Articles de revues : « Aerosol polymerization »

1

Davis, E. James, et Mark F. Buehler. « Chemical Reactions with Single Microparticles ». MRS Bulletin 15, n^o 1 (janvier 1990) : 26–33. http://dx.doi.org/10.1557/s088376940006070x.

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Fine particles can be produced via aerosol processes either by means of vapor phase reactions that produce solid or liquid particles or by reactions between a preexisting solid or liquid particle and a reactive gas. This article examines the latter processes because a strong interest has developed in the production of materials via aerosol processing. Although fine particles are frequently produced using flow systems, such as in the laminar flow aerosol reactor of McRae and his co-workers, fundamental studies of the chemical kinetics are more readily done using single microparticles or microdroplets. Design of an aerosol reactor requires knowledge of the reaction rates, for there must be a sufficient residence time of the reacting species in the reactor to complete the desired reaction.Matijević reviewed early work on preparing well-defined and very pure metal oxides by hydrolysis of alkoxide aerosol particles, and Ingebrethsen and co-workers studied the hydrolysis rates of aerosol droplets of aluminum and titanium alkoxides and mixtures of the two alkoxides. Following Matijevic and his colleagues, Okuyama et al. used the thermal decomposition of metal alkoxide vapors to produce ultrafine particles of the oxides of titanium, silicon, and aluminum. The preparation of polymeric aerosols has been studied by Partch et al. and by Ward et al. The latter investigators used single-particle techniques (the electrodynamic balance) to obtain polymerization rate data for the photochemical polymerization of acrylamide monomer microparticles.

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Ward, Timothy L., S. H. Zhang, Theresa Allen et E. James Davis. « Photochemical polymerization of acrylamide aerosol particles ». Journal of Colloid and Interface Science 118, n^o 2 (août 1987) : 343–55. http://dx.doi.org/10.1016/0021-9797(87)90469-3.

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Liggio, J., et S. M. Li. « Reversible and irreversible processing of biogenic olefins on acidic aerosols ». Atmospheric Chemistry and Physics 8, n^o 7 (9 avril 2008) : 2039–55. http://dx.doi.org/10.5194/acp-8-2039-2008.

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Abstract. Recent evidence has suggested that heterogeneous chemistry of oxygenated hydrocarbons, primarily carbonyls, plays a role in the formation of secondary organic aerosol (SOA); however, evidence is emerging that direct uptake of alkenes on acidic aerosols does occur and can contribute to SOA formation. In the present study, significant uptake of monoterpenes, oxygenated monoterpenes and sesquiterpenes to acidic sulfate aerosols is found under various conditions in a reaction chamber. Proton transfer mass spectrometry is used to quantify the organic gases, while an aerosol mass spectrometer is used to quantify the organic mass uptake and obtain structural information for heterogeneous products. Aerosol mass spectra are consistent with several mechanisms including acid catalyzed olefin hydration, cationic polymerization and organic ether formation, while measurable decreases in the sulfate mass on a per particle basis suggest that the formation of organosulfate compounds is also likely. A portion of the heterogeneous reactions appears to be reversible, consistent with reversible olefin hydration reactions. A slow increase in the organic mass after a fast initial uptake is attributed to irreversible reactions, consistent with polymerization and organosulfate formation. Uptake coefficients (γ) were estimated for a fast initial uptake governed by the mass accommodation coefficient (α) and ranged from 1×10-6-2.5×10-2. Uptake coefficients for a subsequent slower reactive uptake ranged from 1×10-7-1×10-4. These processes may potentially lead to a considerable amount of SOA from the various biogenic hydrocarbons under acidic conditions, which can be highly significant for freshly nucleated aerosols, particularly given the large array of atmospheric olefins.

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Liggio, J., et S. M. Li. « Reversible and irreversible processing of biogenic olefins on acidic aerosols ». Atmospheric Chemistry and Physics Discussions 7, n^o 4 (14 août 2007) : 11973–2009. http://dx.doi.org/10.5194/acpd-7-11973-2007.

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Abstract. Recent evidence has suggested that heterogeneous chemistry of oxygenated hydrocarbons, primarily carbonyls, plays a role in the formation of secondary organic aerosol (SOA); however, evidence is emerging that direct uptake of alkenes on acidic aerosols does occur and can contribute to SOA formation. In the present study, significant uptake of monoterpenes, oxygenated monoterpenes and sesquiterpenes to acidic sulfate aerosols is found under various conditions in a reaction chamber. Proton transfer mass spectrometry is used to quantify the organic gases, while an aerosol mass spectrometer is used to quantify the organic mass uptake and obtain structural information for heterogeneous products. Aerosol mass spectra are consistent with several mechanisms including acid catalyzed olefin hydration, cationic polymerization and organic ester formation, while measurable decreases in the sulfate mass on a per particle basis suggest that the formation of organosulfate compounds is also likely. A portion of the heterogeneous reactions appears to be reversible, consistent with reversible olefin hydration reactions. A slow increase in the organic mass after a fast initial uptake is attributed to irreversible reactions, consistent with polymerization and organosulfate formation. Uptake coefficients (γ) were estimated for a fast initial uptake governed by the mass accommodation coefficient (α) and ranged from 1×10-6–2.5×10−2. Uptake coefficients for a subsequent slower reactive uptake ranged from 1×10-7–1×10-4. These processes are estimated to potentially produce greater than 2.5 μg m−3 of SOA from the various biogenic hydrocarbons under atmospheric conditions, which can be highly significant given the large array of atmospheric olefins.

