APPLIED CLAY SCIENCE
·
2024
·
IF 5.3
Lei Hao,Kaitong Fan,Chengcheng Zhang,Lei Wang,Hong Xu,Jinxiang Dong
As natural montmorillonite has a very high phase transition temperature, natural organophilic montmorillonite as a thickening agent has been used to prepare high temperature grease. The thickening property of organophilic montmorillonite is influenced by montmorillonite composition and nature of the organic compounds. In order to improve the thickening ability of organophilic montmorillonite to obtain a stable and excellent lubricating performance of montmorillonite grease, synthetic montmorillonite with the uniform composition is an effective solution. Organophilic montmorillonite as a thickener usually uses a single long-chain quaternary ammonium salt to modify montmorillonite, which limits to further improve thickening ability. To address these issues, a new modification strategy was applied by selecting a very short chain quaternary ammonium salts and a long chain quaternary ammonium salts to co-modify synthetic montmorillonite. Synthetic organophilic montmorillonite was obtained through the co-intercalation of tetramethylammonium chloride (TMAC) and octadecyl trimethyl ammonium chloride (OTAC). Due to the huge difference in alkyl chains between TMAC and OTAC, the specific surface area and the number of mesopores of organophilic montmorillonite increased significantly. Molecular dynamics simulation further proved that TMAC entered the interlayer space and caused changes in the arrangement of interlayer organics. The interlayer space, organic content, and specific surface area can be effectively controlled by adjusting the molar ratio of TMAC and OTAC. The results revealed that molar ratio of TMAC and OTAC 2:8 was optimal, and the thickening ability of organophilic montmorillonite was equivalent to 5 times that of only OTAC. Tribological tests showed the grease exhibited good anti-wear ability and stable friction reduction at 180 °C. Due to the convenience of the synthetic method used and its superior rheological and tribological performance, this study may provide new insights into colloid, interface chemistry, and materials science to prepare organophilic montmorillonite.
研究领域:
胶体化学
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材料科学
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界面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
·
2024
·
IF 3.8
Xue Mei,Pingping Jiang,Pingbo Zhang,Zhixuan Cui,Xiaoyuan Zhu,Shijun Chen,Xunxun Sheng,Jingang Gao,Hang Gao
To make the hydrotalcite uniformly dispersed in polyvinyl chloride (PVC) and enhance its thermal stability, cinnamate-intercalated calcium aluminum hydrotalcite (CaAl-cinnamate-LDHs) underwent organic modification with cetyltrimethylammonium bromide/sodium dodecyl sulfate/polyethylene glycol (CTAB/SDS/PEG). The structures of modified hydrotalcite were characterized using x-ray diffractometer, scanning electron microscope, particle size analysis, and water contact angle test. The thermal stability was assessed through thermal aging oven experiment, Congo Red experiment, and thermogravimetric experiment, revealing their exceptional performance. Simultaneously, the synergistic effect of PEG-LDHs with auxiliary thermal stabilizers was examined, with epoxy soybean oil proving to be the most effective, which made the PVC sample incompletely black within 120 min. Mechanical properties and dynamic thermomechanical analysis indicated that the overall mechanical characteristics of the PVC samples with modified hydrotalcite were significantly superior to the unmodified CaAl-cinnamate-LDHs. Additionally, the optical performance test demonstrated excellent transparency in the PEG-LDHs/PVC sample. Through analyzing the thermal stability mechanism, it was indicated that hydrotalcite effectively absorbed HCl. Furthermore, the combination of PEG-LDHs and ESO replaced unstable Cl atoms and reacted with conjugated double bonds, thereby reducing the aging and discoloration of PVC. Highlights The modified hydrotalcite preparation process was simple and easy to operate. The CTAB/SDS/PEG-LDHs/PVC samples exhibited excellent thermal stability. Mechanical properties of the PVC samples with modified hydrotalcite were significantly superior to the unmodified CaAl-cinnamate-LDHs.
