CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Yu Dai,Chenbo Meng,Hang Wu,Longbo Luo,Xiangyang Liu
Electrical insulation materials with excellent thermal resistance and high breakdown strength have great application potential in energy storage devices. Herein, poly(benzimidazole-terephthalamide) (PABI) film with ultra-high breakdown strength was prepared by introducing three-dimensional covalent crosslinked structure, which was constructed by reactive PABI oligomers (PABI-O) and nano-SiO 2 derivate (SiO 2 -Ac). PABI-O was end-capped with acryloyl chloride, and crosslinking reaction of C C groups from acryloyl chloride could take place above 300 °C. Then, SiO 2 -Ac grafted with large amounts of C C groups on its surface was prepared, and it was blended with PABI-O, which was followed by processing into films and annealing at 360 °C. Due to steric structure of SiO 2 -Ac and large amounts of C C groups on its surface, three-dimensional crosslinking can be attained in the composite film by radical addition reaction of SiO 2 -Ac and PABI-O. It is found that the three-dimensional crosslinked structure can increase path tortuosity in the electrical treeing breakdown, which endows the film with breakdown strength up to 624 kV mm −1 and shows 70% enhancement compared with that of Kapton film (a famous polyimide film). Moreover, the film exhibits excellent mechanical properties and dimensional stability. Tensile strength of the film is nearly 340 MPa, and the coefficient of thermal expansion (CTE) is only 5.06 ppm/°C at 20–250 °C.
研究领域:
材料科学
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电气工程
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2023
·
IF 5.2
Lipei Fu,Ziran Zhang,Xinxin Qiu,Yufei Zheng,Minglu Shao,Yingrui Bai,Zhangkun Ren,Wenzhe Si,Jiafeng Jin,Yanyu Xu,Kaili Liao
A novel rapidly switchable CO 2 /N 2 -responsive Pickering emulsifier based on supramolecular amphiphilic surfactants (SDOA) and nano-SiO 2 has been fabricated. SDOA was constructed by mixing Jeffamine D-230 and oleic acid (HOA) at 1:1 stoichiometric ratio. Compared with conventional small-molecule emulsifiers, the novel rapidly switchable CO 2 /N 2 -responsive Pickering emulsifier was prepared with inexpensive raw materials by a simple method, and there was no contaminant generation during synthesis. A new CO 2 /N 2 -responsive Pickering emulsion was prepared on this basis, and its stable performance and responsiveness were investigated in depth. The results show that this emulsion can be stable for a long time (more than 30 days) at a low surfactant dosage (0.5 mmol/L) through in situ hydrophobization of SiO 2 nanoparticles by hydrogen bonding and electrostatic adsorption. In addition, the emulsion broke rapidly and completely after 10 s of CO 2 introduction into the stable emulsion, and the emulsion could be reconstructed in response to N 2 purging for 5 min at 60 ℃ followed by homogenization . The switching behavior of the emulsion is due to decomposition of the pseudo amphiphile by bubbling CO 2 into the system and both the protonated D-230 ions and the neutral HOA produced have no in situ hydrophobization to SiO 2 particles. At 60 ℃, the influx of N 2 will drive out CO 2 , making HOA re-transform into hydroxide ion, and after re-combining with D-230 ion, it can again perform in-situ hydrophobization on SiO 2 particles, thus forming a stable emulsion. Thanks to the ability of SiO 2 nanoparticles and D-230 ions to maintain electrostatic adsorption after the passage of CO 2 , compared with previous studies, the emulsion can be completely demulsified at a higher pH value (about 5.5), fewer bicarcarbonate roots are formed, less CO 2 needs to be introduced, and N 2 required to re-stabilize the emulsion is also reduced. This greatly increases the response efficiency of the emulsion and reduces the energy loss and the cost of putting the emulsion system into practical application. This research has important implications for fossil fuel generation, production and transportation of crude oil, and other areas.
研究领域:
化学工程
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材料科学
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界面科学
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产品关联
DOI
高影响因子
Geoenergy Science and Engineering
·
2023
·
IF 0
Nanjun Lai,Wei Fan,Xiaochen Zhang,Liang Liu,Xuefeng Zhou,Siqi Chen
Shale instability caused by the development of nano-micron-scale fractures, pores, and bedding is always a challenge for drilling complex formations. In this work, two additives (Temperature-sensitive polymer based nano-SiO 2 composite (SNAS) and poly (NVP-TAAC-AMPS) (NTA)) were synthesized. The lower critical solution temperature (LCST) value of SNAS could be controlled by adjusting the monomer ratio. As temperature-sensitive nanocomposites , SNAS has the rheological control of drilling fluid. The effects of SNAS and NTA on shale stability were tested based on analytical approaches, including shale wettability , microporous membrane fluid loss, pressure transmission rate, shale specific surface area, shale pore volume, shale strength, linear swelling percentage and shale cuttings recovery. When the temperature is higher than the LCST value, due to the transition from hydrophilicity to hydrophobicity of SNAS, it not only changes the wetting angle of shale, but also enhances the plugging effect of SNAS. The composite system could form tight plugging layer and hydrophobic region compared with single SNAS, which was more conducive to improve plugging performance of shale. Finally, the synergistic improvement mechanism of shale stability combined with SNAS and NTA were further proposed.