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Suvarli, Narmin, Iris Perner-Nochta, Jürgen Hubbuch et Michael Wörner. « Thiol-Functional Polymer Nanoparticles via Aerosol Photopolymerization ». Polymers 13, n^o 24 (13 décembre 2021) : 4363. http://dx.doi.org/10.3390/polym13244363.

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Spherical, individual polymer nanoparticles with functional –SH groups were synthesized via aerosol photopolymerization (APP) employing radically initiated thiol-ene chemistry. A series of various thiol and alkene monomer combinations were investigated based on di-, tri-, and tetrafunctional thiols with difunctional allyl and vinyl ethers, and di- and trifunctional acrylates. Only thiol and alkene monomer combinations able to build cross-linked poly(thio-ether) networks were compatible with APP, which requires fast polymerization of the generated droplet aerosol during the photoreactor passage within a residence time of half-minute. Higher monomer functionalities and equal overall stoichiometry of functional groups resulted in the best nanoparticles being spherical and individual, proven by scanning electron microscopy (SEM). The presence of reactive –SH groups in the synthesized nanoparticles as a basis for post-polymerization modifications was verified by Ellman’s test.

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Aqil, Abdelhafid, Farid Ouhib, Christophe Detrembleur et Maryline Moreno-Couranjou. « Atmospheric plasma deposition of bioinspired catechol-rich polymers : a promising route for the simple construction of redox-active thin films ». Materials Advances 2, n^o 4 (2021) : 1248–52. http://dx.doi.org/10.1039/d0ma00865f.

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The atmospheric aerosol assisted plasma polymerization of 4-vinyl-catechol allows the facile deposition of robust redox active catechol-rich films with promising properties as organic cathode materials for lithium ion battery.

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Texter, J., L. E. Oppenheimer et J. R. Minter. « Microemulsion polymerization in the water, aerosol-OT, tetrahydrofurfuryl methacrylate system ». Polymer Bulletin 27, n^o 5 (janvier 1992) : 487–94. http://dx.doi.org/10.1007/bf00300595.

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Musick, J., J. Popp, M. Trunk et W. Kiefer. « Polymerization and copolymerization reaction observed in optically levitated aerosol particles ». Journal of Aerosol Science 27 (septembre 1996) : S561—S562. http://dx.doi.org/10.1016/0021-8502(96)00353-9.

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Kawai, Takeshi, Yoichi Yasuda et Kijiro Kon-no. « Kinetics of Polymerization of Acrylamide in Aerosol OT W/O Microemulsions ». Bulletin of the Chemical Society of Japan 68, n^o 8 (août 1995) : 2175–77. http://dx.doi.org/10.1246/bcsj.68.2175.

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Abdullah, Manal Midhat. « Effect of iodine doping on the characteristics of polythiophene thin films prepared by aerosol assisted plasma jet polymerization at atmospheric pressure ». Iraqi Journal of Physics (IJP) 12, n^o 25 (12 février 2019) : 127–37. http://dx.doi.org/10.30723/ijp.v12i25.313.

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Iodine-doped polythiophene thin films are prepared by aerosol assisted plasma jet polymerization at atmospheric pressure and room temperature. The doping of iodine was carried out in situ by employing iodine crystals in thiophene monomer by weight mixing ratios of 1%, 3%, 5% and 7%. The chemical composition analyses of pure and iodine-doped and heat-treated polythiophene thin films are carried out by FTIR spectroscopy studies. The optical band gaps of the films are evaluated from absorption spectrum studies. Direct transition energy gaps are determined from Tauc plots. The structural changes of polythiophene upon doping and the reduction of optical band gap are explained on the basis of the results obtained from FTIR spectroscopy, UV–VIS absorption studies, X-ray diffraction and atomic force microscope (AFM) analysis. The energy band gap will be different according to the concentration of polythiophene iodine. It can be concluded that iodine-doped polythiophene thin films can be prepare by aerosol assisted plasma jet polymerization and control the optical energy band gap regulars by controlling the thiophene -iodine weight mixing ratios.

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Hohnholz, Arndt, Kotaro Obata, Daniel Albrecht, Jürgen Koch, Gerrit Hohenhoff, Oliver Suttmann, Stefan Kaierle et Ludger Overmeyer. « Multimaterial bathless stereolithography using aerosol jet printing and UV laser based polymerization ». Journal of Laser Applications 31, n^o 2 (mai 2019) : 022301. http://dx.doi.org/10.2351/1.5096106.

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Wang, Qiang, Shi Dong Wang, Hui Min Zhao et Shu Liang Zang. « Synthesis and Characterization of Rhenium Concerned Macroporous Adsorption Resin Microspheres ». Advanced Materials Research 1048 (octobre 2014) : 511–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1048.511.

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The macroporous resin is one kind of new non-ionic organic high polymer absorbent with nearly 20 years development. It takes the styrene and the acrylic ester as the monomer, divinyl benzene as the crosslinking agent, the toluene and the xylene as aperture reagents. They intersectantly linked the polymerization to form the porous skeleton structure mutually. This experiment is the utilization of aerosol polymerization method in preparation of rhenium concerned polymeric adsorbent. On research of monomer and crosslinking agent allocated proportion, dispersing agent amount used, temperature and mixing speed control, the different monomer and the crosslinking agent separately affected the synthesis different macroporous polymeric adsorbent. Also we investigated the adsorption performance quality of the different macroporous polymeric adsorbent in order to make the best particle size.