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
DALTON TRANSACTIONS
·
2012
·Vol. 41
·期 17
·5334-5342
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IF 3.838
Yan Zhao,Bing Yan
Three kinds of rare earth hybrid materials with enhanced thermostability and photoluminescence properties have been prepared for the first time by using a functionalized GaN matrix as one of the building blocks. A number of silane coupling agents (isocyanate triethoxysilane (ICTES), 3-chloropropyl triethoxysilane (CPTES) and 3-aminopropyl triethoxysilane (APTES)) behave as the covalent linkages for modification by both hydroxylation of GaN and functionalized photoactive ligands (4-mercaptobenzoic acid (MBA), 4-hydroxybenzoic acid (HBA) and nitrobenzoyl chloride (NBC)), resulting in the precursors (MBA–ICTES–GaN, HBA–CPTES–GaN and NBC–APTES–GaN). Subsequently, multicomponent photofunctional rare earth hybrid materials with the three precursors and 1,10-phenanthroline (Phen) are assembled and characterized by their FTIR spectra, UV–vis diffuse reflectance spectra, XRD patterns, and photoluminescent behaviour (luminescence, lifetime, quantum efficiency, and energy transfer). These results reveal that the Eu3+ hybrids with the MBA–ICTES–GaN unit have a better luminescence intensity ratio, higher quantum efficiency and longer lifetime than those with the HBA–CPTES–GaN and NBC–APTES–GaN units. Meanwhile the hybrid Phen–Tb–HBA–CPTES–GaN possesses a stronger characteristic emission of Tb3+ ions than the other two hybrids (Phen–Tb–MBA–ICTES–GaN and Phen–Tb–NBC–APTES–GaN). Moreover, two-color-based hybrid materials are fabricated by combining different molar ratios of Eu3+ and Tb3+ in the same system (Phen–RE–MBA–ICTES–GaN) with emission at a wavelength of 331 nm (RE = Eu, Tb) and yellow luminescence can be achieved.
研究领域:
材料科学
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光学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
·
IF 2.5
Shengyuan Liang,Yeyun Meng
A modified amine chain segment was synthesized through a reaction between polyethylene glycol (PEG) and bisphenol A epoxy resin. Subsequently, organically modified montmorillonite (OMMT) was prepared via ammonium salt formation under acidic conditions. Using phase inversion technology, an epoxy resin/organic montmorillonite composite emulsion was successfully fabricated, employing a minimal amount of an epoxy emulsifier with OMMT as a co-emulsifier. Thermal curing of this emulsion yielded the final OMMT/epoxy resin composites. Structural characterization was performed using Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) to confirm the chemical composition of the synthesized amine. X-ray diffraction (XRD) analysis verified the successful intercalation and exfoliation of montmorillonite during organic modification. The emulsion system was further evaluated through dynamic light scattering (DLS) and zeta potential measurements, which demonstrated that OMMT incorporation significantly enhanced emulsion stability by optimizing particle size distribution and increasing surface charge density. Thermal analysis revealed notable improvements in the thermomechanical properties of the composites, confirming the reinforcing effect of OMMT within the epoxy matrix.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2020
·Vol. 12
·期 7
·1611
·
IF 3.426
Lijie Huang,Xiaoxue Han,Haobin Chen,Shuxiang An,Hanyu Zhao,Hao Xu,Chongxing Huang,Shuangfei Wang,Yang Liu
In this study, we investigated the barrier properties of a montmorillonite-reinforced biomass material, starch. Organically modified montmorillonite materials were prepared from natural montmorillonite by reacting it with dodecyl trimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium chloride or octadecyl trimethyl ammonium chloride under ultrasonic conditions. The composite starch films incorporated with these organically modified montmorillonite samples were characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy and X-ray diffraction. The results showed that the introduction of montmorillonite decreases the transmittance of the composite film by 10% in the visible region and significantly inhibits UV-light transmittance. The decomposition temperature of the composite film ranges from 200 to 500 °C, with a weight loss rate of 80%. The distance between the montmorillonite layers increases from 0.14 nm in the non-magnetized state to 1.49 nm after magnetization. The oxygen permeability of the starch film modified by organic montmorillonite (0.067 cm3/m2·d) is lower than that of the montmorillonite starch film without magnetization (0.097cm3/m2·d). The oxygen barrier capacity is close to zero. Particularly in the ordered magnetic montmorillonite starch composite film, the oxygen barrier ability is the best. Therefore, modified montmorillonite could serve as an excellent reinforcing agent for cassava starch films and effectively improve the oxygen barrier performance of the films.
研究领域:
材料科学
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食品科学
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环境科学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Zhenzhu Zhou,Zhihao Zhang,Junchao Huang,Yuhua Wang
Fire resistance of steel structures is crucial to building safety to maintain structural integrity and avoid secondary damage (building collapse), when facing fire hazards . High temperature in fire rapidly softens the steel structure which fails to afford the load bearing. Water-based intumescent coating is now one of the most prospective treatments as it is excellent fire resistant, environmentally friendly, and economically effective. However, the poor density and thermal stability of its char residue make it difficult to be competent in a real fire. In this work, an organic-modified glass fiber grafted with 10-(2, 5-dihydroxyphenyl)-10-hydro-9-oxa-10-phosphaphenanthrene-10-oxide and γ -(2, 3-epoxypropoxy) propyltrimethoxysilane (ODOPB@KH560@GF) was prepared as the filler for the intumescent fire resistance coating containing ammonium polyphosphate/melamine/pentaerythritol (APP/MEL/PER) and water-based acrylic latex. The ODOPB@KH560@GF was found to enhance the thermal stability of the char layer and decrease the peak heat release rate and total heat release by 60.5 % and 58.8 % in a dosage of 5 wt % (AL-4). Also, the fire resistance limit of the steel plate coated with AL-4 was twice as high as that of the unprotected steel plate and higher than that of the steel plate coated with a certain commercial coating, leading to further applications in the fire safety coating for steel structures.
