JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
KunKai Ma,Xiaoshuang Li,Xianger Xia,Yezhen Chen,Zhenchao Luan,Hongyue Chu,Bing Geng,Mei Yan
The preparation of solvent resistant nanofiltration (SRNF) membranes with high permeance and retention is required for accurate chemical separation, yet the solvent resistance of the membranes still needs to be improved. Fluoropolymers with strong weather resistance and chemical stability are expected to improve the solvent resistance of solvent resistant nanofiltration membranes . However, the application of fluorinated monomers in interfacial polymerization has been limited because they are water-insoluble. In this paper, ionic liquids were added to the aqueous phase to improve the solubility of hexafluorobisphenol A (BPAF). Trimesoyl chloride (TMC) was used as organic phase monomer. Fluorinated polyarylester thin film composite (TFC) membranes were synthesized on polyacrylonitrile (PAN) base membranes utilizing interfacial polymerization. The results confirmed that the surface morphology and roughness of TFC membranes could be regulated by adding fluorinated monomer. The membrane sample PAN-F-0.5 exhibits a high permeance for methanol up to 124.05 L m −2 h −1 bar −1 . The resulting membrane possesses a molecular weight cut off (MWCO) of∼450 g mol −1 . PAN-F-0.5 still showed excellent performance after continuous immersion in DMF for 90 days (room temperature) and 7 days (80 °C), respectively. The results show that the TFC membrane has excellent filtration performance and solvent resistance.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2020
·
IF 4.469
Xiaoqiang Zheng,Ai-min Pang,Yu Wang,Wei Wang,Yongping Bai
Novel UV-curable methacrylate functionalized fluorosilicone resin (MAFSR) and sulfhydryl functionalized fluorosilicone resin (SFSR) were synthesized respectively. The molecular structure, UV curing process, thermal properties and surface properties were studied. Further application as protective coatings in the field of printed circuit board (PCB) was explored. Results show that the MAFSR with more than 30 wt % SFSR possess a high carbon-carbon double bonds conversion above 95 % after 15 s UV exposure. Besides, the surface energy of the coatings is as low as 11.5 mN/m, showing excellent hydrophobicity . The XPS results further reveal that the migration and orientation of the fluorine groups to the surface is an intrinsic reason for low surface energy. In addition, the coatings also demonstrate excellent heat resistance and solvent resistance . This study shows that UV-curable fluorosilicone resins are presumably promising special protective coatings for PCB.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2020
·
IF 7.183
Chengyu Yang,Weixing Xu,Yang Nan,Yiguang Wang
Solvent-resistant nanofiltration (NF) membranes have numerous application prospects. In this study, a novel solvent-resistant nanofiltration membrane with a double layered polyamide structure was prepared for efficient desalination. The substrate was polyimide crosslinked with m -phenylenediamine (MPD), and the surface layer was polyamide prepared by typical interfacial polymerization. The crosslinking was confirmed by Fourier transform infrared spectroscopy . Investigation of the effects of different reaction conditions on membrane performance showed that the optimal reaction conditions were found to be: 5% aqueous MPD solution with crosslinking time of 10 min and piperazine concentration of 0.1% (m/v). The rejection rate for sodium sulfate and sodium chloride were 99.13% and 97.45%, respectively. The membrane morphologies were studied by scanning electron microscopy and atomic force microscopy . The membrane showed electronegativity in the pH range of 3.0–10.0 and its contact angle was 54.28°, indicating excellent hydrophilicity. After soaking in several solvents for a week, the membrane still had a high rejection rate of more than 90% for Na 2 SO 4 , demonstrating its excellent solvent resistance .