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Lu, Yang, Clayton Kacica, Sonal Bansal, Luciano M. Santino, Shinjita Acharya, Jiayi Hu, Chiemela Izima et al. « Synthesis of Submicron PEDOT Particles of High Electrical Conductivity via Continuous Aerosol Vapor Polymerization ». ACS Applied Materials & ; Interfaces 11, n^o 50 (19 novembre 2019) : 47320–29. http://dx.doi.org/10.1021/acsami.9b15625.

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Pacios, I. E., C. S. Renamayor, A. Horta, B. Lindman et K. Thuresson. « Polymerization of N,N-dimethylacrylamide in Aerosol OT–water mixtures : from lamellae to segregation ». Colloids and Surfaces A : Physicochemical and Engineering Aspects 218, n^o 1-3 (mai 2003) : 11–20. http://dx.doi.org/10.1016/s0927-7757(02)00583-6.

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Shaban, Masoom, Jalal Poostforooshan et Alfred P. Weber. « Surface-initiated polymerization on unmodified inorganic semiconductor nanoparticles via surfactant-free aerosol-based synthesis toward core–shell nanohybrids with a tunable shell thickness ». Journal of Materials Chemistry A 5, n^o 35 (2017) : 18651–63. http://dx.doi.org/10.1039/c7ta04985d.

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Jang, Hyo Jun, Eun Young Jung, Travis Parsons, Heung-Sik Tae et Choon-Sang Park. « A Review of Plasma Synthesis Methods for Polymer Films and Nanoparticles under Atmospheric Pressure Conditions ». Polymers 13, n^o 14 (10 juillet 2021) : 2267. http://dx.doi.org/10.3390/polym13142267.

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In this paper, we present an overview of recent approaches in the gas/aerosol-through-plasma (GATP) and liquid plasma methods for synthesizing polymer films and nanoparticles (NPs) using an atmospheric-pressure plasma (APP) technique. We hope to aid students and researchers starting out in the polymerization field by compiling the most commonly utilized simple plasma synthesis methods, so that they can readily select a method that best suits their needs. Although APP methods are widely employed for polymer synthesis, and there are many related papers for specific applications, reviews that provide comprehensive coverage of the variations of APP methods for polymer synthesis are rarely reported. We introduce and compile over 50 recent papers on various APP polymerization methods that allow us to discuss the existing challenges and future direction of GATP and solution plasma methods under ambient air conditions for large-area and mass nanoparticle production.

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Nie, Wei, Juan Hong, Silja A. K. Häme, Aijun Ding, Yugen Li, Chao Yan, Liqing Hao et al. « Volatility of mixed atmospheric humic-like substances and ammonium sulfate particles ». Atmospheric Chemistry and Physics 17, n^o 5 (15 mars 2017) : 3659–72. http://dx.doi.org/10.5194/acp-17-3659-2017.

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Abstract. The volatility of organic aerosols remains poorly understood due to the complexity of speciation and multiphase processes. In this study, we extracted humic-like substances (HULIS) from four atmospheric aerosol samples collected at the SORPES station in Nanjing, eastern China, and investigated the volatility behavior of particles at different sizes using a Volatility Tandem Differential Mobility Analyzer (VTDMA). In spite of the large differences in particle mass concentrations, the extracted HULIS from the four samples all revealed very high-oxidation states (O : C > 0.95), indicating secondary formation as the major source of HULIS in Yangtze River Delta (YRD). An overall low volatility was identified for the extracted HULIS, with the volume fraction remaining (VFR) higher than 55 % for all the regenerated HULIS particles at the temperature of 280 °C. A kinetic mass transfer model was applied to the thermodenuder (TD) data to interpret the observed evaporation pattern of HULIS, and to derive the mass fractions of semi-volatile (SVOC), low-volatility (LVOC) and extremely low-volatility components (ELVOC). The results showed that LVOC and ELVOC dominated (more than 80 %) the total volume of HULIS. Atomizing processes led to a size-dependent evaporation of regenerated HULIS particles, and resulted in more ELVOC in smaller particles. In order to understand the role of interaction between inorganic salts and atmospheric organic mixtures in the volatility of an organic aerosol, the evaporation of mixed samples of ammonium sulfate (AS) and HULIS was measured. The results showed a significant but nonlinear influence of ammonium sulfate on the volatility of HULIS. The estimated fraction of ELVOC in the organic part of the largest particles (145 nm) increased from 26 %, in pure HULIS samples, to 93 % in 1 : 3 (mass ratio of HULIS : AS) mixed samples, to 45 % in 2 : 2 mixed samples, and to 70 % in 3 : 1 mixed samples, suggesting that the interaction with ammonium sulfate tends to decrease the volatility of atmospheric organic compounds. Our results demonstrate that HULIS are important low-volatility, or even extremely low-volatility, compounds in the organic-aerosol phase. As important formation pathways of atmospheric HULIS, multiphase processes, including oxidation, oligomerization, polymerization and interaction with inorganic salts, are indicated to be important sources of low-volatility and extremely low-volatility species of organic aerosols.

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Chen, Xiao, Chiara Lo Porto, Zhiqiang Chen, Andrea Merenda, François-Marie Allioux, Riccardo d'Agostino, Kevin Magniez, Xiujuan J. Dai, Fabio Palumbo et Ludovic F. Dumée. « Single step synthesis of Janus nano-composite membranes by atmospheric aerosol plasma polymerization for solvents separation ». Science of The Total Environment 645 (décembre 2018) : 22–33. http://dx.doi.org/10.1016/j.scitotenv.2018.06.343.

