FLUID PHASE EQUILIBRIA
·
2021
·
IF 2.775
Zemin Yuan,Xing Zhang,Yirui Wang,Wenjie Nie,Jianguo Yin,Suxia Ma,Guanjia Zhao
For the description of the physical properties of complex fuel, fuel surrogates and their thermophysical properties are crucial to be proposed and determined. The thermophysical properties of fuel are in connection with the design and optimization of injection system in engine, and furtherly influence the performance as well as the emissions of the engine. In this study, we investigated the liquid kinematic viscosity and surface tension of the proposed binary fuel surrogates containing iso-octane with methyl hexanoate between (303.15 and 408.15) K, n-decane with methyl decanoate and methyl octanoate between (313.15 and 423.15) K at the three-mole fraction (0.2500, 0.5000, and 0.7500) close to saturation conditions, respectively, by surface light scattering method. A U-tube densimeter was utilized to determine their liquid density from (293.15 to 433.15) K. Additionally, the GROMOS force field which has been validated for similar systems in our previous study was also applied to simulate the thermophysical properties of the proposed mixtures over the same temperature range. The results show good agreement between the experimental data and the simulation, which provides more demonstration of the acceptance of the GROMOS force field for simulating the alkanes and fatty acid methyl and ethyl esters.
研究领域:
能源科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER COMPOSITES
·
2025
·
IF 4.7
Hao Liu,Chunhong Zhang,Yue Yang,Junbo Zang,Youqing Liu,Lu Wang,Lei Shang,Yuhui Ao
Synthesizing waterborne polyurethane sizing agents via an isocyanate-free route to enhance the interfacial adhesion of carbon fiber composites remains challenging. Herein, a novel aqueous non-isocyanate polyurethane (CNIPU) was prepared via amineolysis of a CO 2 -derived resveratrol-based five-membered cyclic carbonate. The CNIPU with repeating hydroxyl and carbamate segments was used as a sizing agent due to its strong chemical compatibility with epoxy resin, significantly improving the interfacial bonding strength of CF/EP composites. Results demonstrated that the sizing agent with 1.5% wt. CNIPU concentration achieved the most substantial interfacial enhancement in the composites. The interfacial shear strength was 134.14 MPa and the interlayer shear strength was 78.33 MPa, which were 147.35% and 46.25% higher than those of the unprimed CF/EP composites, respectively. The synthesis of CNIPU enables potential replacement of traditional polyurethanes with eco-friendly non-isocyanate polyurethane sizing agents.
研究领域:
材料科学
·
高分子科学
·
复合材料
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Xue Ye,Chenxi Bai,Peipei Zhang,Fuyuan Han,Junyu Xia,Xinhua Gao,Wenlin Xu,Lisheng Guo,Jie Li
Metallic atoms within metal–organic framework (MOF) materials exhibit a distinctive and adaptable coordination structure. The three-dimensional (3D) pore configuration of MOFs enables the complete exposure of metal active sites, rendering them prevalent in various catalytic reactions. In this study, zinc (Zn) atoms within Zn-based MOF materials, characterized by an abundance of valence electrons, are utilized for the transesterification of dimethyl carbonate (DMC). Additionally, the introduction of zirconium (Zr) effectively addresses the susceptibility of the MOFs’ crystal structure to dissolution in organic solvents. The formulated catalyst, Zn-10%Zr-MOF(300), demonstrates remarkable catalytic performance with 91.5% DMC selectivity, 61.9% propylene carbonate (PC) conversion, and 56.6% DMC yield. Impressively, the catalyst maintains its high performance over five cycles. Results indicate that Zr interacts with Zn, forming new coordination bonds and enhancing the catalyst crystal structure stability. Moreover, electron transfer intensifies the alkalinity of the active Zn atoms, enhancing the overall catalyst performance. This research informs the development of transesterification heterogeneous catalysts and broadens the application scope of MOF catalysts.
研究领域:
材料科学
·
催化
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Packaging and Shelf Life
·
2025
·
IF 10.6
Li Liu,Can He,Liang Zhu,Zhonghao Zhu,Kaijun Xiao
A block polyether esters (PBTF) with excellent toughness was synthesized in this study by polybutylene glycol 2,5-furandicarboxylate (PBF) as the hard segment and polytetrahydrofurandiol (PHTF) as the soft segment. The degradable and modified atmosphere films were developed by blending PBTF with poly (butyleneadipate-co- terephthalate) (PBAT). PBTF/PBAT film containing 3 % PBTF demonstrated outstanding mechanical properties and gas permeability. The tensile strength was increased by 17.21 % and the degradation properties of the film were improved. The CO 2 /O 2 gas separation coefficient was found to be as high as 13.99 and the water vapour permeability was reduced to 3.54 × 10 −13 g·cm/(cm 2 ·s·Pa), a reduction of 22.75 %. These properties contributed to maintaining a favorable atmosphere inside the package (2.6 %-3.5 % CO 2 and 15.6 %-16.7 % O 2 ) and inhibited microbial growth and nutrient loss, extending the shelf life of strawberries to 18 days (8 ℃). This degradable PBTF/PBAT modified atmosphere film has significant potential for use in fruit and vegetable packaging.
