Frontiers in Chemistry
·
2020
·
IF 3.693
Lai Nanjun,Zhu Qingru,Qiao Dongyu,Chen Ke,Tang Lei,Wang Dongdong,He Wei,Chen Yuemei,Yu Tong
To improve CO2 adsorption performance of nanoparticle absorbents, a novel tertiary amine functionalized nano–SiO2 (NS–NR2) was synthesized based on the 3–aminopropyltrimethoxysilane (KH540) modified nano–SiO2 (NS–NH2) via methylation. The chemical structure and performances of the NS–NR2 were characterized through a series of experiments, which revealed that NS–NR2 can react with CO2 in water and nanofluid with low viscosity revealed better CO2 capture. The CO2 capture mechanism of NS–NR2 was studied by kinetic models. From the correlation coefficient, the pseudo second order model was found to fit well with the experiment data. The influencing factors were investigated, including temperature, dispersants, and cycling numbers. Results has shown the additional surfactant to greatly promote the CO2 adsorption performance of NS–NR2 because of the better dispersity of nanoparticles. This work proved that NS–NR2 yields low viscosity, high capacity for CO2 capture, and good regenerability in water. NS–NR2 with high CO2 capture will play a role in storing CO2 to enhanced oil recovery in CO2 flooding.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 11
·7213-7225
·
IF 5.044
Zhang Jing,Bao Yan,Guo Mingyuan,Peng Zhenghua
Poor water solubility of cellulose acetate is a key factor limiting its application in leather finishing field. Herein, a self-emulsifying aqueous emulsion was synthesized by using cellulose diacetate (CDA) as the substrate, dimethylolbutyric acid (DMBA) as the hydrophilic agent, and hexamethylene diisocyanate (HDI) as the bridging agent. Because the flexible carbon chain of HDI has the advantages of easy bending and deformation, the problem of large steric hindrance and low reactivity of -OH during water-based CDA can be solved by using the method of converting reactive functional groups and transferring reactive sites. At the same time, the flexible molecule 1,4-butanediol (BDO) and propylene glycol polyether (N210) are used as chain extenders to increase the molecular stretch and curl ability by adjusting the ratio of molecular soft and hard segments, and improve emulsion stability and coating flexibility. And through the reaction of -NH 2 and -NCO on the surface of nano SiO 2 modified by KH550, the nano SiO 2 is evenly distributed in the CDA water-based polymer to improve the comprehensive performance of the emulsion coating. Thus the nano-SiO 2 modified cellulose acetate water-based polymer emulsion (SiO 2 /WCDA) is obtained for leather finishing. The emulsion particles show an oil-in-water (O/W) core–shell structure, and the average particle size and dispersion coefficient (PDI) of the particles are 88.79 nm and 0.150, respectively. The surface of the coating film is compact, flat, and hydrophobic, with the contact angle is 104.3 °. In addition, the coating film has good adhesion, water resistance, heat resistance, yellowing resistance, chemical resistance, flexibility and mechanical properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Gaopan Dong,Zhengqiu Yuan,Xiujuan Guo
Petroleum-based plastics are widely used because of their practicable properties and low cost. However, people are equally concerned about the environmental damage generated by non-biodegradable petrochemical plastics. In this study, pinewood was employed as the raw material to prepare cellulose acetate and further synthesize the degradable composite films, which showed potential feasibilities to substitute the traditional petroleum-based plastics. In order to improve the barrier performance, hydrophobic performance, and mechanical properties of the film materials , nano-SiO 2 was introduced as functional filler for experimental exploration. The tensile strength, light transmittance, water vapor transmittance, microstructure, and crystalline structure of the nano-SiO 2 /pinewood-derived cellulose acetate composite films were determined by mechanical analysis, optical analysis, SEM, XRD , FT-IR, and barrier characterization methods, respectively. The results exhibited that the prepared films with the inclusion of nano-SiO 2 did not conduct reduction in transparency due to its good dispersion in the composite film. The barrier property, hydrophobic performance, and mechanical properties of cellulose acetate composite film were effectively improved due to the interaction between nano-SiO 2 and cellulose acetate molecular chains by the hydrogen bonds formed between hydroxyl groups. It was confirmed that the nano-SiO 2 /pinewood-derived cellulose acetate composite films exhibit great application potential as an environmentally friendly and efficient material for packaging.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Ying Zhang,Hongsheng Lu,Baogang Wang,Na Wang,Dongfang Liu
