POLYMER
·
2019
·
IF 3.771
Tao Xi,Yingying Lu,Xinyu Ai,Lin Tang,Lulu Yao,Wentao Hao,Peng Cui
Benzene and cyclohexane are both important raw materials in polymer chemical industry. However, they are hard to be separated via the traditional distilling methods. In this work, ionic liquid copolymerized waterborne polyurethane (IL-co-PU) membranes were proposed for the pervaporation separation of benzene/cyclohexane mixtures. The results, including swelling rate, diffusion coefficients , partial flux, permeance and selectivity, showed that the IL-co-PU membranes could preferentially absorb and transfer benzene molecules rather than cyclohexane . The ILs might have functioned as facilitated transporter in the membranes. The permeation flux and separation factor of the IL-co-PU membranes increased simultaneously with the increase of IL contents. That is, these membranes had no trade-off between permeability and selectivity, which most of the polymer membranes suffered. With consideration of the good performance and easy handling property of the IL-co-PU membranes, they are of great potential in pervaporation separation of benzene/cyclohexane mixtures.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
POLYMER COMPOSITES
·
2011
·Vol. 32
·期 9
·1343-1351
·
IF 0.998
H.L. Cai,K. Xu,H. Liu,X. Liu,Z.E. Fu,M.C. Chen
Two types of silsesquioxanes were synthesized by hydrolytic condensation reaction, and then were incorporated into polycarbonate (PC) matrix by melt blending to prepare PC/POSS hybrid composites. The study of morphology of the composites showed that octaphenylsilsesquioxane (PH-POSS) exhibited partial compatibility with PC matrix, while 3-glycidyloxypropylsilsesquioxane (EP-POSS) could react with phenolic hydroxyl groups of matrix. Thermal and mechanical properties were studied by DSC, TGA, and DMA. The result showed that the incorporation of POSS not only improved thermal stabilities of PC composites, but also retarded their thermal degradation. Si O fractions left during POSS degradations were the key factor governing the formation of a gel network layer on the exterior surface. This layer possessed more compact structures, higher thermal stabilities, and some thermal insulation. In addition, percentage residues at 700°C ( C 700 ) significantly increased from 10.8 to 15.5–22.8% in air. The storage modulus of two series of composites was slightly improved up to 90°C; furthermore, the temperature range of the rubbery state of them shifted to high temperature. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
FirePhysChem
·
2021
·
IF 0
Qi Xue,Fuqiang Bi,Junlin Zhang,Jiarong Zhang,Bozhou Wang,Minjie Wu
Two novel energetic compounds, 3-nitroxymethyl-5-(4-nitro-furazan-3-yl)-1,2,4-oxadiazole ( 4 ) and 3-nitroxymethyl-5-(4-azido-furazan-3-yl)-1,2,4-oxadiazole ( 5 ), were synthesized. Both of them were fully characterized, and the structure of 4 was further confirmed by X-ray single crystal diffraction. The thermal behaviors, detonation performances and the sensitivities of 4 and 5 were also investigated by differential scanning calorimetry (DSC), EXPLO5 program and BAM standard techniques. In addition, the electrostatic potential energy surface (ESP) was studied by Multiwfn program and density functional theory at B3LPY/6-31G (d, p). Both compounds have low melt-point, good energetic performance and mechanical sensitivity, which endow them with promising properties as plasticizing ingredients in propellant formulations.
