and reused for five times without significant decay of the catalytic activity, showing that it has great potential to be used as an efficient and durable catalyst for the clean production of biodiesel.
研究领域:
化学工程
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催化材料
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可再生能源
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产品关联
DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 92
·75766-75772
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IF 3.84
Lei Li,Guohua Jiang,Xiangxiang Du,Hua Chen,Yongkun Liu,Qin Huang,Xiangdong Kong,Juming Yao
A glucose-responsive and fluorescent copolymer was prepared via a one-pot method that combines RAFT polymerization and enzymatic transesterification. The as-prepared copolymer tended to self-assemble into spherical micelles that were confirmed using 1H NMR, FT-IR and GPC, and transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis. Due to the attachment of fluorescent side groups, the optical properties of the micelles were analyzed using a UV-Vis spectrometer, fluorescence spectrophotometer and confocal laser scanning microscopy (CLSM). Owing to the amphiphilic and glucose-responsive properties, the micelles could be used as carriers for loaded insulin. The insulin release behaviour was evaluated when triggered by glucose in vitro. In addition, the resultant micelles exhibited relatively lower cytotoxicity and excellent stability against a protein solution. The insulin retained its structure stability after release, investigated through circular dichroism (CD) spectra analysis. These results showed that the obtained glucose-responsive and fluorescent polymer micelles with a good biological imaging performance and biocompatibility could be one of the effective candidate carriers for controllable release of insulin.
研究领域:
高分子科学
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生物医学工程
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药学
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材料科学
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产品关联
DOI
高影响因子
GEODERMA
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2021
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IF 6.114
Kai Cai,Yongpeng Zhao,Zongjing Kang,Rui Ma,Alan L. Wright,Xianjun Jiang
Phospholipid fatty acids (PLFAs) are widely used to assess soil microbial community and metabolic activity in various environmental samples. However, the transesterification of phospholipids into PLFAs still utilize homogeneous acid/alkaline catalyst, which may increase environment risk. This study developed and validated an accurate method for the determination of PLFAs in soil utilizing pyrolysis-assisted transesterification with diatomaceous earth. The thermolysis behavior of phospholipids, optimal pyrolysis conditions, tolerance against impurities, and recyclability of porous material were evaluated. Under optimal conditions, the transesterification can complete in only 8 min, with high impurity tolerance. The repeatability (relative standard deviation (RSD) between 2.59% and 12.12%), reproducibility (RSD between 5.22% and 16.22%), and linearity ( r between 0.9259 and 0.9999) were excellent. This method was applied to analyze the PLFAs to evaluate microbial community of 1000-years paddy soil chronosequences and the relationships among soil chemical properties, enzyme activities and microbial community composition. Soil microbial biomass PLFAs increased significantly over time followed by slight fluctuation at 60–1000 years, but the ratios of soil fungal to bacterial and gram-positive to gram-negative PLFAs remained constant. In addition to soil total N and organic matter, soil enzyme activities related to N cycling metabolism also positively significantly influenced microbial communities. Overall, the developed PLFAs method using pyrolysis-assisted transesterification was environmentally friendly, efficient, accurate, stable, and suitable alternative to acid/alkaline transesterification of phospholipids.
研究领域:
环境科学
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土壤微生物学
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分析化学
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生态学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
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IF 12.5
Cui Qiao,Yunong Li,Yong Li,Yuhao Han,Li Dong,Zifeng Yang,Yifan Liu,Suojiang Zhang
MgFe-LDH/CNT-COOH composite with branch-leaf-like architecture is fabricated via in-situ co-precipitation. • MgFe-LDH/CNT-COOH shows better activity and stability compared with various solid base catalysts. • Interfacial Fe–O–C bonds boost Lewis acidity and acid-base synergy. • Interfacial electronic engineering creates acid-base synergy beyond conventional basicity-dominated paradigm. Layered double hydroxides (LDHs) are promising solid base catalysts for the transesterification of ethylene carbonate (EC) with methanol to produce dimethyl carbonate (DMC), but their catalytic efficiency is often limited by severe nanosheet aggregation and insufficient regulation of active sites. Herein, a branch-leaf-like hierarchical MgFe-LDH/CNT-COOH composite was constructed via an in-situ co-precipitation strategy. The optimized composite achieved a DMC yield of 75% with a turnover frequency (TOF) of 116.14 h −1 at 60 °C. Notably, despite its lower total basicity than pristine MgFe-LDH, the composite exhibited significantly enhanced catalytic activity, indicating that the overall basicity alone does not govern the catalytic performance. Synchrotron X-ray absorption spectroscopy and density functional theory calculations revealed that the enhanced activity is closely associated with the formation of interfacial Fe–O–C bonds between MgFe-LDH and CNT-COOH. The interfacial bonding induces electron withdrawal from Fe 3+ centers and shifts the Fe 3d-band center closer to the Fermi level, thereby strengthening Lewis acidity. The enhanced Lewis acid sites facilitate the activation of EC, while the coexisting basic sites promote methanol activation, resulting in efficient acid-base synergistic catalysis. This work demonstrates that interfacial electronic modulation in hierarchical LDH-based composites provides an effective strategy for constructing high-performance acid-base synergistic catalysts. Download: Download high-res image (261KB) Download: Download full-size image