A novel stimulus-responsive non-Pickering emulsion stabilized by nano-SiO2 particles was prepared in our recent study. 4-formylbenzoic acid and hexylamine through a dynamic covalent bond form a surface-active substance, which was confirmed by Fourier transform infrared (FTIR) and 1H NMR. Through optimization experiments, it was proved that a stable emulsion can be formed by low surfactant concentration (below cmc) and low nano-SiO2 particle concentration (0.5 wt %). In this emulsion, nano-SiO2 particles are not located at the interface of oil–water but dispersed in the continuous phase of the emulsion, which is different from the Pickering emulsion. The negatively charged nano-SiO2 particles and anionic surfactants repel each other, thereby synergistically stabilizing the emulsion so that the concentrations of surfactants and nanoparticles required to stabilize the emulsion are reduced. In addition, the system can also control the formation and fracture of dynamic covalent bonds by changing pH, thereby controlling the stability and demulsification of the emulsion. At the same time, this non-Pickering emulsion could be used as a microreactor for chemical synthesis and still had a high yield after three cycles. This study provides a new application direction for this environmentally friendly emulsion.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Haibo Ding,Haopeng Zhang,Qinshan Xie,Ali Rahman,Yanjun Qiu
Wax crystals may continuously precipitate from the asphalt binder during the cooling process, which seriously damages the low-temperature cracking resistance of the pavement. At present, few researchers have developed wax inhibitors (WIs) to hinder wax crystallization of the asphalt binders. In this paper, a novel wax Inhibitor was synthesized by the hybridization of organically modified Nano-SiO 2 to the poly (methyl methacrylate) (PMMA), and the modification effect was validated by the ninhydrin chromogenic method and thermogravimetric analysis . The optimum content and composition of the organic nano-SiO 2 hybrid PMMA WIs were also determined by the rheological tests, including viscosity measurement , wax precipitation temperature (WPT), and yield stress tests. Moreover, the wax inhibition mechanism was predicted by the combination of differential scanning calorimetry (DSC) and polarized optical microscopy (POM) tests. According to the obtained results, the successful modification of nano-SiO 2 and PMMA were represented by the blue-violet precipitation and improved high temperature stability of PMMA, respectively. The optimal content and composition of nano-SiO 2 hybrid PMMA was determined as 200 ppm and mass ratio of 1:4 (nano-SiO 2 to PMMA), respectively. Compared with the co-crystallization between PMMA and wax crystals, the introduction of nano-SiO 2 provided an additional and more stable heterogeneous nucleation template, which further reduced the size, and increased the dispersion of the wax crystals. Consequently, it is promising to develop the nanocomposites as WIs in the asphalt binder.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Chengmin Hou,Ze Fan,Jiaqi Yang
Most of the super hydrophobic cotton fabric surfaces changed the original properties of cotton fabric and cannot be continuously used for oil-water separation. In this paper, the fluorine-containing epoxy polymer P(GMA- r -DFMA) was reacted with KH550 modified nano-SiO 2 to obtain an organic-inorganic hybrid super hydrophobic solution. By dipping process, the super hydrophobic cotton fabric surface was obtained. P(GMA- r -DFMA) can reduce the surface energy of cotton fabric, and modified silica can improve the surface roughness of cotton fabric to achieve super hydrophobic effect. The optimum parameters (polymer concentration, soaking time, drying time and drying temperature) for constructing super hydrophobic cotton fabric surface were explored. The optimal parameters are polymer concentration 5 mg/mL, soaking time 5 h, drying time 4 h, and drying temperature 120 °C. Under the optimal conditions, the water contact angle of the modified cotton fabric surface is 162±3 o and the water rolling angle is 10±1 o . The study on surface self-cleaning property of modified cotton fabric shows that modified cotton fabric can be restored to clean state after being soiled by toner and washed by deionized water. When the oils were n -hexane, n -octane and trichloromethane, the oil-water separation efficiency of the modified cotton fabric could reach 98%, 98% and 96%, and the effect was stable. The surface of modified cotton fabric has obvious silver mirror phenomenon. The results of Scanning Electron Microscopy showed that the surface of cotton fabric was smooth before modification, but many small bumps and folds were added on the fabric surface after super hydrophobic modification, and the roughness became larger. The super hydrophobic coating is very thin and does not change the color, softness and other properties of the cotton fabric.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2014