研究领域:
材料科学
·
防火安全工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2021
·
IF 3.383
Guang Yang,Qingqing Hu,Wenhao Yang,Wangyi Zeng,Yanxin Jiang,Liang Chai,Longjiang Deng
Carbonyl ion (CI) based magnetic particles are widely applied magnetic material. However, they are active metal and easily reacted with corrosive matters. Exploration of methods and techniques to reduce their reaction activity under corrosive environment never ceases. Herein, organic polyolefin copolymer maleic anhydride grafted polypropylene (PP-g-mah) is adopted as protection layer to chemically bond with flake carbonyl iron (FCI) particles. The hydrophobic PP-g-mah anchored FCI particles effectively integrates the natural barrier effect of stable polyolefin layer for resisting corrosion such thermal oxidation , electrochemical reaction , and chemical corrosion. Meanwhile, the hydrophobic nature of the PP-g-mah modified FCI particles can be utilized as useful component for preparing superhydrophobic flexible surface. This work provides a novel example to chemically coupling stable water resisting polymeric materials on FCI particles in a controlled manner to enhance the FCI particles anticorrosion ability. With future work of optimizing the coating uniformity and wettability , this work also paves the way for future development of corrosion resistive FCI based composites.
研究领域:
材料科学
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表面化学
✓ 已验证
DOI
高影响因子
RSC Advances
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2016
·Vol. 6
·期 47
·41420-41427
·
IF 3.289
Guohui Li,Avinav G. Nandgaonkar,Keyu Lu,Wendy E. Krause,Lucian A. Lucia,Qufu Wei
The engineering of supports for enzyme immobilization while retaining competent functionality is nontrivial. We attempted to enhance the removal efficiency of organics by adopting a relatively novel approach involving a synergy from the adsorption capabilities of a support incorporated with organically modified montmorillonite (O-MMT) and catalytic properties of immobilized laccase. Electrospun polyacrylonitrile (PAN)/O-MMT membranes after alkaline hydrolysis and carboxyl activation were chosen as the support system for laccase immobilization. A confocal laser scanning microscope confirmed a uniform enzyme distribution along with the fibers' longitudinal surface. After enzyme immobilization, the optimum pH shifted from 3 to 3.5, while the optimum temperature remain unchanged at 50 °C. Its stability was preserved despite a large fluctuation in pH (50% of its initial activity retained over the pH range 2–6) and temperature (more than 80% of its initial activity retained over 30–70 °C). Compared to free laccase, the thermal stability of the immobilized laccase was improved after being under 30 °C and 50 °C for 8 h. The operational stability was 68% of the initial one after 10 times repeated usage, while also demonstrating 80% storage stability of the initial activity even after two months. The immobilized laccase showed a high removal efficiency of crystal violet at an optimum pH of 5 and temperature ∼40 °C as well as an initial substrate concentration of 100 mg L−1. Compared with that of the individual support and the free laccase, the removal efficiency by an immobilized enzyme is far higher to confirm a synergy in the immobilized enzyme and support system.
研究领域:
生物技术
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 3.6
Xiaoyang Jia,Ke He,Xingyu Liu,Zhuoran Yang,Rui Huang,Yangling Liu,Jun Lin,Xin Liu,Jian Wang,Shaojian He
For the proton exchange membrane (PEM) applying in vanadium flow battery (VFB), it is difficult to separate the electrolyte ions at two electrodes while conducting protons. In this work, a novel composite membrane is developed, organically modified-MXene (MDP) filled sulfonated poly(ether ether ketone) (SPEEK) membrane, where MDP is prepared through co-coating the polydopamine (PDA) and polyethyleneimine (PEI) on the surface of MXene. The two-dimensional structure of MXene can effectively reduce the vanadium ions permeation, while the surface functional groups from the coating layer can assist in proton transport, thus enhancing the membrane selectivity. The membrane with only 1.0 wt% MDP (SPEEK/MDP-1) achieves maximum selectivity of 7.1 × 10 7 S min cm −3 . Furthermore, the energy efficiency (EE) of the VFB loaded with SPEEK/MDP-1 reaches ~92.5% at 40 mA cm −2 current density. This work provides a new direction for enhancing the properties of PEM used in VFB applications. Graphical Enhanced EE of VFB by highly selective PEM.
