FUEL
·
2024
·
IF 6.7
Lingrui Cui,Xu Liu,Mannian Ren,Jun Xu,Fahai Cao
Nickel and vanadium in crude oil adversely affects the quality of petroleum coke and refining process. Polymer brushes bearing high-density ligands have shown promising nickel removal ability. In this work, submicron polybutadiene (PB) grafted by aminodithio- carbamate acrylamide (PAMDTC@PB) was prepared and characterized by the infrared spectroscopy, dynamic light scattering, and elemental analysis. Based on results of molecular simulation, PAMDTC was selected as ligand molecule at first. Then the nickel and vanadium removal rates by PAMDTC@PB and traditional polyacrylic acid brushes (PAA@PB) were evaluated through the electric desalination process, both in the model and real oil samples. The result shows that S atom in AMDTC is most likely to chelate with metal porphyrin compounds and AMDTC molecule presents highest chelating activity. Compared with PAA@PB, the removal rate of Ni and V porphyrin compounds with the aid of PAMDTC@PB increases significantly, with an optimized removal rate of 46.91 % and 56.81 %. To achieve better metal removal efficiency and higher utilization rate of prepared polymer brushes, sodium dimethyl dithiocarbamate (SDD) is introduced into the electric desalination process as a adjuvant. The results indicate that the addition of SDD leads to a increment of 10–30 % to the removal rate of Ni and V and a reduction of brush dosage by 200–400 ppm in the electric desalination process, exhibiting great potential of industrial applications of novel desalination process with adjuvant.
研究领域:
化学工程
·
材料科学
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产品关联
DOI
高影响因子
POLYMER
·
2025
·
IF 4.5
Shengjun Zheng,Chengcheng Zeng,Jianhu Zhang,Yajun Luo,Feiyan Gong,Fude Nie
Improving the interfacial interaction between explosive crystals and the polymeric binder was essential for enhancing the mechanical properties of polymer bonded explosives (PBXs). In this study, the surface of the 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) crystal was initially coated with a polydopamine (PDA) layer, which served as an active platform for anchoring the 2-bromoisobutyryl bromide as an ATRP initiator; then, the co-polymer chains composed of Acrylonitrile(AN), 2-Hydroxyethyl methacrylate (HEMA) and 2-(Dimethylamino)ethyl methacrylate (DMAEMA) were grown through surface-initiated atom transfer radical polymerization (SI-ATRP) from the surface of TATB modified with ATRP initiator. The formation of the PDA, ATRP initiator and polymer brush coating layer on the surface of TATB was confirmed through SEM, TEM, XPS and contact angle tests. After incorporating a rigid-flexible gradient interface structure composed of PDA and polymer brush layer, the PBXs exhibited enhanced mechanical strength and creep resistance. Compared with the pristine TATB-based PBXs, the static mechanical properties, including tensile and compressive strength, of TATB@PDA@PAN-co-PHEMA-co-PDMAEMA based PBXs were increased by 36.7% and 23.9%, respectively. The maximum creep strain decreased by 39.4% at 30 °C and 14.6% at 75 °C. Additionally, the coefficient of thermal expansion decreased by 8.37%. This study presents an universal method for enhancing the mechanical properties of PBX by integrating PDA chemistry with SI-ATRP.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Zhonglin Cao,Tiansheng Gan,Gaixia Xu,Chunfeng Ma
Inspired by fish skin, biomimetic self-renewal poly[(ethylene oxide)-co-(ethylene carbonate)] (PEOC) brushes with protein resistance had been prepared via surface-initiated ring-opening polymerization (ROP). The results of hydrolytic degradation indicated that the PEOC brushes could degrade in artificial seawater. Ellipsometry, X-ray photoelectron spectrometry, and contact angle results demonstrated that the PEOC brushes degrade uniformly. By using a quartz crystal microbalance with dissipation, we studied the protein adsorption on the surfaces in artificial seawater at different degradation times. After 24, 48, 96, and 168 h of degradation, the PEOC surfaces showed nearly zero Δf and ΔD for bovine serum albumin, lysozyme, and fibrinogen. More importantly, there was a notably lower density of microorganisms adhered to the surface modified with PEOC compared with that of the surface without PEOC in natural seawater. The current study showed that the PEOC brushes exhibit a self-renewal property with persistent protein resistance and prevent the adhesion of microorganisms. Such a biomimetic polymer had a great potential in marine antibiofouling.
