POLYMERS FOR ADVANCED TECHNOLOGIES
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2021
·Vol. 33
·期 4
·1100-1108
·
IF 3.665
Kaiqi Li,Xiliang Liu,Long Chen,Zuochun Xiong,Chengdong Xiong,Dongliang Chen
Amino-functionalized six-membered cyclic carbonate 5-((2-nitrobenzyl) amino)-1,3-dioxan-2-one (NBAC) was synthesized with 2-nitrobenzyl group as photolabile protecting group. The following copolymerization was carried out by using l -lactide as comonomer and Sn (Oct) 2 as catalyst. The amino-functionalized polymer P(LA- co -AC) was obtained by ultraviolet irradiation of P(LA- co -NBAC) to remove the protecting group. The structures of products were confirmed by 1 H nuclear magnetic resonance (NMR) and 13 C NMR analysis. The pendant amino groups not only resulted in an enhancement of the hydrophilicity, but also played a role of antibacterial effect due to the positive charge imparted to the material.
研究领域:
材料科学
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生物医学工程
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有机化学
✓ 已验证
DOI
高影响因子
Royal Society Open Science
·
2022
·Vol. 9
·期 9
·
IF 3.653
Haijun Cheng,Chang Yu,Hongyun Wang,Xiongmin Liu,Li Ma,Fang Lai
It has been a challenge to synthesize macrolide musk in excellent yields with high purity. KF-La/γ-Al2O3 catalyst was prepared from a highly basic mesoporous framework using a mild method. The prepared KF-La/γ-Al2O3 catalyst was employed for the synthesis of cyclopentadecanolide from methyl 15-hydroxypentadecanoate. The morphology and structure of prepared catalysts were characterized using XRD, TG-DTG, SEM, EDX, TEM, BET and CO2-TPD. The results revealed that the K3AlF6 and LaOF are produced on the surface of KF-La/γ-Al2O3, and LaO can promote the dispersion of KF on the surface of Al2O3. Catalysts pore size main distribution ranges between 10 and 30 nm, the maximum CO2 desorption temperature is 715°C when the La loading is 25%. Because F− ion has a higher electronegativity than O2− ion, the KF-promoted metal oxide (Al2O3 or/and La2O3) contained more strong basic sites, compared with that of the corresponding metal oxide. The yield of cyclopentadecanolide obtained at 0.5 g KF-25La/γ-Al2O3 catalyst and a reaction temperature of 190°C for 7 h were 58.50%, and the content after reactive distillation is 98.8%. The KF-La/γ-Al2O3 catalyst has a larger pore size and basic strength, which is more conducive to the macrolactonization of long-chain hydroxy ester.
研究领域:
有机化学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2023
·
IF 5
Xu Pan,Wei Bai,Jinfang Liu,Wenfu Zhang,Xuefeng Sheng,Yang Zhou,Jianfu Zhang
Acrylate-modified aqueous polyurethane has become a widely used material due to its good physical and versatile chemical properties. However, owing to damage resulting from daily use, which often limits polymer performance, it is important to prepare a transparent and repairable polyurethane material. In this work, an acrylate-modified aqueous polyurethane based on the reversible structure of oxime–carbamate of butanedione oxime (POU) was prepared. The visible-light transmittance of the POU film could exceed 70%; its tensile strength and elongation at break could reach 3.0 MPa and 493%, respectively, and the POU film had a tensile strength of 3.9 MPa and elongation at break of 589% after repair. In addition, the POU has adjustable fluorescence properties, which makes this material suitable for potential application in the field of information encryption.
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
POLYMER
·
2016
·
IF 3.586
Jinggang Wang,Xiaoqing Liu,Yajie Zhang,Fei Liu,Jin Zhu
A series of poly(ethylene- co -1,4-cyclohexanedimethylene 2,5-furandicarboxylate)s (PECFs) with different compositions were synthesized from 2,5-Furandicarboxylic acid (FDCA), 1,4-cyclohexanedimethylene (CHDM) and ethylene glycol (EG). Their chemical structures , composition and sequence distribution were determined by FT-IR, 1 H NMR and 13 C NMR. The composition of the resulted polyesters could be controlled by the feed mole ratio of CHDM to dimethyl furan-2,5-dicarboxylate (DMFD). And for all the copolyesters, the degree of randomness (R) was close to 1, indicating their randomness. Their thermal and mechanical properties were investigated by Differential Scanning Calorimeter (DSC) and tensile testing , results showed that the crystallizability, tensile modulus and strength of PECFs were decreased with the increasing content of CHDM at first (0–59%), and with the introduction of more CHDM (76–100%) units, they were increased accordingly. However the elongation at break was changed contrarily. The barrier properties study demonstrated that although the O 2 and CO 2 permeability of PEF was increased by the introduction of CHDM, PECF-32 and PECF-76 still showed excellent barrier properties, which were better or comparable to those of PEN and PEI.