研究领域:
有机化学
·
含能材料
·
晶体结构
·
热分析
✓ 已验证
DOI
Applied Catalysis O: Open
·
2024
·
IF 0
Huajun Wang,Jingjing Ma,Yan Li,Tengfei Wang
A series of deep eutectic solvents (DESs) with ZnCl 2 as hydrogen bonding acceptor and monoethanolamine (MEA) or acetamide as hydrogen bonding donor were prepared and used as catalysts for the reaction of glycerol and urea to synthesize glycerol carbonate (GC) without any additional organic solvent and co-catalyst. FT-IR, TGA, DSC and pH value were used to characterize the physicochemical properties of the prepared DESs. The effect of reaction temperature, urea to glycerol molar ratio, catalyst amount, and reaction time on the reaction were further investigated. The results show that ZnCl 2 :Acetamide (1:2) DES possess the highest catalytic activity because of the strong hydrogen bond network between ZnCl 2 and acetamide and the hydrogen bonding interactions between ZnCl 2 :Acetamide (1:2) and reactants, which were shown by FTIR spectra. The glycerol conversion of 93.85 % and GC yield of 90.77 % were obtained at reaction temperature of 140 °C, urea to GL molar ratio of 1:1, catalyst amount of 5 wt% (based on the GL weight) and reaction time of 2 h. Based on the experimental results and characterization by FTIR and ESI-MS, the reaction mechanism was proposed.
研究领域:
催化化学
·
绿色化学
·
有机合成
✓ 已验证
DOI
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2024
·
IF 4.7
Wang Guoqiang,Hui Yunfeng,Wei Deyu,Wang Yueying,Yu Yiheng,Shi Longqing,Zhang Mengke,Hu Jing
Poly(butylene succinate) (PBS), a biodegradable material, has excellent mechanical properties and processing properties. Brassylic acid (BA) is a kind of diacid with long chains derived from biomass. In this study, poly(butylene succinate-co-butylene brassylate) is synthesized to investigate the effects of BA on the structure and properties of PBS. The relationship between the melting temperature of copolyesters and the content of butylene brassylate units is V-shaped, which is typical of isodimorphic random copolyesters. Due to the introduction of BA, the density of unstable ester bonds in copolyesters gradually decreases and the initial thermal decomposition temperature of copolyesters gradually increases with the increase of BA. The dynamic mechanical analysis showed that the glass transition temperature of PBS was reduced by the introduction of BA. When the BA content is 25%, the copolyesters and PBS have the same crystal structure. When the BA content is 50–100%, the copolyesters and poly(butylene brassylate) have the same crystal structure, which indicates that the butylene brassylate units are easier to crystallize than the butylene succinate units. The ductility of copolyesters increases with the addition of BA. When the BA content is 50%, the elongation at break reaches the maximum (> 2000%). The copolyesters are suited for films due to high elongation at break.
研究领域:
材料科学
·
生物化学
✓ 已验证
DOI
高影响因子
Journal of Coatings Technology and Research
·
2023
·Vol. 21
·期 3
·907-923
·
IF 2.3
Lou Kunpeng,Li Siliang,Cao Yang,Li Menghang,Zou Xiaoxuan,Jing Bo
In this paper, waterborne polyurethane (WPU-SL) with high solid content and low viscosity was successfully prepared by compounding large particle size emulsion (WPU-L) with a variety of small particle size emulsions (WPU-S) by investigating the effects of small particle size type, particle size ratio, and volume ratio on the emulsion properties. A series of characterization techniques of the waterborne polyurethane was carried out by FTIR, DSC, contact angle, viscometer, particle size meter, and universal testing machine. The results show that the WPU-L/WPU-S = 5/1 emulsion has a high solid content, good emulsion stability, and excellent coating film properties. When WPU-S 1 and WPU-S 3 , two small particle size emulsions with a particle size ratio of 2.45 and 3.79, were emulsified with WPU-L, the solid content was up to 61.23%, the viscosity was only 342 mPa s, the tensile strength reached 20.97 MPa, and the adhesion grade was 5B, which was the most excellent overall performance, showing satisfactory results. Graphical
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
·
2024
·Vol. 37
·期 1
·04024444
·
IF 3.1