研究领域:
材料科学
·
生物医学工程
·
海洋科学
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产品关联
DOI
PubMed
高影响因子
FUEL
·
2018
·
IF 4.908
Jun Xu,Limei Chen,Tong Geng,Mannian Ren,Shizhong Wang,Zhijun Song,Fahai Cao
Nickels in crude oil often deactivate the hydrocracking and catalytic cracking catalysts. Strong acids are widely applied to remove these nickels, although they cause severe corrosion to the subsequent catalytic cracking and processing equipment. Polymer brushes bearing specific groups which can adsorb nickel ions are considered as desirable non-corrosive nickel removal agents. In this work, micro-sized spherical polymer brushes bearing imidazole groups (PVIm@SiO 2 ) are first applied to remove trace nickels in crude oil with the help of electric demulsification . The effects of polymer brushes concentration, oil/water ratio and electric demulsification temperature on nickel removal efficiency are investigated. Compared with the monomer (VIm) and polymer (PVIm) bearing imidazole groups, polymer brushes exhibit a much higher nickel removal efficiency than the other two, which is approximately 66.7%. In addition, the regeneration of polymer brushes are achieved by a rapid and simple process using diluted HCl. As well as, the removal efficiency of Ni remains 62.5% in 5 consecutive cycles. Consequently, these spherical polymer brushes bearing imidazole groups are reasonable nickel remover for crude oil.
研究领域:
化学工程
·
材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2018
·Vol. 6
·期 12
·1734-1743
·
IF 4.776
Shuhao Wang,Fei Zan,Yu Ke,Gang Wu
Introducing or grafting molecules onto biomaterial surfaces to regulate cell destination via biophysical cues is one of the important steps for biomaterial design in tissue engineering. Understanding how cells feel the substrate makes it easier to learn the mechanism behind cell–material interaction. In this study, on a glass substrate, we constructed poly-phenoxyethyl methacrylate (PHEMA) brushes having different lengths via a surface-induced atom transfer radical polymerization (SI-ATRP) method. FTIR-ATR and XPS tests of the formed polymer brushes indicate that these brushes have characteristic chemical structures of PHEMA; the polymer brush length revealed by the AFM tests increases linearly with reaction time. Cell lines of BMSCs, ATDC5, and human chondrocytes (HC) were cultured on these substrates to evaluate proliferation, adhesion, and differentiation. Our results demonstrated that the cells cultured on the substrates with short PHEMA brushes developed a spread morphology and organized actin fibers as compared to the cells cultured on those with long brushes. Different cell lines showed different responses depending on the PHEMA brush length. Cells cultured on long PHEMA brushes displayed a more rounded shape, higher gene expression of FAK and integrin, and lower gene expression of NCAM and N-cadherin as compared to those, especially ATDC5 cells, cultured on short PHEMA brushes. On PHEMA brushes with a long length, the cell lines express higher cartilage-specific genes including Sox9 and Col2 and GAG in ECM. The results suggest that polymer brushes having different lengths may interfere with the behavior of the cells cultured on them.
研究领域:
生物材料学
·
组织工程学
·
细胞生物学
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DOI
PubMed
高影响因子
MACROMOLECULES
·
2013
·
IF 5.521
Wei Sun,Shouxue Zhou,Bo You,Limin Wu
This paper is the first to present a facile method of fabricating intelligent surfaces with reversible, precisely controllable, two-way responsive wettability. The ABC-type block copolymers of tert-butyl methacrylate (tBMA), 2-hydroxyethyl methacrylate (HEMA), and 2-(diisopropylamino)ethyl methacrylate (DPAEMA) were synthesized through living radical polymerization mediated by a reversible addition–fragmentation chain transfer (RAFT) process and then grafted onto acyl chloride group-functionalized SiO2 films to produce V-shaped PDPAEMA-b-PHEMA-b-PtBMA brush-grafted SiO2 films. After hydrolysis, V-shaped polymer brushes with two arms of PDPAEMA and PMAA were produced. Because the PMAA and PDPAEMA segments were highly and independently responsive to pH values, the as-obtained films not only exhibited reversible, one-to-one, precisely controllable wettability but also two-way response behavior as pH value increased.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
MACROMOLECULES
·
2023
·
IF 5.5
Yanqiu Du,Yunhan Zhang,Jing Jin,Shiyan Xiao,Haojun Liang,Wei Jiang
The robustness and stability of self-assembled colloidal suprastructures are pivotal and challenging in the field of soft condensed matter and nanotechnology. Herein, we develop a novel approach to “self-locking” the colloidal suprastructures to achieve excellent stability by taking advantage of the topology of polymer brushes on nanoparticles. Compared to linear polymer brushes, looped polymer brushes can significantly improve the structural stability of the suprastructures. A combination of experiments and simulations reveals that the suprastructures achieve their significant stabilities through a “self-locking” mechanism by forming folded entanglement between looped polymer molecules. The stabilized suprastructures can stay intact in various organic solvent environments or under heating and mechanical oscillations. Furthermore, the interparticle spacing of suprastructures can be modulated by controlling polymer conformations in an aqueous solution through varying salt concentrations. This new approach of “self-locking” provides an easy-to-operate strategy to stabilize suprastructures and modulate interparticle distances without adding chemicals, which allows the potentially wide applications of colloidal suprastructures under harsh environments.