研究领域:
材料科学
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高分子化学
✓ 已验证
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2018
·
IF 2.616
Feng Cheng,Feifei Cheng,Jianyong Zheng,Guanzhong Wu,Yinjun Zhang,Zhao Wang
Only a few esterases have been used for the synthesis of optically pure fungicide. For example, ( R )-metalaxyl synthesized using esterase-involved bioreaction displays fungicide activity, whereas ( S )-enantiomer is redundant. However, the biosynthesis of ( R )-metalaxyl is currently hampered by the lower activity, selectivity and thermostability of esterase. Therefore, to obtain a better biocatalyst, several esterase genes were cloned from Pseudochrobactrum asaccharolyticum WZZ003. The esterase PAE07, among eight enzymes, was selected because it exhibited the highest hydrolysis activity toward ( R , S )-DMPM. The DNA and amino acid sequence analysis suggested that PAE07 is a new member of lipolytic enzyme family V. The enzymatic properties of PAE07 toward ( R , S )-DMPM and model substrate ( p- nitrophenyl acetate) were investigated. PAE07 was found to be a highly active esterase with excellent enantioselectivity . The reaction conditions including temperatureand pH were optimized, and the effects of metal ions, organic solvents and detergents were also investigated. Results indicated that PAE07 is a competitive candidate for ( R )-metalaxyl manufacturing.
研究领域:
生物化学
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酶工程
·
农药合成
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Sikun Fang,Wanting Zeng,Long Liu,Yuan Lyu,Fuwei Dong,Lin Wan,Yingjun Liu,Aihua Du
It is challenging to design and synthesize elastomers with both good mechanical performance and high healing efficiency because their mechanisms are mutually exclusive. This work aims to shift the trade-off between them by incorporating dynamic non-covalent bonds via 2-ureido-4[1H]-pyrimidione (UP y ) and dynamic covalent bonds via boronic ester bonds into polyurethane. The quadruple hydrogen bonds between UP y dimers serve as physical crosslinks, improving the overall mechanical properties of the polyurethane, while the boronic esters facilitate its healing. The resulting polyurethane can achieve an ultimate stress of 27.4 MPa and a healing efficiency of 90 %. The effect of healing time on the healing efficiency is modeled and discussed.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2021
·
IF 8.001
Yi-Tong Wang,Wen-Jie Cong,Ya-Nan Zeng,Yu-Qing Zhang,Jing-Long Liang,Jun-Guo Li,Li-Qun Jiang,Zhen Fang
Direct production of biodiesel by both esterification and transesterification of renewable oils with acid value (AV) of 9.6–28.9 mg KOH/g using calcined blast furnace dust is studied. Blast furnace dust calcined at 600–700 °C obviously promotes efficient biodiesel production because of the crystal form transformation from lead sulfate particles in dust into active lead oxide, lead sulfide, and lead particles. It is found for the first time that lead oxide, lead sulfide and lead particles can resist saponification from fatty acids to catalyze raw renewable oils to biodiesel with catalytic activity order as follows: lead oxide > lead > lead sulfide > lead sulfate. Biodiesel production process is optimized according to an orthogonal design with biodiesel yield of 92 wt% obtained at AV of 9.6 mg KOH/g (82 wt% after 5 cycles). Biodiesel yield of 84 wt% is achieved at AV of 28.9 mg KOH/g with acidity of 0.18 mmol/g. Calcined blast furnace dust presents potential applications in the production of biodiesel from renewable oils with high AVs.
研究领域:
化学工程
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可再生能源
·
催化材料
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2020
·
IF 5.162
De-Fa Hou,Zheng-Ying Liu,Ling Zhou,Huang Tan,Wei Yang,Ming-Bo Yang
Cellulose is an abundant feedstock with renewability and biodegradability . However, it is still challenging to manufacture natural cellulose products by environmentally friendly thermoplastic processing methods. Herein, we proposed a green approach for the heterogeneous preparation of thermoplastic cellulose grafted polyurethane (RCP-g-PU) from amorphous regenerated cellulose paste (RCP) via hydroxyl/isocyanate chemistry. First, amorphous RCP was fabricated through dissolving cellulose in sodium hydroxide aqueous solution and regenerating in polyethylene glycol, resulting in the enhancement of the accessibility of hydroxy groups in cellulose chains. Subsequently, a series of thermoplastic RCP-g-PU with the melt flow temperatures ranging from 160 °C to 226 °C were feasibly synthesized by adding hexamethylene diisocyanate into RCP without using other organic solvents . Eventually, the resultant RCP-g-PU can be directly hot-pressed into transparent films with flexibility and foldability. The reported methodology represents a sustainable route to achieve thermoplastic cellulose derivatives .