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Ogudov, A. S., N. F. Chuenko, N. A. Shestakov, V. S. Bolshakov et M. A. Kreimer. « Assessment histopathological changes in lung laboratory animals under conditions of pentanatrium salt contamination with liquid aerosol ». Interexpo GEO-Siberia 4 (18 mai 2022) : 281–84. http://dx.doi.org/10.33764/2618-981x-2022-4-281-284.

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For the production of polyacrylamides, pentasodium salt of diethylenetriaminepentaacetic acid is used as a polymerization initiator. At this stage, conditions are created for the contamination of the air substance of the working area with a liquid aerosol. The pentasodium salt of diethylenetriaminepentaacetic acid has a chelating ability to bind to trace elements, in particular zinc, which plays an important role in the proliferation of human cells. Zinc homeostasis is required for many aspects of the immune system and is required for an infectious response. According to the literature, the hygienic standards for the content of pentasodium salt of diethylenetriaminepentaacetic acid in the air of the working area have not yet been established. Objective of the study: to evaluate the irritant effect on lung tissue under conditions of liquid aerosol contamination of pentasodium salt of diethylenetriaminepentaacetic acid. The results of inhalation inoculations confirm that as the level of exposure to pentasodium salt of diethylenetriaminepentaacetic acid increases, the risk of damage to the mucous membranes of the respiratory tract increases. The chelating ability of a substance and its accumulation in the human body can lead to a decrease in the bioavailability of trace elements, in particular, to zinc.

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Humud, Hammad R., Ahmad Kudhair Abass et Zahraa Wheeb. « Characteristic of Silver\ Polyaniline Nanocomposite Thin Films Prepared by Aerosol Assisted Dielectric Barrier Discharge Plasma Jet Polymerization ». Asian Journal of Applied Science and Engineering 3, n^o 8 (1 août 2014) : 25. http://dx.doi.org/10.15590/ajase/2014/v3i8/54481.

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Sajjadi, Shahriar. « Particle formation in interval III of the emulsion polymerization of styrene with aerosol-MA as an emulsifier ». Journal of Polymer Science Part A : Polymer Chemistry 40, n^o 10 (4 avril 2002) : 1652–63. http://dx.doi.org/10.1002/pola.10244.

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Dutka, V. S., Ya P. Kovalskyi et G. G. Midyana. « Adsorption of peroxides on aerosils and magnesium oxide ». Voprosy Khimii i Khimicheskoi Tekhnologii, n^o 1 (janvier 2022) : 47–53. http://dx.doi.org/10.32434/0321-4095-2022-140-1-47-53.

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The adsorption of oligomeric peroxide of sebacic acid and benzoyl peroxide on aerosils and magnesium oxide is studied. The parameters of the adsorption processes are determined. It is shown that the adsorption occurs via formation of hydrogen bonds between surface OH-groups of adsorbents and peroxide groups. The adsorption of benzoyl peroxide on the surface of aerosils and magnesium oxide is low. The thermal decomposition of oligomeric peroxide of sebacic acid and benzoyl peroxide in the presence of aerosil is investigated. The thermal decomposition of oligomeric peroxide of sebacic acid in the presence of aerosils is faster than in a homogeneous system. The corresponding activation energy increases as the aerosil content in the system decreases. In contrast to oligomeric peroxide of sebacic acid, aerosils has no effect on the thermal decomposition rate of the benzoyl peroxide. The polymerization of styrene in the presence of aerosil leads to the formation of a mineral-polymer composite. An increase in aerosil content in the polymerization system leads to a decrease in the rate of polymerization of styrene.

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Kim, Yung-Yoon, Kanta Sagara et Kazuya Uezu. « Functional Microfiber Nonwoven Fabric with Sialic Acid-Immobilized Polymer Brush for Capturing Lectin in Aerosol ». Polymers 14, n^o 4 (9 février 2022) : 663. http://dx.doi.org/10.3390/polym14040663.

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The influenza virus has been known as a representative infectious virus that harms human health from the past to the present day. We have promoted the development of a novel adsorbent capable of adsorbing influenza viruses in the form of aerosols in the air. In this study, to develop a material to adsorb the influenza virus, a functional group was introduced into a microfiber nonwoven fabric (MNWF) manufactured through radiation-induced graft polymerization (RIGP), and sialic acid was immobilized to mimic the sugar chain cluster effect. The functional group was used by coupling disodium iminodiacetate monohydrate (IDA) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), and N-acetylneuraminic acid (NANA) was selected for sialic acid. IDA-EDC was introduced into GMA MNWF with an average molar conversion of 47%. For NANA MNWF with a degree of grafting (dg) of 87% introduced with sialic acid, 118.2 of 200 µg of aerosolized lectin was adsorbed, confirming that the maximum adsorption amount was 59.1%. In NANA MNWF of 100% or more dg, a tendency to decrease the amount of lectin adsorption was observed compared to NANA MNWF of 80–100% dg.

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Chidichimo, Giuseppe, Alessandra Crispini, Antonio Tursi, Maria Rita Basile, Ilaria Lania, Giovanni De Filpo, Cesare Oliviero Rossi et Francesca Scarpelli. « Water-Based Aerosol for Book Deacidification : Experimental Apparatus and Theoretical Interpretation of Results ». Molecules 26, n^o 14 (13 juillet 2021) : 4249. http://dx.doi.org/10.3390/molecules26144249.