Xing Gong,Quantao Liu,Yingxue Zou,Xuefei Liu,Huan Wang,Pei Wan,Zhilong Cao,Shaopeng Wu
The poor adhesion of asphalt–granite limits the application of granite. This research aims to enhance the adhesion of asphalt and granite by establishing chemical connections between the hydroxyl groups on granite surface and the incompletely reacted isocyanate groups in polyurethane (PU) modified asphalt. For this purpose, end-capped PU modified asphalt (PUMA) was prepared, the adhesion mechanism between PUMA and granite was analyzed by Raman spectroscopy, the adhesion properties between PUMA and granite at different curing periods were evaluated by boiling and pull-out tests, and the wettability of PUMA on granite and its moisture sensitivity were evaluated using surface free energy (SFE) method. The findings suggested that the incompletely reacted isocyanate groups in PUMA can establish a chemical connection with the hydroxyl groups on the surface of granite. The adhesion between asphalt and granite can be greatly improved by the addition of PU, and this improvement is amplified as the curing time is extended. When the curing time is extended to 3 days, the fracture mode between asphalt and granite changed from adhesive failure to cohesive failure, and after 15 days of curing, the coating ratio of PUMA on granite following the water boiling test can be raised by 28.11% in comparison to the base asphalt. The water damage resistance of PUMA-granite system can be increased by adding PU and the adhesion work and combination ratio of the freshly prepared PUMA were increased by 55.91% and 79.45%, respectively, as compared to base asphalt. This study has great significance for enhancing the adhesion between asphalt and granite and encouraging granite application.
研究领域:
材料科学
·
土木工程
✓ 已验证
DOI
高影响因子
ChemistryOpen
·
2019
·Vol. 9
·期 3
·272-276
·
IF 2.205
Xiaoke Song,Jun-Peng Wang,Yan Song,Tao Qi,Guo Liang Li
Graphical Smart polymers : Bioinspired healable mechanochromic (HMC) materials from synthesized fluorescent polyurethane film is constructed. The mechanochromic function of the HMC materials is tunable from the hierarchical bilayer nanostructures. In addition, the broken mechanochromic function of HMC materials can be almost restored at a mild condition for high level of information encryption. Camouflage and wound healing are two vital functions for cephalopods to survive from dangerous ocean risks. Inspired by these dual functions, herein, we report a new type of healable mechanochromic (HMC) material. The bifunctional HMC material consists of two tightly bonded layers. One layer is composed of polyvinyl alcohol (PVA) and titanium dioxide (TiO 2 ) for shielding. Another layer contains supramolecular hydrogen bonding polymers and fluorochromes for healing. The as-synthesized HMC material exhibits a tunable and reversible mechanochromic function due to the strain-induced surface structure of composite film. The mechanochromic function can be further restored after damage because of the incorporated healable polyurethane. The healing efficiency of the damaged HMC materials can even reach 98 % at 60 °C for 6 h. The bioinspired HMC material is expected to have potential applications in the information encryption and flexible displays.
研究领域:
材料科学
·
生物仿生学
·
光学材料
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Jingheng Zhu,Yanli Sun,Yongbo Chen,Niangeng Wu,Ruicheng Shi,Zhongqi Ren,Qunsheng Li,Hongkang Zhao
This study investigates the vapor–liquid phase equilibria for the binary system of methyl propionate and ethanol as well as for the ternary system with three ionic liquids, [BMIM][OAC], [EMIM][OAC], and [MMIM][DMP], as extractants. The nonrandom two-liquid (NRTL) model was employed to correlate the vapor–liquid phase equilibrium data. Results indicate that each ionic liquid increases the relative volatility of methyl propionate to ethanol and effectively breaks the azeotrope at a molar fraction of 0.08. The NRTL model exhibited an average relative deviation of 2.46% for binary systems and 3.73, 4.05, and 3.60% for ternary systems. Of the ionic liquids tested, [BMIM][OAC] achieved the highest separation efficiency in the methyl propionate-ethanol azeotropic system.