研究领域:
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TETRAHEDRON
·
2015
·
IF 2.641
Biquan Xiong,Kui Zeng,Shanshan Zhang,Yongbo Zhou,Chak-Tong Au,Shuang-Feng Yin
A novel copper-catalyzed method for the direct esterification of P(O)–OH compounds using phenols as efficient esterification reagents is illustrated. It is a simple way to generate a broad spectrum of functionalized O -aryl phosphinates , phosphonates , and phosphates from basic starting materials with moderate to excellent yields.
研究领域:
有机化学
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合成化学
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2022
·Vol. 11
·期 24
·4073
·
IF 5.561
Yingrui Ji,Dongming Lan,Weifei Wang,Kok Ming Goh,Chin Ping Tan,Yonghua Wang
With the prevalence of edible diacylglycerol (DAG) oil, which is beneficial to human, the generation of 3-monochloropropanediol esters (3-MCPDE) and glycidyl esters (GE) as well as the stability of physical properties during heat-induced processing still need to be explored. In this study, the experiment used olive-based edible oil with different contents of DAG (40, 60, and 80%) to make crackers and fry chicken. They were heated at 160 and 180 °C to determine the changes in 3-MCPDE and GE, the crackers’ hardness and gumminess, and the physical properties of the oil. During baking and frying, 3-MCPDE decreased, while the content of GE slightly increased with the prolonged heating duration. Finally, 3-MCPDE and GE were lower than 1.25 mg/kg and 1.00 mg/kg, respectively. The AV increased proportionally as duration increased and POV was below 0.30 g/100 g. In general, the changes in 3-MCPDE and GE were related to the heating temperature and duration, and not significantly (p> 0.05) related to the content of DAG.Keywords:3-MCPD ester;glycidyl ester;diacylglycerol;crackers;frying oil
研究领域:
食品科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Coatings
·
2022
·Vol. 12
·期 9
·1271
·
IF 3.236
Fuquan Deng,Shuangyi Qin,Na Liu,Wei Xu
The hydrophobic modification effect and an appropriate cost of waterborne polyurethane are regularly pursued targets of researchers. To further enhance the hydrophobic modification effect of the terminal fluoroalkyl group and control the cost, a fluorine-containing pendant group diol (DEFA) was first synthesized by the Michael addition reaction of diethanolamine (DEOA) and dodecafluoroheptyl methacrylate (G04). Next, a series of modified polyurethane latexes (TPFPU) by the terminal fluoroalkyl segments (perfluorohexyl ethanol, S104) and the pendant fluoroalkyl segments (DEFA) were synthesized by varying the DEFA dosage. Structure and performance properties of the resultants were characterized by IR,1H NMR, TEM, TGA, DSC, XRD, XPS, SEM, AFM and contact angle measurements. Results confirmed that the product could be successfully prepared using the present method. With the increase in DEFA dosage, the average particle size increased gradually. Thermal stability was enhanced and small regional crystals were probably produced. XPS and AFM results demonstrated that the degree of microphase separation and film roughness were increased with the increase in DEFA amount. Hydrophobicity of the TPFPU’s film was also increased with the increase in DEFA dosage, and it could be guaranteed when the mass content of S104 and DEFA was larger than 17.0 wt% in total mass of raw materials, which demonstrates that the terminal and pendant fluoroalkyl groups have the favorable synergistic effect on the properties of polyurethane.Keywords:fluorinated polyurethane;branched polyurethane;hydrophobicity;synergistic effect
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
FUEL
·
2023
·
IF 7.4
Qiang Lu,Yuefang Chen,Weipeng Song,Chaonan Tao,Junhua Zhang,Yong Sun,Lincai Peng,Huai Liu
Direct utilization of cellulosic material to produce specialty chemicals such as levulinate ester could greatly increase biorefinery profitability, but low-level efficiency due to its structural nature limits the strategy for industrial deployment. We report herein that adding γ-valerolactone (GVL) co-solvent during the acid-catalyzed conversion of cellulose in ethanol leads to a high reaction rate and improved catalytic activity towards ethyl levulinate (EL) production. With GVL as the co-solvent (the volume ratio of GVL to ethanol in 1:4), the yield of EL highly enhanced from 31% to 56% under mild operating conditions (170 °C for 2 h) over a low loading Al(OTf) 3 of 0.005 mol/L. The mechanistic role of GVL co-solvent to accelerate EL formation from cellulose has been fully elucidated via the combination of experimental and theoretical approaches. It demonstrates that GVL intervention not only favored the dissolution and depolymerization of cellulose, but also enabled the formation of Al species with higher acidity and catalytic activity by modulating the solvation environment, both of which are in charge of promoting cellulose conversion to EL. The activation energy barriers for cellulose depolymerization and glucoside alcoholysis have decreased by 30.8 kJ/mol and 24.8 kJ/mol, respectively. The understanding of this solvation effect can be employed to optimize the rate and yield for production of the versatile bio-based ester compound straight from cellulose valorization.
研究领域:
化学工程
·
可再生资源与环境科学
✓ 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）