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2015
·Vol. 133
·期 9
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IF 1.768
Xiangxiang Du,Guohua Jiang,Lei Li,Wentong Yang,Hua Chen,Yongkun Liu,Qin Huang
Glucose-sensitive and fluorescence copolymer micelles were designed and prepared via a combination of photoinitiated polymerization and enzymatic transesterification. The water-soluble photoinitiator and emulsifier 2-oxooctanoic acid self-polymerized dimer molecules under UV irradiation were characterized by mass spectrometry. The fluorescence dye (9-anthracene alcohol) and biocompatible hydrophilic chains [poly(ethylene glycol)] were introduced to the polymer chains during the photopolymerization and enzymatic transesterification processes. The as-prepared copolymers were confirmed by 1 H-NMR spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and dynamic light scattering. The resulting copolymers exhibited excellent glucose sensitivity and stability against protein. The optical fluorescence properties of the copolymer micelles were investigated with fluorescence spectrophotometry, fluorescence microscopy, and confocal laser scanning microscopy. Because of the amphiphilic feature, the micelles could be self-assembled and used to load insulin. The controlled release of insulin was evaluated and was triggered by glucose in vitro . This study provided a new strategy for fabricating functional carriers as self-regulated insulin-release systems. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 43026.
研究领域:
高分子化学
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生物医学工程
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药物递送系统
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产品关联
DOI
高影响因子
MOLECULES
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2017
·Vol. 22
·期 12
·2157
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IF 2.861
Weiwei Zhang,Huixia Yang,Wanyi Liu,Na Wang,Xiaoqi Yu
Lipases are the most widely employed enzymes in commercial industries. The catalytic mechanism of most lipases involves a step called “interfacial activation”. As interfacial activation can lead to a significant increase in catalytic activity, it is of profound importance in developing lipase immobilization methods. To obtain a potential biocatalyst for industrial biodiesel production, an effective strategy for enhancement of catalytic activity and stability of immobilized lipase was developed. This was performed through the combination of interfacial activation with hybrid magnetic cross-linked lipase aggregates. This biocatalyst was investigated for the immobilization of lipase fromRhizomucor miehei(RML). Under the optimal conditions, the activity recovery of the surfactant-activated magnetic RML cross-linked enzyme aggregates (CLEAs) was as high as 2058%, with a 20-fold improvement over the free RML. Moreover, the immobilized RML showed excellent catalytic performance for the biodiesel reaction at a yield of 93%, and more importantly, could be easily separated from the reaction mixture by simple magnetic decantation, and retained more than 84% of its initial activities after five instances of reuse. This study provides a new and versatile approach for designing and fabricating immobilized lipase with high activation and stability.Keywords:lipase;interfacial activation;surfactant;magnetic nanoparticles;cross-linked enzyme aggregates;enzyme immobilization;biodiesel
研究领域:
生物化学
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工业生物技术
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产品关联
DOI
PubMed
高影响因子
BIOMASS & BIOENERGY
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2022
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IF 5.774
Wenlu Zhang,Chunrong Wang,Beining Luo,Peihang He,Lei Zhang,Guoqiang Wu
With the aim of developing efficient heterogeneous catalysts for production of clean biodiesel through the transesterification process, a novel Mo catalyst supported on the outer surface of ZSM-22 ( x Mo/ZSM-22) was developed and synthesized successfully with the wet impregnation method. The characterization results showed that the Mo(VI) oxide species were highly dispersed on the surface of catalysts under the Mo-loading not higher than 5%, and the aggregation of the MoO 3 nanoparticles were detected above the Mo-loading of 5%. Meanwhile, the maximum acid intensity was also exhibited in the 5Mo/ZSM-22 catalyst. As a result, the catalytic performance of Mo/ZSM-22 catalysts in the transesterification of waste cooking soybean oil (WCSO) was significantly improved compared with the untreated ZSM-22 catalyst. Especially, the 5Mo/ZSM-22 showed the good activity (X WCSO of 59.29%, S Biodiesel of 99.86%), which was mainly due to the well dispersed Mo species and the larger acidity. Additionally, the 5Mo/ZSM-22 catalyst exhibits good stability and the high biodiesel selectivity , and the fuel properties of the as-synthesized biodiesel meet ASTM D6751 standards. This work provides a useful synthesis strategy of transesterification catalysts for the preparation of biodiesel.