研究领域:
化学工程
·
分离技术
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE FORUM
·
2024
·
IF 0
Ha Nguyen Phuong,Duyen Nguyen Thu,Nguyen Thanh Liem,Vu Anh Doan
Chitosan (CS), with its non-toxic and antibacterial properties, and Poly(ε-caprolactone) (PCL), known for its biodegradability and biocompatibility, are crucial materials in medical applications. This study proposed a solution utilizing electrospinning to manufacture fibers with nanometer-sized core-shell structures from these materials, with CS serving as the fiber core and PCL forming the shell. The influence of manufacturing technology parameters on fiber size and morphology was thoroughly researched and investigated. The solvent system used, Chloroform/Dimethylformamide (DMF), ensured complete solubility, viscosity control, conductivity, and proper solvent evaporation. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) results clearly demonstrated the morphology and internal structure of the nanofibers. The water contact angle (WCA) measurements of the fiber membrane showed almost no significant change over time, indicating strong hydrophobicity of the nanofibers. Additionally, the FTIR spectrum revealed distinct core-shell layers without any blending between them, while DSC analysis showed the thermal properties of fiber membranes. In summary, the electrospinning of nanofibers proved to be stable, producing thin fibers with an average diameter of approximately 400 nm. These findings are expected to significantly enhance the applicability of CS/PCL nanofibers across various fields, including healthcare and smart agriculture.
研究领域:
生物材料
·
医学工程
·
纳米技术
✓ 已验证
DOI
TEXTILE RESEARCH JOURNAL
·
2024
·
IF 1.6
Wenjing Zhao,Zhihui Sui,Qi Zhang,Lijian Sun,Fang Hu,Xiangyu Cao
Natural leather-based materials possess a combination of air permeability, wear resistance, and plasticity. However, conventional leather products have inherent limitations that make them unsuitable for unconventional applications. Therefore, it is necessary to develop new capabilities in order to overcome these limitations. In this study, we explored the conversion of regular leather into a high-strength product with hydrophobic properties through surface engineering. To achieve this, we synthesized polysiloxane-modified fluorinated waterborne polyurethane emulsions as functional coatings using emulsion polymerization. The structure and properties of the treated leathers were characterized using techniques such as Fourier transform infrared, thermogravimetry, X-ray photoelectron spectroscopy, X-ray diffraction, and scanning electron microscopy. The results demonstrated that the synthesized polysiloxane-modified fluorinated waterborne polyurethane successfully penetrated and combined with the fibers of the leather, resulting in excellent hydrophobicity. The water contact angle increased to 124.3°. Furthermore, the tensile strength and tear strength of unfinished leather are 875 N and 114 N, respectively. The application of waterborne polyurethane-derived functional additives as coatings resulted in a significant increase in tensile and tear strength of the leather by 60 N and 16 N, respectively. In addition, the softness of the leather increased from 7.6 mm to 10.09 mm. Overall, the use of this functional waterborne polyurethane coating will contribute to the diversification of leather applications.
研究领域:
材料科学
·
表面工程
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2010
·Vol. 293
·期 1
·73-78
·
IF 1.857
Song Hu,Qing-lin Chen,Bing-jian Zhang,Yuan-lan Liang,Xue-nong Gao
Experimental liquid–liquid equilibrium (LLE) of the water–acetic acid–sec-butyl acetate ternary system was investigated at 298.15, 303.15, 308.15 and 313.15 K and at atmospheric pressure. Separation factors were also evaluated for the immiscibility region. The NRTL and UNIQUAC models were applied to fit the experimental data for the ternary system . The binary interaction parameters obtained from both models were found to be successfully correlated with the equilibrium compositions . The UNIFAC group contribution method was employed to predict the observed ternary LLE data. It was found that four types of the UNIFAC model (UNIFAC, UNIFAC-LL, UNIFAC-DMD, and UNIFAC-LBY) did not provide a good prediction of the LLE data for this ternary system .
研究领域:
化学工程
·
热力学
·
分离科学
·
过程工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）