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One of the major problems in book conservation is the long-term deconstructive effect of acidity introduced into the paper by several additives, which, in the presence of humidity, generates a hydrogen cation with a strong catalytic role in cellulose depolymerization. Many types of treatment have been used in the past, but up to now, research for less-invasive, fast and cheap methods is still vividly ongoing. In this study, an approach to book deacidification is presented, where alkaline water solutions are administered to bound books in the form of micrometer-sized aerosol droplets, without using vacuum apparatus accessories. Alkaline clouds treatments were alternated with gentle air fluxes of drying steps. Few cycles are required to achieve uniform deacidification of books. The treatment could be conducted with proper apparatus on large volumes, resulting in rapid treatment time and low cost. The titration curve reporting the variation of book pH, with respect to the amount of absorbed alkaline aerosol, was built and interpreted in terms of a chemical model for the neutralization process. FTIR, PXRD and XRF spectroscopies were used to characterize the book chemistry. The effects of the treatment on the book were evaluated by measuring the degree of polymerization (DP) of the paper and the colorimetric coordinates of the paper and ink. Artificial aging tests revealed a general increase in the aging stability of the deacidified paper samples with respect to the untreated samples. Finally, the alkaline reserve data are discussed.

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Cho, Young-Sang, Younghyun Lee, Nahee Ku, Sugueun Ji et Young Seok Kim. « Synthesis of Porous Particles by Electrospray-Assisted Self-Assembly for Water-Repellent or Photocatalytic Surfaces ». Korean Journal of Metals and Materials 58, n^o 2 (5 février 2020) : 112–24. http://dx.doi.org/10.3365/kjmm.2020.58.2.112.

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In this study, an electrospray technique was used for the synthesis of macroporous ceramic particles, such as silica or titania, by a colloidal templating method. For this purpose, a suspension of polystyrene nanospheres was synthesized by dispersion polymerization for use as sacrificial templates. The feed solution containing a ceramic precursor and polymeric beads was injected through a metallic nozzle under a high electric field for nebulization of aerosol droplets as micro-reactors. Under ambient air conditions, the volatile components were evaporated from the droplets, and gelation of the precursor was completed simultaneously. The resulting supra-aggregates were then collected, and calcination was performed to form porous ceramic particles by removing the polymeric templates. As a demonstrative application, the porous particles of silica were deposited as a coating film for superhydrophobic surfaces with a high water contact angle larger than 150°. Furthermore, macroporous titania particles were used as photocatalytic particles in a wastewater system with first-order reaction kinetics.

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Zahardis, James, Brian W. LaFranchi et Giuseppe A. Petrucci. « Direct observation of polymerization in the oleic acid–ozone heterogeneous reaction system by photoelectron resonance capture ionization aerosol mass spectrometry ». Atmospheric Environment 40, n^o 9 (mars 2006) : 1661–70. http://dx.doi.org/10.1016/j.atmosenv.2005.10.065.

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Taqa, Ala Abu, Ghassan Suleiman, Ahmed Senouci, Mwfeq Al-Haddad, Dua’a Omran Al-Masri, Mohamed Al-Ansari et Mohamed O. Mohsen. « Aerosol OT Quantity Impacts on Calcium Nitrate Self-Healing Microcapsule Properties Used for Sustainable Construction Applications ». Buildings 12, n^o 12 (2 décembre 2022) : 2121. http://dx.doi.org/10.3390/buildings12122121.

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This paper is a continuation of a previously published paper on this issue that studied the microencapsulation of calcium nitrate in urea-formaldehyde shell using Aerosol OT (AOT) in hexane solution. The aim of this paper is to determine the quantity of AOT that optimizes microcapsule distribution, diameter, and shell thickness. Different quantities of AOT, namely 0.25 g, 0.50 g, 1.5 g, and 2.5 g were dissolved in 180 g of hexane solution to prepare the continuous phase. A Scanning Electron Microscopy (SEM) was used to characterize the distribution and the diameters of the prepared microcapsules. A Transmission Electron Microscopy (TEM) was used to investigate the microcapsule shell thicknesses. The SEM images have shown that using 0.25 g of AOT may be insufficient to totally polymerize the whole quantity of the core materials into fully independent capsules. On the other hand, using 0.50 g of AOT has shown a uniform distribution and almost complete polymerization of the core material components into distinct microcapsules. Higher quantities of AOT (i.e., 1.50 g and 2.5 g) have resulted in agglomerated microcapsules and nonuniform distributions. The results have also demonstrated that the quantity of AOT does not have a significant impact on the microcapsule diameter. Microcapsule average shell thicknesses were found to decrease by increasing AOT amount up to 0.50 g and to increase again due to the agglomeration witnessed for increased AOT quantity. Accordingly, 0.50 g of AOT was recommended for the preparation of calcium nitrate microcapsules in future research work.

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Farías-Cepeda, Lorena, Jorge Herrera-Ordonez et Enrique Saldívar-Guerra. « On the kinetics and particle size polydispersity of the styrene emulsion polymerization using aerosol MA80 and sodium dodecyl sulfate as surfactants ». Colloid and Polymer Science 288, n^o 14-15 (13 août 2010) : 1401–9. http://dx.doi.org/10.1007/s00396-010-2272-0.

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Li, Y. J., D. D. Huang, H. Y. Cheung, A. K. Y. Lee et C. K. Chan. « Aqueous-phase photochemical oxidation and direct photolysis of vanillin &ndash ; a model compound of methoxy-phenols from biomass burning ». Atmospheric Chemistry and Physics Discussions 13, n^o 10 (25 octobre 2013) : 27641–75. http://dx.doi.org/10.5194/acpd-13-27641-2013.