研究领域:
材料科学
·
食品科学
·
农业科学
✓ 已验证
产品关联
DOI
高影响因子
PLANT DISEASE
·
2023
·Vol. 107
·期 11
·
IF 4.5
Qiuyan Bi,Fen Lu,Jie Wu,Xiuying Han,Wenqiao Wang,Jianjiang Zhao
Pear powdery mildew (PPM), caused by Phyllactinia pyri , is one of the most serious diseases affecting production in the Hebei pear-growing region of China. Iminoctadine trialbesilate and trifloxystrobin are known to have broad-spectrum activity against a wide range of plant pathogens, including P. pyri . A total of 105 P. pyri strains were isolated from 11 cities in Hebei Province from 2017 to 2019. Iminoctadine trialbesilate and trifloxystrobin significantly inhibited P. pyri growth. Microscopic observation showed that P. pyri mycelia had different degrees of desiccation and that the conidial cell contents had been released. The sensitivities of 60 P. pyri strains to iminoctadine trialbesilate and trifloxystrobin were determined in vitro, and the average EC 50 values were 0.5773 ± 0.0014 and 1.2038 ± 0.0010 μg/ml, respectively. The average EC 50 values for 85 and 75% of the strains with continuous single peak frequency distributions were 0.4534 ± 0.0012 and 0.8124 ± 0.0039 μg/ml, respectively. These data could be used as the baseline sensitivities of P. pyri to these two fungicides. The maximum difference multiples of the sensitivities of P. pyri strains from the different cities to iminoctadine trialbesilate and trifloxystrobin were 13.5- and 17.2-fold, respectively. Cluster analysis showed that there was no significant correlation between P. pyri sensitivity and geographical origin. The field efficacies in controlling PPM were higher than 85%. These findings can improve how we monitor iminoctadine trialbesilate and trifloxystrobin resistance and improve application efficiency.
研究领域:
植物病理学
·
农药科学
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Jie Zhang,Liguo Xu,Wenhao Xiao,Yang Chen,Zhixian Dong,Jinbao Xu,Caihong Lei
With the increasing requirements concerning healthy and environmental issues of modern-day society, green chemistry and atomic economy have become the consensus of researchers and manufacturers, enabling us to explore much facile way to prepare biodegradable and biocompatible polyesters which have been widely utilized in many fields. Therefore, squaric acid (SA) a commercially available organic acid, was evaluated as the organocatlyst for the ring-opening polymerization (ROP) of ε -caprolactone (CL) to synthesize polyesters with benzyl alcohol (BzOH) as the initiator under bulk at a temperature of 80 °C. The polymerizations were demonstrated in a controlled/living character, allowing for the obtained PCLs with expected molecular weight and narrow dispersity. Moreover, PCL-based block copolymers and end-functionalized PCLs containing vinyl, alkynyl and pyrenyl chain-end were also prepared. Excitingly, SA can be facilely recovered and reused up to ten consecutive cycles without distinguishable decline in catalytic activity and MTT assay was performed to explore the cytotoxicity of the polymers.
研究领域:
材料化学
·
绿色化学
·
高分子化学
✓ 已验证
DOI
高影响因子
Journal of Renewable Materials
·
2020
·Vol. 8
·期 3
·289-300
·
IF 1.341
Li Qiaoguang,Gong Sheng,Yan Jie,Hu Hongchao,Shu Xugang,Tong Hanqing,Cai Zhiye
The plasticizer is an important polymer material additive. Non-toxic and environmentally friendly plasticizers are developed recently in order to decrease fossil fuel reserves, serious environmental pollution and the toxicity of phthalate esters. In this study, a new, efficient and
environmentally friendly plasticizer of hydrogenated rosin dodecyl ester was prepared by an esterification reaction of hydrogenated rosin and dodecanol. The influences of different reaction conditions (including different catalysts, the catalyst concentration, the ratio of the reactants, reaction
temperature, and reaction time) on the esterification yield are examined and discussed. Hydrogenated rosin dodecyl ester with 71.8% yield was synthesized under the optimized reaction conditions (1:0.8 molar ratio of rosin to dodecanol, 1 mol% tetrabutyl titanate concentration, and 210°C
for 6 h). The esterification reaction is a second-order reaction, and kinetic calculations showed that the activation energy is 39.77 KJ·mol–1. The structure of the hydrogenated rosin dodecyl ester was confirmed by FT-IR spectroscopy and 13C NMR spectrum.