研究领域:
化学工程
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催化
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可再生能源
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环境科学
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产品关联
DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
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2022
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IF 4.446
Jun Cao,Rong Wu,Feng Zhu,Qihui Dong,Erzheng Su
Non-aqueous biocatalysis has been expanding the application fields of biocatalysis and is playing an increasingly important role in industrial biocatalysis. Deep eutectic solvents (DESs) have been recognized as green reaction media of non-aqueous biocatalysis. To provide guidance for improving the catalytic performance of enzymes in pure DESs, Candida antarctica lipase B (CALB) catalyzed transesterification reaction was chosen as the model reaction to assess the catalytic efficiency in different series of pure DESs. The catalytic efficiency of CALB was strongly influenced by the properties of DESs. Hydrophobic DESs caused less inactivation of CALB than hydrophilic DESs. The highest yield in hydrophobic DESs reached 56.75% after 12 h. The amount of carboxyl group in hydrophobic DESs, the amount of hydroxyl group in hydrophilic DESs, and the length of carbon chain had positive impacts on the catalytic efficiency of CALB in DESs. Learning from the CALB behaviors in DESs, a preliminary attempt in rational design DESs for higher transesterification efficiency was provided. Except for reaction media, the catalytic activity of CALB in DESs was improved by medium engineering means and enzyme engineering measures, such as adding a trace amount of water, imprinting CALB with pH buffer or inorganic salt, and protecting CALB by lyoprotectants. Synergistic effect of multiple activation methods could also be observed in improving the catalytic efficiency. This study can provide insights into expanding the application of DESs in non-aqueous biocatalysis.
研究领域:
生物化学
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绿色化学
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工业生物技术
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2020
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IF 4.244
Chen Shen,Xiqing Wang,Yawei Zhu,Jiao Jiao,Sansan Bao,Ping Kou,Hongyi Pan,Yanyan Li,Yujie Fu
In this study, a novel p -toluenesulfonic acid (PTSA) based deep eutectic solvent (DES) was prepared successfully for biodiesel production by one-pot method. The DES consisting of PTSA and tetrabutylammonium bromide (TBAB) exhibited the best catalytic activity among the five prepared DESs. Central composite design (CCD) and response surface methodology were conducted to investigate reaction factors. The maximum oil extraction yield 90.33 % and fatty acid methyl esters (FAMEs) conversion yield 96.53 % were obtained under the optimal condition: microwave temperature 72 °C, microwave power 500 W, time 40 min, the ratio of liquid to seed weight 27:1 and DES amount 11 wt%. The chemical composition of FAMEs and main physical-chemical properties were investigated and the results demonstrated that the prepared biodiesel product possessed high quality. The study showed the prepared DES was a green and efficient catalyst for rapid and simultaneous extraction and transesterification seed oil for biodiesel production by one-pot method.
研究领域:
生物化学
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可再生能源
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产品关联
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Balaji Panchal,Tao Chang,Yanhui Kang,Shenjun Qin,Qiaojing Zhao,Jinxi Wang,Kai Bian,Yuzhuang Sun
A novel solid acidic polymeric ionic liquid catalyst was synthesized for ethyl esters production via the esterification of oleic acid with ethanol, normally transesterification of Pistacia chinensis oil with diethyl carbonate. Gas chromatography-mass spectroscopy analysis was used to characterize the products and optimize the reaction conditions to provide P. chinensis oil derived ethyl esters in 93% yield. Kinetic studies performed at different temperatures revealed that the conversion of P. chinensis oil to an ethyl ester follows first order reaction kinetics. The properties of ethyl esters were determined, found to meet the ASTM D6751-02. Results revealed that the catalyst had perfect utility after several runs without much loss in activity. The mild conditions (1:5) P. chinensis oil:diethyl carbonate molar ratio, 300 wt% PIL loading, 120 °C, 400 rpm, 6 h, recyclability of the catalyst make the proposed synthesis a sustainable method for the development of ecofriendly, cost-effective biofuels.
研究领域:
化学工程
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可再生资源与环境科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2016
·
IF 4.012
Xianghai Song,Yuanfeng Wu,Fufeng Cai,Donghui Pan,Guomin Xiao
A series of efficient and low-cost Li/ZnO catalysts were prepared by a simple impregnation method and investigated for the synthesis of glycerol carbonate (GC) from the transesterification of glycerol with dimethyl carbonate (DMC). The Li/ZnO catalysts were characterized using XRD, SEM, FT-IR, TG-DSC, TPD and XPS. It was found that the basicity of the catalysts highly depended on the Li loading and calcination temperature. The weak and moderate basic sites on the catalyst surfaces originated from the ZnO and Li + interaction. The strong basic sites were attributed to the substitution of Zn 2+ by Li + in the ZnO lattice, which led to straining of Zn-O bonds and the formation of [Li + O − ] species. It was the strong basic sites rather than the weak and moderate basic sites that catalyzed the transesterification of glycerol with DMC. The highest catalytic activity was observed over the ZnO loaded with 1 wt.% LiNO 3 and calcined at 500 °C. Glycerol conversion of 97.40% and GC yield of 95.84% were obtained over this catalyst at 95 °C in 4 h.
研究领域:
催化化学
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材料科学
·
绿色化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）