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Abstract. We present here experimental results on aqueous-phase (A) photochemical oxidation (with UV and OH radicals generated from H2O2 photolysis) and (B) direct photolysis (with only UV irradiation) of a methoxy-phenol, vanillin (VL), as a model compound from biomass burning. Both on-line aerosol mass spectrometric (AMS) characterization and off-line chemical analyses were performed. AMS analyses of dried atomized droplets of the bulk reacting mixtures showed that VL almost entirely evaporates during the drying process. Large amounts of organic mass remained in the particle phase after reactions under both conditions. Under condition (A), AMS measured organic mass first increased rapidly and then decreased, attributable to the formation of non-volatile products and subsequent formation of smaller and volatile products, respectively. The oxygen-to-carbon (O:C) ratio of the products reached 1.5 after about 80 min, but dropped substantially thereafter. In contrast, organic mass increased slowly under condition (B). The O:C ratio reached 1.0 after 180 min. In off-line analyses, small oxygenates were detected under condition (A), while hydroxylated products and dimers of VL were detected under condition (B). Particle hygroscopic growth factor (GF) and cloud condensation nuclei (CCN) activity of the reacting mixtures were found to be dependent on both organic volume fraction and the degree of oxygenation of organics. Results show that (1) aqueous-phase processes can lead to the retention of a large portion of the organic mass in the particle phase; (2) once retained, this portion of organic mass significantly changes the hygroscopicity and CCN activity of the aerosol particles; (3) intensive photochemical oxidation gave rise to an O:C ratio as high as 1.5 but the ratio decreased as further oxidation led to smaller and more volatile products; and (4) polymerization occurred with direct photolysis, resulting in high-molecular-weight products of a yellowish color. This study demonstrates that aqueous-phase reactions of a methoxy-phenol can lead to substantial amount of secondary organic aerosol (SOA) formation. Given the vast amount of biomass burning input globally, model representation of either the SOA budget or their subsequent effects would not be adequate if the contribution of SOA formation from aqueous-phase reactions of methoxy-phenols is not considered.

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Li, Y. J., D. D. Huang, H. Y. Cheung, A. K. Y. Lee et C. K. Chan. « Aqueous-phase photochemical oxidation and direct photolysis of vanillin – a model compound of methoxy phenols from biomass burning ». Atmospheric Chemistry and Physics 14, n^o 6 (19 mars 2014) : 2871–85. http://dx.doi.org/10.5194/acp-14-2871-2014.

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Abstract. We present here experimental results on aqueous-phase (A) photochemical oxidation (with UV and OH radicals generated from H2O2 photolysis) and (B) direct photolysis (with only UV irradiation) of a methoxy phenol, vanillin (VL), as a model compound from biomass burning. Both on-line aerosol mass spectrometric (AMS) characterization and off-line chemical analyses were performed. AMS analyses of dried atomized droplets of the bulk reacting mixtures showed that VL almost entirely evaporates during the drying process. Large amounts of organic mass remained in the particle phase after reactions under both conditions. Under condition (A), AMS measured organic mass first increased rapidly and then decreased, attributable to the formation of non-volatile products and subsequent formation of smaller and volatile products, respectively. The oxygen-to-carbon (O : C) ratio of the products reached 1.5 after about 80 min, but dropped substantially thereafter. In contrast, organic mass increased slowly under condition (B). The O : C ratio reached 1.0 after 180 min. In off-line analyses, small oxygenates were detected under condition (A), while hydroxylated products and dimers of VL were detected under condition (B). Particle hygroscopic growth factor (GF) and cloud condensation nuclei (CCN) activity of the reacting mixtures were found to depend on both organic volume fraction and the degree of oxygenation of organics. Results show that (1) aqueous-phase processes can lead to the retention of a large portion of the organic mass in the particle phase; (2) once retained, this portion of organic mass significantly changes the hygroscopicity and CCN activity of the aerosol particles; (3) intensive photochemical oxidation gave rise to an O : C ratio as high as 1.5 but the ratio decreased as further oxidation led to smaller and more volatile products; and (4) polymerization occurred with direct photolysis, resulting in high-molecular-weight products of a yellowish color. This study demonstrates that aqueous-phase reactions of a methoxy phenol can lead to substantial amount of secondary organic aerosol (SOA) formation. Given the vast amount of biomass burning input globally, model representation of either the SOA budget or their subsequent effects would not be adequate if the contribution of SOA formation from aqueous-phase reactions of methoxy phenols is not considered.

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Taqa, Ala Abu, Ghassan Suleiman, Ahmed Senouci et Mohamed O. Mohsen. « Using Aerosol OT in Hexane Solution to Synthesize Calcium Nitrate Self-Healing Refined Microcapsules for Construction Applications ». Buildings 12, n^o 6 (31 mai 2022) : 751. http://dx.doi.org/10.3390/buildings12060751.