Besides, the thermal stability of target product (hydrogenated rosin dodecyl ester) was also tested by thermal gravimetric analysis (TGA), which showed a good thermal stability.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 15
·8667-8679
·
IF 4.21
Hou De-Fa,Tan Huang,Li Meng-Lei,Tang Yue,Liu Zheng-Ying,Yang Wei,Yang Ming-Bo
Due to the fact that natural cellulose cannot be melted, it is still challenging to process this biopolymer via thermoplastic processing methods. Herein, polycaprolactone diol was grafted onto regenerated cellulose (RC) via hydroxyl/isocyanate chemistry in dimethyl sulfoxide to endow cellulose with thermoplasticity. By adjusting the reaction parameters including the feeding ratios of reactants and reaction time, several homogeneous cellulose grafted polyurethanes (RC-g-PU) with the degree of substitution (DS) ranging from 0.49 to 1.48 and degree of polymerization ranging from 1.84 to 3.3 were synthesized. The thermoplasticity of the obtained RC-g-PU was well characterized by differential scanning calorimetry and optical microscope. The results revealed that the prepared RC-g-PU with DS values ranging from 1.01 to 1.48 can be melted at above 168.4 °C because PU side chains can serve as internal plasticizers and prevent the restacking of cellulose chains. Eventually, the synthesized thermoplastic RC-g-PU can be processed into transparent films by hot-pressing at 170 °C. Therefore, this research constructs a melt-processable cellulose derivative by a simple and engineering method.
研究领域:
材料科学
·
生物高分子化学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2025
·
IF 7.3
Tao Zhang,Yusong Xu,Jingya Dai,Xianming Zhang
Waterborne polyurethane (WPU) is a commonly used surface finishing agent for the polyethylene terephthalate (PET) fabrics in various applications, including textiles, building interiors and vehicle interiors. However, the WPU coated PET fabrics are highly flammable. Effectively suppressing melt dripping during combustion remains a challenge, and there is a considerable demand for the self-healing property of the WPU coating in practical applications. Herein, we report flame-retardant and self-healing WPU (FRWPU/DMG) coated PET fabrics. The FRWPU/DMG are prepared by incorporating an epoxidized soybean oil-based phosphorus−containing polyol (ESO − DOPO) and a dimethylglyoxime (DMG) in the backbone. The resultant FRWPU/DMG coated PET fabrics can self-extinguish within 2 s after ignition in the vertical flame test. Throughout the whole test, there are no molten droplets and the damage length is only 7.6 cm. After being subjected to sandpaper abrasion, the FRWPU/DMG coated PET fabrics can self-heal within 24 h. Moreover, the FRWPU/DMG coating enhances the tensile strength of the PET fabric in both warp and weft directions, and demonstrates a certain wash resistance. This work provides insights into the design and preparation strategies for flame-retardant and self-healing PET fabrics.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2024
·
IF 4.7
Xu Haoming,Cheng Zhengzai,Djouonkep Lesly Dasilva Wandji,Gauthier Mario,Zuo Yingzi,Tang Wei,Xiang Leyang
The packaging industry faces a shortage of high-strength bio-derived polyesters that can rival polyethylene derivatives, resulting in the overexploitation of fossil resources. By condensing lignin-derived 2-methoxyhydroquinone with methyl 4-chloromethyl benzoate, the diester dimethyl 4,4’-(((2-methoxy-1,4-phenylene)bis(oxy))bis(methylene))dibenzoate (M) was synthesized. Using monomer M and hydroquinone hydroxyethyl ether, aliphatic-aromatic copolyesters P 1 -P 4 were prepared via melt polycondensation reaction employing various aliphatic diacids (1,4-butanedioic acid, 1,6-hexanedioic acid, 1,8-octanedioic acid, and 1,12-dodecanedioic acid). The chemical structures of the copolyesters were elucidated using FTIR and 1 H NMR, while their properties were characterized through gel permeation chromatography, differential scanning calorimetry, thermogravimetric analysis, tensile testing, and dynamic mechanical analysis. GPC analysis revealed that the average molecular weight (M w ) of copolyesters P 1 –P 4 ranged from 4.22 to 5.03 × 10 4 g/mol, while thermal property analysis indicated that the copolyesters thermal stability decreased with increasing aliphatic diacid spacer length unit. Also, the glass transition temperature (T g ) and melting point (T m ) decreased from 90 to 68 °C and 182–158 °C, respectively. Mechanical analysis showed a decrease in tensile modulus from 1740 to 1010 MPa, as well as yield strength from 76 to 54 MPa, but indicated an increase in elongation at break from 236 to 295%, owed to the growth of carbon chains which increases the proportion of flexible units in the polymer chain. The degradability study indicated a modest degradation rate from 3.9 to 5.1% after 30 weeks from P 1 –P 4 , with low ecotoxicity in all cases. P 4 , consisting of 1,12-dodecanedioic acid, exhibited the highest degradation rate, due to its low proportion of benzene units. These findings provide insights into the structure-property relationships of aliphatic-aromatic copolyesters while contributing to the advancement of high M w polyesters with performance comparable to conventional petroleum-derived polyesters, aligning with the strategy of green low-carbon, energy-saving, reduction, and sustainable development of polymeric materials.