研究领域:
软物质物理
·
纳米技术
·
材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 32
·16769-16776
·
IF 3.708
Mingyuan Zhu,Guangqin Luo,Lihua Kang,Bin Dai
In the study, an HPW–PDMAEMA–SiO2 (phosphotungstic acid (HPW); poly-N,N-dimethylaminoethyl methacrylate (PDMAEAM)) catalyst was successfully synthesized. The synthesized HPW–PDMAEMA–SiO2 catalyst was characterized via XRD, TEM, FT-IR, TGA, and ICP-AES. The results show that the HPW active species retained its Keggin structure after immobilizing into polymer brushes. At optimal reaction conditions, the oxidative desulfurization conversion of dibenzothiophene reached 100%, and there was no significant catalytic performance decrease after six recycles. The excellent recoverability of the catalyst was attributed to the decreased leaching of the HPW active species caused by the strong interaction between the negative [PW12O40]3− ions and positive ammonium ions in the PDMAEMA polymer brushes.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Run Zou,Jun Xu,Sebastian Kuffner,Julian Becker,Tao Li,Xiang Guan,Xiaowan Zhang,Li Li,Martien A. Cohen Stuart,Xuhong Guo
Catalytic aquathermolysis in situ upgrading and reducing the viscosity of heavy oil in the reservoir remarkably enhances the recovery and is considered as a promising technology. However, the low catalytic efficiency and inferior dispersity in both water and oil limit its applications. In the present work, spherical polymer brush nanocatalysts were synthesized, in which nano-TiO2 is the core and poly(vinyl imidazole) (PVI)-loading nickel cations are polymer brushes. The chemical characteristics, polymer-grafting content, nickel-loading content, and morphology of as-prepared catalysts were characterized by infrared (IR) spectroscopy, thermogravimetric analysis, inductively coupled plasma optical emission spectrometry, scanning electron microscopy, and transmission electron microscopy. The polymerization degree of PVI was analyzed by proton nuclear magnetic resonance (1H NMR) spectra. The effects of the nickel-loading content, catalytic conditions, and hydrogen donor on the viscosity of heavy oil were studied. The results show that the heavy oil is catalytically cracked by the synthesized catalysts, which leads to the reduction of oil viscosity. The viscosity reduction is enhanced by the increase of the nickel-loading content, catalytic temperature, dosage of catalyst, and hydrogen donor. The rheological behaviors in terms of flow curve, thixotropy, viscoelasticity, and time dependence of cracked oil were studied. To explore the cracking mechanism, the four compositions of heavy oil before and after aquathermolysis were compared. The extracted asphaltenes and resins were further analyzed by elemental analysis, 1H NMR spectra, and IR spectroscopy. The organic compounds in reacted water were characterized by gas chromatography–mass spectrometry. It is found that the content of light saturates is much increased after aquathermolysis, along with the distinct decrease of resins. From the structure change of resins, such as the decrease of hydrogen/carbon and methylene/methyl ratios and increase of aromaticity and aromaticity condensation, the increased light saturates are due to the dissociation of alkyl side chains in resins. In addition, the aromaticity and aromaticity condensation in asphaltenes are found decreased, which is because of the fragmentation and depolymerization of large aromatics. Meanwhile, the loss of oxygen in both asphaltenes and resins is connected with the phenols found in the reacted water, indicating the breakage of the C–O bond and heteroaromatic ring-open reaction in both asphaltenes and resins during aquathermolysis.