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The micro-encapsulation procedure of calcium nitrate in urea-formaldehyde shell is well known. The most recent developed method for the synthesis of the calcium nitrate self-healing micro-capsules was based on the in-situ polymerization using water-in-oil emulsion. Although the microcapsules’ yield was significantly improved using this approach, incorporating the micro-capsules into concrete mixes has been found to reduce strength. One potential strength reduction cause might be the presence of sulfonic acid as a component in the continuous (oil) phase. As the anionic surfactant, Aerosol OT (AOT) has been widely used to prepare water-in-oil emulsions and to form aggregates in non-polar solvents; submicron calcium nitrate refined microcapsules were synthesized using AOT in hexane solution. While the aqueous phase in the original encapsulation procedure has not been altered, the continuous organic phase was prepared by dissolving AOT in hexane. The prepared microcapsules were characterized using Scanning Electron Microscopy (SEM). The preliminary assessment of the effect of incorporating of the refined microcapsules into cementitious materials has been carried out by preparing mortar mixes using 75% capsules’ concentration (by weight of cement). The reported yield values, average shell thickness, and average diameter of the prepared microcapsules were found satisfactory. Moreover, the mortar samples containing calcium nitrate refined microcapsules that were prepared using the proposed method did not experience significant reduction in their mechanical properties. Hence, such encapsulation procedure may be adopted for further investigation of the self-healing efficiency in cementitious materials of the microcapsules prepared using the proposed procedure. Future work shall be directed towards this end.

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Kim, Kyoungho. « High Operating Voltage Supercapacitor Using PPy/AC Composite Electrode Based on Simple Dipping Method ». Journal of Chemistry 2015 (2015) : 1–7. http://dx.doi.org/10.1155/2015/314893.

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As various wearable devices are emerging, self-generated power sources, such as piezoelectric generators, triboelectric generators, and thermoelectric generators, are of interest. To adapt self-generated power sources for application devices, a supercapacitor is necessary because of the short generation times (1–10 ms) and low generated power (1–100 μW) of self-generated power sources. However, to date, supercapacitors are too large to be adapted for wearable devices. There have been many efforts to reduce the size of supercapacitors by using polypyrrole (PPy) for high energy supercapacitor electrodes. However, these supercapacitors have several disadvantages, such as a low operating voltage due to the use of an aqueous electrolyte, and complex manufacturing methods, such as the hydrogel and aerosol methods. In particular, the low operating voltage (~1.0 V) is a significant issue because most electronic components operate above 3.0 V. In this study, we successfully demonstrated the high operating voltage (3.0 V) of a supercapacitor using a PPy/activated carbon (AC) composite electrode based on the chemical polymerization of the PPy by simple dipping. In addition, a twofold enhancement of its energy density was achieved compared with conventional supercapacitors using AC electrodes.

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Cheng, Yun-Chien, Chun-Ping Hsiao, Yung-Hsin Liu, Chu-Hao Yang, Chun-Yi Chiang, Tsung-Rong Lin, Yi-Wei Yang et Jong-Shinn Wu. « Enhancing adhesion and polymerization of lipase-plasma-polymerized-ethylene coatings deposited with planar dielectric-barrier-discharge-type aerosol-assisted atmospheric-pressure plasma system ». Plasma Processes and Polymers 15, n^o 4 (23 février 2018) : 1700173. http://dx.doi.org/10.1002/ppap.201700173.

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Chandra, H., A. K. Saraf, R. K. Jadhav, G. J. Rao, V. K. Sharma, S. Sriramachari et M. Vairamani. « Isolation of an Unknown Compound, from Both Blood of Bhopal Aerosol Disaster Victims and Residue of Tank E-610 of Union Carbide India Limited — Chemical Characterization of the Structure ». Medicine, Science and the Law 34, n^o 2 (avril 1994) : 106–10. http://dx.doi.org/10.1177/002580249403400204.

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A total of more than 28 chemical entities/reaction products in the form of gases, vapour and particulate matter were reported from the tank E-610 of methyl isocyanate (MIC) storage tank of Union Carbide India Limited on the night of 2/3 December 1984 in Bhopal. In earlier studies, methyl isocyanate and its trimer, with a few other compounds, were reported in the human victims preserved in deep freeze. Randomly selected samples were analysed by gas Chromatograph coupled with mass spectrometer (ITD-800, Finnigan MAT, UK). Four of the cases showed the peaks and fragmentation pattern identified with one of the unidentified compound of molecular weight 269 amu in the Tank Residue, which constituted about 0.2 area per cent on GC-ITD. After isolation by column chromatography and being exposed to characterization, it was identified as a Spiro compound. It was possibly formed by the polymerization of five molecules of methyl isocyanate.

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Nikiforov, Anton, Rino Morent et Chuanlong Ma. « (Invited) Plasma Technology in Surface Engineering : From Super-Hydrophilic to Super-Hydrophobic Materials ». ECS Meeting Abstracts MA2022-02, n^o 18 (9 octobre 2022) : 865. http://dx.doi.org/10.1149/ma2022-0218865mtgabs.