研究领域:
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Zhixiang Yan,Huiting Yang,Shuo Zheng,Zhiyong Tan
Enhancing the dielectric properties of polymer materials plays a crucial role in reducing the volume, weight, and cost of dielectric capacitors. In this work, polyurethanes (PUs) for high dielectric performance were fabricated using poly(tetramethylene ether glycol) (PTMG) and polycarbonate diol (PCDL) as soft segments and hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), 4,4′-diphenylmethane diisocyanate (MDI), and toluene diisocyanate (TDI) as hard segment components. The effects of the type and chemical structure of diisocyanate on the microphase separation, crystallization, dielectric properties, and mechanical properties of PUs were investigated. Within the frequency range of 10 −1 –10 5 Hz, MDI-PU exhibited the lowest conductivity (7.32 × 10 −9 S·m at 10 −1 Hz) and the smallest dielectric loss (0.014 at 10 3 Hz), demonstrating excellent insulation properties. This was because the aromatic hard segments of MDI were more rigid, resulting in a tighter molecular arrangement, which facilitates the reduction of polarization loss and charge migration. In addition, the crystallinity and dielectric constant of HDI-PU were higher than those of IPDI-PU, MDI-PU, and TDI-PU. This study demonstrates the deep influence of different diisocyanates on the properties of polyurethanes, revealing the importance of hard-segment structure, crystallinity, and polarization processes in modulating the dielectric properties.
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
EUROPEAN POLYMER JOURNAL
·
2018
·
IF 3.741
Songquan Xu,Hui Zhu,Zhenjiang Li,Fulan Wei,Yu Gao,Jiaxi Xu,Haixin Wang,Jingjing Liu,Tianfo Guo,Kai Guo
H-bond donor (HBD) and base co-catalysis achieved great success in ring-opening polymerization (ROP). Parallel H-bond donor and Brønsted acid (HBD–BA) cocatalysis has been scarcely explored in ROPs. In developing the HBD–BA catalysis in to versatile toolbox for ring-opening polymerizations of wider scope and better control, tunable HBDs including boronate pinacol ester urea (BU), urea (U), and thiourea (TU) were evaluated in cooperation with trifluoroacetic acid (TFA) in HBD–BA catalytic mode. Each of the HBD–TFA co-catalyst promoted ROPs of δ-valerolactone (VL) and ε-caprolactone (CL) successfully. The catalytic performances of the HBD–TFA on the HBD part was in an order of BU > U > TU to their corresponding ROPs of VL and CL. The turnover frequencies of the catalyzed ROPs of VL and CL by BU–TFA was twice as that of TFA. The ROPs afforded homopolymers with predicted molecular weights (PVL, M n,NMR = 2.51–9.92 kg mol −1 ; PCL, M n,NMR = 2.51–11.1 kg mol −1 ) and narrow dispersities (PVL, Đ ≤ 1.16; PCL, Đ ≤ 1.18) by ratios of monomer to initiator from 20 to 100. The obtained polymers were analyzed by 1 H NMR, 13 C NMR, and MALDI-ToF MS, the results indicated the high chain-end fidelity. Chain extension experiments were conducted by a first ROP of VL/CL and second ROP of CL/VL with precise molecular weights (from 2.98 kg mol −1 to 6.15 kg mol −1 ) and narrow dispersities below 1.18. The kinetics plots showed a distinct first order relationship between ln([VL] 0 /[VL]) versus the reaction time, it indicated the controlled nature of the catalytic ROP. NMR titrations supported the proposed mechanism that HBD associated with TFA and promoted the cationic polymerization.
研究领域:
高分子化学
·
催化化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）