研究领域:
化学工程
·
材料科学
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产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 8
·1932
·
IF 5
Liang Yu,Ziwei Li,Chen Hua,Kaimin Chen,Xuhong Guo
Metal nanoparticles are widely used in catalysis. Loading metal nanoparticles into polymer brushes has aroused wide attention, but regulation of catalytic performance still needs to be improved. The novel diblock polymer brushes, polystyrene@sodium polystyrene sulfonate-b-poly (N-isopropylacrylamide) (PSV@PSS-b-PNIPA) and PSV@PNIPA-b-PSS with reversed block sequence, were prepared by surface initiated photoiniferter-mediated polymerization (SI-PIMP) and used as nanoreactors to load silver nanoparticles (AgNPs). The block sequence caused the difference of conformation and further affected the catalytic performance. PSV@PNIPA-b-PSS@Ag was found to be able to control the amount of AgNPs exposed to external reactant of 4-nitrophenol at different temperatures to achieve regulation of the reaction rate due to the hydrogen bonds and further physical crosslinking between PNIPA and PSS.Keywords:diblock polymer brush;temperature response;hydrogen bond;silver catalyst
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Siwei Chen,Qingqing Chen,Baogang Wang,Hongsheng Lu
The application of carbon dots (CDs) as lubricant additives of nonpolar oils such as poly-α-olefins (PAOs) has been greatly hindered because most of CDs derived from the bottom-up method were water-soluble. In this work, the oil-soluble polymer brushes grafted CDs were synthesized by the surface-initiated atom transfer radical polymerization of bis-alkyl chain monomers. As expected, the polymer grafted CDs exhibited the excellent long-term dispersion stability in PAO owing to the principle of similar compatibility. As the lubricant additives of PAO4, the CDs showed the best friction-reducing and anti-wear properties when the polymerization time was 2 h. Adding 1 wt% of CDs could make the coefficient of friction and wear volume of PAO4 reduce by 64.1 % and 49.6 %, respectively. Moreover, both the tribological properties and anti-rust performance of CDs were superior to the commercially used ZDDP. The distinguished friction-reducing and anti-wear properties of CDs were attributed to the synergistic lubrication of carbon cores and polymer brushes. The rolling, repairing and polishing action of carbon cores, together with the tribo-reactions of polymer brushes, resulted in the formation of tough lubricating films on the rubbing surfaces, thereby tremendously alleviating the friction and wear of tribopair. The impressive anti-rust performance of CDs could be assigned to their strong adsorption ability on metallic surfaces. The above results are hopeful to provide useful information for the design and development of efficient multifunctional additives such as polymer-grafted metallic or inorganic nanomaterials.
研究领域:
材料科学
·
润滑工程
·
表面化学
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产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2018
·
IF 5.738
Wangmeng Hou,Lin Wei,Li Liu,Hanying Zhao
Well-defined polymer–protein bioconjugates are widely used in therapeutics and biocatalysis. One of the challenges in the synthesis of bioconjugates is the efficient separation of the target conjugate molecules from reaction systems. In this research, surface coassembly of polymer brushes and polymer–protein bioconjugates is investigated, and it is demonstrated that the coassembly approach can be applied in the purification of polymer–protein bioconjugates. Bovine serum albumin-poly(N-isopropylacrylamide) (BSA-PNIPAM) bioconjugates were synthesized by the “grafting from” approach, and PNIPAM brushes on silica particles were prepared by the “grafting to” approach. PNIPAM brushes on silica particles are able to coassemble with BSA-PNIPAM at a temperature above the lower critical solution temperature of PNIPAM. Two-layer surface structures with collapsed PNIPAM in the inner layers and BSA in the outer layers are formed on the silica particles. The size of the silica particles and molecular weight of PNIPAM on the bioconjugates exert influences on the coassembly. The coassembly approach can be used in the purification of bioconjugates. After repeated coassembly centrifugation-release cycles, all the BSA-PNIPAM bioconjugates can be removed from the reaction solutions, and the purified bioconjugates are obtained.
研究领域:
材料科学
·
生物化学
·
分子生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）