研究领域:
石油工程
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材料科学
✓ 已验证
DOI
FIRE TECHNOLOGY
·
2024
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IF 2.3
Zhang Jiaqing,Shang Fengju,Liu Xin,Li Kaiyuan,Yang Yunpeng,Zou Yanyan
Nano SiO 2 particles (NPs) combined with organosilane surfactants present a promising avenue for the development of stable fluorine-free firefighting foams. In this study, hydrophilic nano SiO 2 particles, non-ionic organosilane surfactant (SiCare2238), and amphoteric hydrocarbon surfactant (LAMC) were prepared as a mixed dispersion to investigate the interactions between nano particles and surfactants, foaming ability, and foam stability of the mixed dispersion. Results indicated that the surface activity, electrical conductivity, and foaming ability of the mixed dispersion decreased with increasing NPs concentration. The impact of NPs on foam stability depended on the filling and blocking mechanisms within the platform boundary of the formed liquid film. At NPs concentrations below 1.5%, strong electrostatic interactions among surfactant molecules resulted in the adsorption of surfactant molecules on the nano particle surface, preventing the formation of a network structure at the platform boundary, thereby reducing foam stability. At NPs concentrations above 1.5%, a significant number of NPs formed a network structure, filling and blocking the platform boundary, leading to delayed foam drainage, coarsening, and enhanced foam stability. This study provides theoretical guidance for the application of nano particles in fluorine-free.
研究领域:
材料科学
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化学工程
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消防技术
✓ 已验证
DOI
高影响因子
Sustainability
·
2025
·Vol. 17
·期 15
·6987
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IF 3.3
Songling Chen,Fuxin Liu,Wenying Zhao,Jianrong Zhao,Xinlin Li,Jianfei Wang
Environmentally friendly coated urea prepared using a waterborne polymer coating material is essential for promoting green and sustainable practices in modern agriculture. However, significant efforts are still urgently needed to address the undesirable properties of waterborne polymer coatings, i.e., poor hydrophobic properties and numerous micropores. Herein, dual nano-SiO2and siloxane-modified waterborne-polymer-coated urea was successfully developed. The characteristics of waterborne-polymer-coated urea before and after modification were compared. The results demonstrate that nano-SiO2and siloxane modification improved the hydrophobicity (water absorption decreased from 119.86% to 46.35%) and mechanical strength (tensile strength increased from 21.09 to 31.29 MPa, and the elongation at break exhibited an increase of 22.42%) of the waterborne polymer coatings. Furthermore, the –OH number of the modified coatings was decreased, while the coating surface formed a nano-scale rough structure, prolonging the nitrogen (N)-controlled release period from 7 to 28 days. Overall, the proposed novel dual-modification technique utilizing waterborne polymer coatings highlights the significant potential of eco-friendly coated urea with renewable coatings in modern agriculture.
研究领域:
农业化学
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材料科学
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环境科学
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高分子科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Bionic Engineering
·
2020
·Vol. 17
·期 6
·1196-1208
·
IF 2.222
Yang Xiaona,Tian Limei,Wang Wei,Fan Yong,Sun Jiyu,Zhao Jie,Ren Luquan
The past decade has witnessed significant efforts in addressing the global metallic corrosion challenge, with a focus on avoiding or mitigating huge economic losses incurred by corrosion and on the development of protective coatings on metals. Herein, a synergistic anticorrosion coating with both superhydrophobicity and self-healing properties was reported, through a facile replica molding method by mixing the polyvinylidene fluoride (PVDF) matrix with nano-sized SiO 2 particles and 2-mercaptobenzothiazole (MBT) loaded halloysites (HNTs). The surface exhibits robust self-cleaning behavior under harsh conditions and high liquid repellence to withstand the osmosis of corrosive ions. The self-healing performance of the coating, due to the introduction of MBT-loaded HNTs, enhances the anticorrosion capability, which is still valid once the protective layer is damaged. Potentiodynamic polarization (PDP) and Electrochemical Impedance Spectroscopy (EIS) measurements demonstrate that the synergetic effects in anticorrosion performances significantly enhance the long-term corrosion protection of metals. Hence, this type of dual-action coating may find unique applications in metal corrosion resistance where both super-repellency and self-healing properties are desired.