研究领域:
材料科学
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环境工程
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DOI
高影响因子
ADVANCED MATERIALS
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2021
·Vol. 33
·期 36
·2102096
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IF 30.849
Qiang Ma,Shenglong Liao,Yingchao Ma,Yanji Chu,Yapei Wang
Elastomers presenting good elasticity, ductility, and chemical resistance at low temperatures can serve as superior performers for explorations in extremely cold environments. However, no commercially available elastomer to date can comprehensively fulfill those demands. Here, a perfluoropolyether (PFPE)-based network crosslinked by dynamic urethane chemistry is demonstrated, which may satisfy the demands of application in ultracold environments. As the crucial constitute in such a crosslinked network, PFPE provides the elastomer with excellent elasticity at a temperature down to −110 °C and outstanding ductility within the cryogenic temperature range. Importantly, the high proportion of fluorocarbon segment also provides wonderful compatibility to most organic solvents, accounting for the low-swelling characteristics of the elastomer in sealing applications. Furthermore, the dynamic crosslinking feature allows the cured elastomer to be reprocessed like thermoplastic polymers, which affords great promise to recycle and reuse the elastomer after its disposal. Inherently, this elastomer would inspire a worldwide interest in the design of elastic devices that are adaptable to extremely low temperature.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER INTERNATIONAL
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2011
·Vol. 61
·期 1
·111-117
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IF 2.056
Bing Fang,Kai Pan,Qinghan Meng,Bing Cao
This study investigated the preparation of polyimide solvent-resistant nanofiltration membranes by a two-step method (casting the membrane first and then crosslinking by the thermal imidization method). The influences of polymer concentration, thickness of membranes, temperature of the imidization, phase inversion time and thermal imidization procedure were studied. The membranes with the highest rejection rate of Fast Green FCF (molecular weight 808.86 g mol −1 ) were prepared in the following conditions: polymer concentration 13 wt%, phase inversion time 1 h, membrane thickness 150 µm and thermal imidization procedure 200 °C for 2.5 h, 250 °C for 2 h and 300 °C for 2 h in a vacuum environment; the heating rate was 5 °C min −1 . The membrane was stable in most of the solvents tested and the fluxes of some common solvents were equal to or higher than a number of commercial solvent-resistant nanofiltration membranes. A much higher rejection of dyes in water than in methanol was observed in the filtration experiments and a new way to explain it was developed. Copyright © 2011 Society of Chemical Industry
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2019
·
IF 0.67
Bo Ning,Jun-Wen Cao,Xiao-Teng Zhou,He Qin,Ling-Xiao Li,Cheng-You Kan
A novel, reactive, yellow fluorescent organosilicon dye, N-propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide, is designed and synthesized and is used to fabricate a covalently yellow fluorescent silicone oil by polycondensation of hydroxy-terminated polydimethylsiloxane. The chemical structure and optical properties of the N-propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide and covalently yellow fluorescent silicone oil are characterized by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, mass spectrometry, Fourier transform infrared, UV–Vis, and fluorescence spectra. The results indicate that the fluorescence quantum yields of N-propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide and covalently yellow fluorescent silicone oil are 2.61% and 3.5%, respectively. The λmax values of their dichloromethane solutions are 416 nm, and their λex and λem are 430 and 509 nm, respectively. Furthermore, covalently yellow fluorescent silicone rubbers are prepared using tetraethoxysilane as a cross-linker, and some of their properties are investigated. Thermogravimetric analysis and dynamic mechanical analysis show that heat resistance and tan δ of the covalently yellow fluorescent silicone rubber are improved in comparison with silicone rubbers without N-propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide moieties. Solvent extraction experiments indicate that the solvent resistance of the covalently yellow fluorescent silicone rubber is much better than that of noncovalently yellow fluorescent silicone rubber.
研究领域:
材料科学
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化学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2023
·
IF 6
Qingming Kong,Longfei Guo,Kaiqiang Zhang
Tough polyamides are crucial materials useful in many fields such as water purification and automobiles. Here we present a synergistic strategy to toughen polyamides by mechanistic interplays between aliphatic and aromatic supramolecular segments. The aliphatic monomer of adipic acid dihydrazide (ADH) and the aromatic monomer of 4,4′-oxydianiline (ODA) were subjected to low-temperature solution polycondensation with terephthaloyl chloride to synthesize tough aromatic–aliphatic polyamides in one step. Tailoring the mismatched supramolecular interactions between ADH and ODA segments enabled the precise control on the crystallinity, microphase separation structure and energy dissipation ability of the polymers. By varying the ratio of ADH segments to ODA segments, we obtained the optimal aromatic–aliphatic polyamides with high strength (ultimate engineering stress, 43.3 MPa), high toughness (31.2 MJ m −3 ) and remarkable solvent resistance due to the reliable supramolecular crosslinks. This synergistic toughening strategy is potentially useful to guide the design and development of strong and tough polymeric materials.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2019
·
IF 3.42
Jiating Wen,Zhe Sun,Haojun Fan,Yi Chen,Jun Yan