·
IF 3.583
Chenghui Li,Xue Jiang,Xiandeng Hou
Nano-SiO 2 was immobilized on the inner wall of a dielectric barrier discharge (DBD) tube, and it was coupled to a conventional gas chromatographer to investigate its performance as a molecular emission spectrometric detector for the determination of five volatile aliphatic amines. A charge-coupled device (CCD) was applied to observe the nano-SiO 2 -enhanced molecular emission spectra. The characteristic molecular emission bands of volatile aliphatic amines at 326.5 nm, 336.0 nm and 388.3 nm can be clearly resolved from the background emission spectra of carrier gas argon. The emission band of CN at 388.3 nm was used for quantitative detection of volatile aliphatic amines due to its high sensitivity. Nanomaterial catalysts including TiO 2 , MnO 2 , SiO 2 and ZnO were tested to enhance the emission signal of amines, and SiO 2 shows the best performance. The factors that influence the emission signal, such as discharge voltage, inner electrode length and carrier gas flow rate , were investigated in detail. The analytical performance of this method was evaluated by separation and detection of the mixture of five volatile aliphatic amines. Under the optimal experimental conditions, the limits of detection were found to be 4.4, 2.5, 2.2, 1.8 and 2.4 μg for dimethylamine , trimethylamine , n-butylamine, cyclohexylamine and ethylenediamine , respectively. This GC detector is not only sensitive but also fast in response to volatile aliphatic amines with good stability. Trimethylamine in a carp fish sample was monitored with storage time by the proposed method.
研究领域:
分析化学
·
材料科学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Xuechen Tang,Bobo Zhou,Chao Chen,Bauyrzhan Sarsenbekuly,Hongbin Yang,Wanli Kang
Due to the superior performance caused by surface modification and combined effects, polymer/nano-SiO 2 composites have been studied systematically for a long term and attracted increasing academic and industrial interests, especially in the petroleum engineering field. However, few works have been done on the mechanism that how the functional modification degree ( MD ) of nano-SiO 2 influences on the properties of the composites. In this work, a series of 3-(methacrylyloxy)propyltrimethoxysilane (MPS) modified nano-SiO 2 particles with different MD s were prepared and found to differ largely from each other in macroscopic properties . Then the effects of SiO 2 MD on the physicochemical property and the enhanced oil recovery (EOR) capacity of the corresponding polymer/nano-SiO 2 composite microspheres (PNSCMs) for the conformance control in oilfields were investigated in detail. The results clarified that by regulating the MD of nano-SiO 2 encapsulated in PNSCMs, the swelling property, viscoelasticity , mechanical strength and dispersion stability were significantly improved. Compared with traditional chemical copolymer microspheres CPMs, PNSCMs exhibited better conformance control and EOR ability, which was further improved as SiO 2 MD increased. The maximum oil recoveries of cores treated by PNSCMs were 76.14% and 52.45% in the experiment, and the EOR increased by 5.99% and 4.99% than those treated by CPMs, respectively, under homogeneous and heterogeneous conditions.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 34
·27097-27106
·
IF 3.84
Guiying Wu,Xin He,Li Xu,Houjin Zhang,Yunjun Yan