研究领域:
材料科学
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腐蚀与防护
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER INTERNATIONAL
·
2018
·Vol. 68
·期 4
·675-683
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IF 2.352
Bing Yang,Yu Zhou,Wenjie Yu,Song Zhang,Hongxiang Chen,Ju Ye
In order to improve the dispersity and stability of the nano-SiO 2 aqueous system with high solid content, a kind of polyacrylic acid dispersant with methoxysilicon end groups (KH590-PAA) was synthesized by photopolymerization of acrylic acid (AA) initiated with (3-mercaptopropyl)trimethoxysilane (KH590). After adding KH590-PAA into the nano-SiO 2 aqueous dispersion system (20 wt% solid content), the viscosity and the curing time of the system were measured with a rotational viscometer and the inverted bottle method. Moreover, the dispersion mechanism of KH590-PAA for the nano-SiO 2 aqueous system was researched by measuring the adsorption capacity, the particle size and the zeta potential of the nanoparticles with a conductivity meter, dynamic light scattering, SEM and TEM, respectively. The results showed that the methoxysilicon groups in KH590-PAA could react with hydroxyl groups on the surface of nano-SiO 2 in the process of stirring, which enhanced the adsorption capacity of the dispersant and then increased the surface charge of the particles. Therefore, electrostatic repulsion and steric hindrance effects between the SiO 2 nanoparticles could be further enhanced by adding the KH590-PAA dispersant, and then the nano-SiO 2 aqueous system exhibited better dispersity and stability. Besides, the dispersion properties of SiO 2 nanoparticles in water were closely related to the addition amount and the molecular weight of the KH590-PAA dispersant. © 2018 Society of Chemical Industry
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
MATERIALS CHEMISTRY AND PHYSICS
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2022
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IF 4.778
Zhang Tianwei,Liu Hao,Zhiyue Han,Du Zhiming,Zhang Cunwei,Shan Liya,Wang Yong,Zhang Guiyun,Wang Gaofeng
The seawater dry water extinguishing materials formed by coating seawater with nano-SiO 2 have greatly enlarged the application space of the seawater as a fire-extinguishing medium. Against the deficiencies in the evaluation of the size-fractionated and stability of dry water extinguishing materials, especially of the coating effect of nano-SiO 2 , this study designed an airflow size-fractionated system applicable to dry water materials and characterized the stability of dry water materials by electrochemical methods according to the pneumatic separation principle. The results showed that the grain size range of seawater@nano-SiO 2 dry water extinguishing materials was 0.2–400 μm, and that the dry water could be divided into three intervals by granule size by adjusting the turbo-dynamo frequency and draught fan frequency of the airflow size-fractionated system. The electrochemical methods are applicable to describe the stability of the dry water extinguishing materials, and the gelatinization of core material can significantly make up for the deficiency that the core material of dry water tends to separate out over storage time. However, the stability of dry water is subject to granule size more than the gelatinization of the core material, and the dry water with big-size granules has optimal stability. Graded dry water is less corrosive to aluminum sheets, and the corrosion resistance to big-grained gel-dry water is optimal. The research conclusion can provide a technical basis for size-fractionated and covering effect characterization of dry water extinguishing materials and for type selection of storage media.
研究领域:
材料科学
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消防工程
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电化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
·
IF 8.1
Guangchao Li,Youbin Zheng,Hao Guo,Ze Li,Guohao Zhu,Liang Dong,Xin Liu,Jianbing Zang
In this paper, we present a method to enhance the stability of Fe–N–C electrocatalysts, known for their significant oxygen reduction reaction (ORR) activity and positioned as promising alternatives to commercial noble metal-based catalysts. Despite the favorable ORR activity, Fe–N–C suffers from inadequate stability in acidic media, primarily attributed the loss of active FeN 4 sites resulted from Fe-demetalation. However, recent investigation reveals that pyridine N exhibits remarkable stability in retaining Fe atoms. To address this, we achieved a high proportion of pyridine N doping in carbon nanofibers through a process involving nano-SiO 2 shell coating and electrospinning. The nano-SiO 2 shell coating method demonstrates efficacy and versatility in transforming pyrrole-type FeN 4 into pyridine-type FeN 4 , irrespective of the origin material being trivalent or divalent Fe, whether organic or inorganic.