A series of fluorine-containing water-based polyurethane (FWPU) were synthesized by using fluoro alcohol-terminated isocyanate trimer (F-HDIT) prepared from 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol (TFO) and hexamethylene diisocyanate trimer (HDIT). The structure of F-HDIT and the wetting and spreading ability, hydrophobic and solvent-resistance properties of FWPU were investigated in detail. The results indicated that with the increase of F-HDIT, the latex particle size, the water/solvent resistance and elongation at break of FWPU increased. More interestingly, the wetting and spreading ability on non-polar substrates was enhanced with the introduction of F-HDIT and the surface tension of FWPU film/latex was decreased by 69.5%/17.3%. Meanwhile, the water/methylene iodide contact angles were increased from 54.0°/34.1° to 121.8°/90.7° respectively, showing good hydrophobic and solvent-repellence characteristics.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Wenzhong Ma,Taiyu Li,Chao Jiang,Peng Zhang,Li Deng,Rong Xu,Qi Zhang,Jing Zhong,Hideto Matsuyama
Pervaporation (PV) performance of polyimide (PI) membranes has been attempted for the recovery of high concentrations of aprotic solvents, such as N, N-dimethyl formamide (DMF) and N, N-dimethylacetamide (DMAc). In this work, we explored the effect of chain structure on the solvent resistance and pervaporation performance of hydrophilic pyromellitic dianhydride (PMDA) and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) based polyimide membranes. According to the Hansen solubility parameters and membrane formation morphologies, we selected five aprotic solvent resistant PI membranes with different chain structures. It was found that the swelling degrees in DMF and DMAc was principally determined by the elasticity modulus of the PI membrane, and was significantly influenced by the polymer chain structure. The flexible linkages (such as –O CH 2 and CH 2 ) suppressed the PI chain packing, which resulted in the d -spacing and fractional free volume ( FFV ) of PMDA based PI membrane was higher than BTDA based PI membrane. BTDA-BZD membrane had the highest elasticity modulus together with the lowest d -spacing value (4.68 Å) due to its symmetric intermolecular interaction and rigid chain structure. PV experiments were conducted with DMF/water and DMAc/water mixtures over a wide range of temperatures (30–60 °C) with 90 wt% solvent concentration. The BTDA based PI (M4) composite membrane showed the highest separating factor around 275 at 30 °C in DMAc solution, which was much higher than in DMF solution (the separating factor is about 70). Furthermore, the chemical and thermal stability test for the PI composite membranes in the presence of the feed solvent under the PV process demonstrated the excellent separation stability in DMAc solution.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2020
·Vol. 55
·期 27
·13472-13486
·
IF 3.553
Chen Tao,Xu Mengfan,Zhao Liming,Wang Lejun,Qiu Yongjun
Electrospinning is a highly efficient mild method to obtain stereocomplex poly(lactic acid) fibers from blends of high molecular weight (MW) poly( L -lactic acid) (PLLA) and poly( D -lactic acid) (PDLA). However, high MW PLAs are expensive and proved difficult to avoid homocrystallites which weaken the performances. Here, di-stereoblock poly(lactic acid)s (di-sb-PLAs) with low MW of 10 4 g mol −1 were synthesized and electrospun into membranes. The stereocomplex (sc) crystallites were induced by sintering the amorphous as-spun membranes at 200 °C, and further improved by applying 1 MPa pressure which promoted the segment migration across fiber intersections and welded the fibers by forming new sc crystallites. Due to more readily crystallize at molecular level than the blend of PLLA and PDLA, the sintered di-sb-PLA membranes exhibited higher thermal stability, better tensile strength, and were more stable during multiple cycles of selective separating solvent and water mixtures. Increasing MW of di-sb-PLA positively affected the membrane properties and inhibited dramatical embrittlement that occurred in sintered membrane of PLLA and PDLA blend.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2017
·
IF 5.951
Yanchao Xu,Fangjie You,Hongguang Sun,Lu Shao
Herein, a mussel-inspired polydopamine (PDA) coating layer has been first explored as a separating layer for organic solvent nanofiltration (OSN). A PDA based separating layer was constructed on polyimide (PI) support via dopamine coating. The subsequent membrane was then treated with 1,6-hexanediamine for cross-linking on both the PDA layer and PI support. Fourier transform infrared (ATR-FTIR) and X-ray photoelectron (XPS) results indicated the deposition of PDA on support and the cross-linked structures of both PDA and PI. Scanning electron microscopy (SEM), atomic force microscopy (AFM), water contact angle, and surface energy measurements were further employed to characterize the morphologies and surface properties of the composite membranes. After an optimized coating time of 4 h, the resultant membrane showed an EtOH permeance of 0.91 L m–2 h–1 bar–1 and a RB rejection of 99%. More importantly, the composite membrane also exhibited good performance for dyes separation from a wide range of solvents including challenging polar aprotic and strongly swelling solvents, such as dimethylformamide and acetone. In addition to demonstrating a facile and effective OSN membrane fabrication approach, this study may stimulate the bioinspired design of a composite membrane for sustainable applications.
研究领域:
材料科学
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环境工程
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生物仿生学
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产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
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2014
·
IF 1.09
Yongpeng Wang,Haibo Zhang,Mengzhu Liu,Yingshuang Shang,Yingjian Lin,Zhenhua Jiang
A novel poly(arylene ether sulfone) (PAES) with pinacol phenylboronate pendants (PAES-B) was prepared by the borylation of brominated PAES (PAES-Br). The reaction was carried out under mild conditions in the presence of cuprous iodide and tri-n-butylphosphine in tetrahydrofuran solution. After heat treatment at 150°C for 132 h, the PAES-B exhibited an interesting solvent resistance. Fourier transform infrared spectroscopy (FTIR) and thermal analysis were performed to investigate the reason. FTIR spectra showed that heat treatment could facilitate losing of pinacol groups and formation of phenylboronic acid in the polymer. Meanwhile, differential scanning calorimetric (DSC) curves demonstrated that the polymer had cross-linking behaviors during heat treatment. In addition, the thermal oxidative stability of PAES-B was researched by the thermogravimetric analysis (TGA).
研究领域:
高分子化学
·
材料科学
✓ 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）