Novel Sapium sebiferum oil-based polyurethane (PU) nanocomposites with different contents of nano-SiO2 were successfully synthesized via an in situ polymerization method. Firstly, Sapium sebiferum polyol (SSP) was prepared in a continuous two-step process of epoxidation and hydroxylation, and nano-SiO2 particles were modified with 3-aminopropyltriethoxysilane (AMEO). Furthermore, SSP and isophorone diisocyanate (IPDI) reacted with a certain amount of the modified nano-SiO2 to enhance the physical properties of PU nanocomposites. The characterization of the structure and the properties of the surface modified nano-SiO2 and the PU/SiO2 nanocomposites were analyzed by Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), solid-state 29Si nuclear magnetic resonance (NMR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The results demonstrate that nano-SiO2 particles can be homogeneously dispersed in the PU matrix with a loading amount less than 5 wt%. Compared with the pure PU, the glass transition temperatures and initial decomposition temperatures of the PU/SiO2 nanocomposites were respectively enhanced by 20.5 °C and 43.5 °C with 3 wt% nano-SiO2 content. Moreover, the tensile strength of the PU/SiO2 nanocomposites was improved at 170%, and the water and toluene resistance properties of PU/SiO2 were also significantly enhanced.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Polymers
·
2022
·Vol. 15
·期 1
·186
·
IF 4.967
Qun Yang,Run Zhang,Mingfei Liu,Ping Xue,Lichao Liu
Ultra-high molecular weight polyethylene (UHMWPE)/high-density polyethylene (HDPE) blend with lower viscosity is more suitable for melt spinning compared to pure UHMWPE; however, the mechanical property of the blend fiber is hard to dramatically improve (the maximum tensile strength of 998.27 MPa). Herein, different content modified-nano-SiO2is incorporated to UHMWPE/HDPE blend fiber. After adding 0.5 wt% nano-SiO2, the tensile strength and initial modulus of UHMWPE/HDPE/nano-SiO2fiber are increased to 1211 MPa and 12.81 GPa, respectively, 21.57% and 43.32% higher than that of UHMWPE/HDPE fiber. Meanwhile, the influence of the nano-SiO2content on the performance for as-spun filament and fiber are emphatically analyzed. The crystallinity and molecular chain orientation of as-spun filament reduces with the addition of nano-SiO2. On the contrary, for fiber, the addition of nano-SiO2promoted the crystallinity, molecular chain orientation and grain refinement more obvious at a lower content. Furthermore, the possible action mechanism of nano-SiO2in the as-spun filament extrusion and fiber hot drawing stage is explained.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2022
·
IF 7.693
Kailun Xia,Yue Gu,Linhua Jiang,Kai Lyu,Mingzhi Guo,Weizhun Jin
In surface treatment technics of cement-based materials, nanoSiO 2 (NS) is effective in refining pore structure while organic water-repelling agents are often used for producing a hydrophobic surface. Due to its advantages of pore refining effect and hydrophobicity, the organic-inorganic hybrid nanoSiO 2 has attracted increasing attention. However, the UV-irradiation can result in photodegradation of organic constituents, leading to deterioration of hydrophobicity. In this study, a novel UV-resistant fluorinated hybrid nanocomposite, NS@TOFS, was synthesized and used for surface treatment on hardened cement-based materials. The water and gas permeability of the treated samples before and after UV-aging were assessed by measuring the water absorption rate, water contact angle and carbonation degree. The experimental results showed that the NS@TOFS treated samples possess enhanced water and gas impermeability after 14 days of exposure to UV rays. A morphological observation of the treated surface revealed that a synergistic effect of organic film and refined pore structure was responsible for the improved surface properties. Findings from this study well demonstrate that the developed fluorinated hybrid nanoSiO 2 holds great promise for enhancing the durability of cement-based materials under UV-irradiations.
研究领域:
建筑材料学
·
表面处理技术
·
纳米材料科学
✓ 已验证
DOI
高影响因子
Green Processing and Synthesis
·
2019
·Vol. 8
·期 1
·667-676
·
IF 1.128
Dan Chen,Binglin Li,Bin Li,Xiaoli Zhang,Longhui Wei,Wenwen Zheng
Catalytic efficiency in synthesis of vitamin E succinate was dramatically increased via the preparation of robust catalyst and the improvement of reaction system. 4-dimethylaminopyridine (DMAP) was covalently immobilized on nano-SiO 2 to avoid the catalyst contamination of the product and permit the easy recycling of DMAP. Then, a hexane-acetone mixed solvent system was firstly introduced to replace the traditional single-solvent system, which was employed to improve the activity of immobilized DMAP derivative and the substrate solubility of the reaction system. The highest vitamin E succinate yield of 94% was achieved. In addition, the recyclability and stability of the immobilized DMAP derivative was excellent, the yield of vitamin E succinate had no obvious loss and remained 90% after recycling 20 times. The excellent results make this technology be a promising candidate for the industrial production of vitamin E succinate.
研究领域:
生物化学
·
制药工程
✓ 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）