研究领域:
电化学
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材料科学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2025
·
IF 4.7
Ousseini Seidina Ousseini,Bo Peng,Zhuang Miao,Kai Cheng,Mandella Ali,Jingwei Li,Jixiang He,Seybou Yacouba Zakariyaou
This study presents the synthesis and evaluation of a novel nanocomposite using dispersion polymerization of Acrylamide (AM), Acrylic Acid (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS), and N, N’-methylenebisacrylamide (MBA) grafted onto the surface of modified nano-SiO 2 (M-NS). The modification, achieved using γ-Methacryloyloxypropyltrimethoxysilane (KH570), enhances hydrophobicity and stability. Comprehensive characterization techniques, including ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared (FTIR), laser particle size analysis, and zeta potential measurements were employed to confirm the structural integrity and functionalization of the nanocomposite. Emphasis was placed on examining swelling, viscosity, and dispersion stability under various temperature, salinity, and water conditions to determine its effectiveness under high-temperature and high salinity environments typical of oil reservoirs. The results revealed significant enhancements in swelling behavior and dispersion stability, with high resistance to thermal degradation and salinity-induced aggregation. The nanocomposite demonstrates superior swelling behavior, viscosity retention, and thermal stability under high-temperature (70°C) and high-salinity (up to 20g/L NaCl) conditions, outperforming traditional grafted polymers. Results demonstrated that swelling ratios improve by 45% with 2wt% M-NS, and viscosity degradation is significantly reduced over 20 days of aging. Ionic effects, analyzed show enhanced resistance to divalent ions (Mg 2+ and Ca 2+ ), critical for harsh reservoirs environments. These findings suggest superior conformance control, compliance, and thermal stability, which were further improved with the rise of modified nano-SiO 2 positioning this nanocomposite as a promising option for chemical-enhanced oil recovery applications, addressing in permeability heterogeneity and salinity-induced aggregation.
研究领域:
材料科学
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石油工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Shuaiyan Ji,Wei Li,Ningning Lv,Xiaoting Chen
The superhydrophilic/underwater superhydrophobic membrane offers unique advantages in effectively separating oily wastewater. However, the development of membrane materials that can efficiently separate emulsions only under gravity is still a challenge. A crosslinked network copolymer P(MA-AMPS) was synthesized by radical polymerization of N, n-methylenebisacrylamide (MBA), methacrylamide (MA) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) initiated by potassium persulfate. Then polyvinyl alcohol (PVA) and nano-SiO 2 were inserted to the crosslinked polymer system in order to prepare a P(MA-AMPS)/PVA@SiO 2 hybrid hydrogel. The hybrid hydrogel can be sprayed on the surface of stainless steel mesh (SSM) by a simple spraying method, so as to achieve superhydrophilicity/underwater superoleophobicity. The oil-water emulsion permeation flux reached more than 352.94 L·m −2 ·h −1 , while xhibiting a more than 99.5 % separation efficiency under gravity. The anti-fouling tests demonstrated that the membrane exhibited outstanding anti-fouling performance. Moreover, the combination of stable semi-interpenetrating networks and nanoparticles made the membrane exhibit excellent stability and durable separation ability in complex physicochemical environments.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Na Li,Jie Zhu,Dongni Liu,Liu Liu,Chenggong Zhang,Dequn Wu
The flammability and bacterial susceptibility of cellulose have always posed significant safety hazards in its application. A multifunctional agent (SiCA) combining flame retardancy and antibacterial activity was developed using nano-hybridization in this study. The SiCA was centered around nano-SiO 2 , which was modified with a quaternary ammonium salt and a Schiff base. Through chemical grafting, SiCA was successfully immobilized on the cotton fabric surface. Flammability tests revealed that the limiting oxygen index (LOI) value of treated cotton fabric rose significantly from 18 % to 27.5 %. The modified fabric showed a 35.5 % reduction in peak heat release rate (pHRR) and achieved self-extinguishing behavior in UL-94 vertical flame tests. The antibacterial efficacy of modified fabric against Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli ) was also validated, with inhibition rates reaching 99.6 %. Furthermore, the biocompatibility of modified fabrics was evaluated using MTS assays and animal wound model. L929 fibroblast cell tests confirmed low toxicity of SiCA. The wound healing rate of 97.3 % was achieved after 14 days in animal model, indicating the function of promoting healing. The excellent flame retardancy, antibacterial, and biocompatibility of modified cotton fabric suggested it was an ideal candidate in military combat training uniforms, infant and toddler clothing, automotive interiors, public transportation, and medical settings.
研究领域:
材料科学
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纳米技术
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高分子科学
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生物医学工程
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消防安全工程
✓ 已验证
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）