研究领域:
电化学
·
能源材料
·
膜科学
·
储能技术
·
高分子材料
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Yongqian Shi,Bibo Wang,Lijin Duan,Yulu Zhu,Zhou Gui,Richard K. K. Yuen,Yuan Hu
Graphitic carbon nitride (g-C3N4) nanosheets are endowed with extraordinary chemical and thermal stability and good optical and photoelectrochemical properties and are expected to be used in a wide range of fields. The direct dispersion of hydrophobic g-C3N4 nanosheets in water or organic solvents without the assistance of dispersing agents is considered to be a great challenge. Here we report novel g-C3N4/organic-modified montmorillonite (OMMT) nanohybrids, which were synthesized through electrostatic interaction and then introduced into polystyrene (PS) matrix to fabricate nanocomposites by a simple solvent blending–precipitation method. Hybridizing g-C3N4 with OMMT could easily form stable aqueous colloids through electrostatic stabilization. These nanohybrids were evenly dispersed in PS and showed strong interfacial interactions with the polymer matrix. It is noted that the generation of total gaseous products was dramatically inhibited by combining g-C3N4 with OMMT. Moreover, flame retardancy was improved upon incorporation of the nanohybrids into PS host. These improvements were due to the strong interactions at interface of ternary systems, synergism between g-C3N4 and OMMT, and physical barrier effect of the two components. This work provides a new pathway to manufacture well-dispersed polymeric materials with enhanced fire safety.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Journal of Coatings Technology and Research
·
2016
·Vol. 14
·期 1
·107-115
·
IF 1.342
Wang Ying,Cao Zhichao,Liu Fengguo,Xue Xiangxin
Epoxy acrylate (EA) coatings modified with organically modified rectorite (OREC) were synthesized employing the ultraviolet-curing technique. Two kinds of alkyl ammonium ions, octadecyltrimethylammonium chloride (OTAC) and [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MAOTMA), were used to modify rectorite (REC). The methacrylate functionalities of MAOTMA were capable of reacting with the acrylate groups of EA. The structure of OREC was characterized by FTIR and XRD and the results indicated that the surfactants were successfully intercalated into the REC interlayers via cation exchange process. The morphology of nanocomposites was investigated by SEM and TEM. OREC showed better dispersion in EA matrix compared with unmodified REC. The T
g of neat EA obtained by DMA was 75.6°C, while for 5 wt% EA/MAOTMA-REC and EA/OTAC-REC nanocomposites it increased to 76.5 and 80.8°C, respectively. The nanocomposite with 3 wt% loading of OTAC-REC had the highest T
g (89.7°C). TGA revealed that the thermal stability of nanocomposites was enhanced by OTAC-REC and MAOTMA-REC and the thermal stability of EA/MAOTMA-REC nanocomposites was better than that of EA/OTAC-REC nanocomposites. The mechanical properties of nanocomposites containing OTAC-REC and MAOTMA-REC were better than those of nanocomposites containing unmodified REC. With increasing OREC content, the adhesive force of nanocomposites decreased slightly and the flexibility increased significantly.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2024
·
IF 3.2
Qiang Luo,Fei Li,Weijun Zhen,Qing Ge,Yushen Zhou,Chunmei Ma,Pengtao Sun,Jianbo Xu,Buning Chen
To improve the adsorption and reusability of polypropylene (PP) fiber membranes, the organically modified saponite (Sap@P(St-co-MMA)) was prepared by solution polymerization. Furthermore, PP-based nanocomposite fiber membranes with strong oil adsorption, thermal stability, and reusability were prepared via melt-blown technology. The increased specific surface area of PP-based nanocomposite fiber membranes (PP-1.5%) provided more active sites for the oil adsorption. Simultaneous rheology and Fourier transform infrared measurements tests showed that Sap@P(St-co-MMA) enhanced the crystallinity of PP matrix, promoted the regular arrangement of molecules, and improved the intermolecular interaction force, which was beneficial for the oil adsorption. The adsorption of PP-1.5% (1.5 wt% addition of Sap@P(St-co-MMA)) fiber membrane for xylene and kerosene reached a maximum of 15.84 and 22.84 g g −1 , respectively. In the treatment of coal tar wastewater, the removal rate of oil can reach 62.9%, and the removal rate can still reach 51.17% after five cycles of experiments. In summary, PP-1.5% fiber membrane does not produce secondary pollution to the environment, and is a kind of oil removal material with good application prospect. Highlights PP-based nanocomposites fiber membrane with strong oil adsorption was prepared. Organically modified saponite had strong heterogenous nucleation for PP matrix. Sap@P(St-co-MMA) increased the specific surface area of PP-based fiber membrane.
研究领域:
材料科学
·
环境工程
✓ 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）