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Materials surface wettability is a fundamental property of a solid. Wettability plays a paramount role in the everyday applications of solid materials in many fields of science and technology. Numerous examples include advanced membranes (from water purification to biopharmaceuticals), energy storage devices, windows, raincoats, roofs, disposable diapers, microfluidics, bandages, tissue scaffolds, and bio-implants. With the continuous development of modern society, the demand for advanced functional materials with the desirable surface wettability is increasing faster than ever before. This is why precise control over surface wettability is expected to provide materials with superior properties for unprecedented applications in diverse fields. Over the past decade, conventional wet chemistry approaches have been among the most frequently used methods for surface wettability control. However, they are often energy-inefficient, pollute the environment, and rely on harsh synthesis conditions. Recently, low-temperature plasma processing has attracted major attention in surface wettability control. The reason for this particular interest is because plasma processing is highly-selective, environmentally friendly, and low-cost. Plasma processing can uniquely modify both the surface chemistry and surface topography for a wide range of materials. Moreover, it can be operated at very mild conditions such as room temperature, atmospheric pressure, and open-air environments. Plasma can be used as a controlled reactive physicochemical environment for surface activation, coating deposition, and nanostructuring of diverse materials. The unique plasma-specific conditions and effects allow precise control over microscopic surface chemical composition and surface nanostructures by adjusting the macroscopical energy input. Accordingly, effective control over surface wettability can be achieved for a broad range of hard and soft materials. An environmentally friendly, large scale and low-cost wetting control method that does not result in bulk damage, would result in improvement of industrial applications. A possible solution to this wetting control problem is atmospheric-pressure plasma (APP), especially the plasma generated in open-air due to the benefits of solvent-free treatment, requiring no vacuum systems and suitable for in-line processes. In the current work, we will give a comprehensive overview of different atmospheric pressure plasma processes capable to change the surface properties of the polymers with little or no change of the bulk. Two main approaches: (i) plasma activation introducing oxygen-containing groups into the material surface; (ii) plasma polymerization directed to the change of the surface composition will be highlighted and background will be explained. Recently our team developed a new approach based on the use of a combination of plasma activation and plasma polymerization, two different plasma techniques in a single process to achieve different surface wetting properties from hydrophilic to hydrophobic, with the high long-term stability of the coatings in water. Such a type of research approach realized in one plasma source was not yet applied for wettability control and has very promising application potential in the industrial processing of polymers. For surface engineering, and easy to scale-up the radio frequency (RF) plasma system was adopted to perform both plasma activation and plasma polymerization on PET substrate in the atmospheric pressure in the open air. Different characterization methods including WCA measurements, Fourier-transform infrared spectroscopy (FT-IR), XPS, and atomic force microscopy (AFM) were applied to get an insight into surface chemistry and morphology and the effect of the combination of the plasma activation with plasma polymerization. The developed approach has shown the capability of stable coatings deposition with the use of acrylic acid, HMDSO or fluorine-containing precursors PFDA. We demonstrate a single-step, fast, green, cheap, and universal plasma-based approach with potential for large-scale production of oil/water separation membranes, namely aerosol-assisted plasma deposition (AAPD). A hydrophobic polyester membrane is exposed to an in-line atmospheric pressure plasma coupled with an aerosol of a 2-hydroxyethyl methacrylate (HEMA) monomer. A plasma polymerized HEMA thin film is thus successfully coated on the membrane, resulting in an superhydrophilic/underwater superoleophobic surface. With created coating, the water pre-wetted plasma-functionalized polyester membrane shows an ultrahigh separation efficiency above 97.8% towards various oil/water mixtures and a superb water flux above 35.6 L m-2 s-1. Importantly, it also exhibits excellent performance in anti-oil-fouling, recyclability, and durability, indicating its high potential in real-life usage. To further examine the universality of the proposed approach, another hydrophilic monomer (acrylic acid) is also used to functionalize the polyester membranes. The obtained functionalized membranes can also efficiently separate diversified oil/water mixtures. Therefore, this study demonstrates the capability of plasma-based surface engineering methods to manipulate surface properties of materials in a very wide range from superhydrophobic to hydrophilic and even super-hydrophilic which opens new areas of applications.

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Karimi, Maryam, Soroush Davoudizadeh, Saeed Bahadorikhalili et Khezrollah Khezri. « Investigating the Effect of Silica Aerogel Nanoparticles on the Kinetics of AGET ATRP of Methyl Methacrylate ». Zeitschrift für Physikalische Chemie 233, n^o 3 (26 mars 2019) : 393–411. http://dx.doi.org/10.1515/zpch-2018-1202.

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Abstract Hexamethyldisilazane-modified silica aerogel nanoparticles were used for in situ polymerization of methyl methacrylate by activators generated by electron transfer for atom transfer radical polymerization (AGET ATRP) to synthesize tailor-made PMMA nanocomposites. Appropriate dispersion of silica aerogel nanoparticles in the monomer solution and improvement in interfacial interaction between the PMMA matrix and nanoparticles are two main reasons for application of HMDS-modified silica aerogel nanoparticles. Nitrogen adsorption/desorption isotherm was employed to examine surface area and structural characteristics of the HMDS-modified silica aerogel nanoparticles. Evaluation of size distribution and morphological studies were also performed by SEM and TEM. Conversion and molecular weight determinations were carried out using GC and SEC, respectively. Addition of 3 wt% HMDS-modified silica aerogel nanoparticles leads to decrement of conversion from 85 to 64%. Molecular weight of PMMA chains also decreases from 13,912 to 10,810 g⋅mol−1 by addition of only 3 wt% HMDS-modified silica aerogel nanoparticles; however, polydispersity index values increases from 1.18 to 1.51. Linear increase of ln(M0/M) with time for all the samples shows that polymerization proceeds in a living manner. In addition, suitable agreement between theoretical and experimental molecular weight in combination with low PDI values can appropriately demonstrate the living nature of the polymerization. TGA results indicate that by increasing HMDS-modified silica aerogel nanoparticles content, slight improvements in thermal stability of the nanocomposites were obtained. DSC results show a decrease in Tg from 86.9 to 80.1°C by addition of 3 wt% HMDS-modified silica aerogel nanoparticles.

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Guo, Hui, Li Jun Su, Wen Jing Li et Ying Min Zhao. « Study of Carbon Aerogel Composites for Thermal Protection Applications ». Key Engineering Materials 845 (mai 2020) : 9–14. http://dx.doi.org/10.4028/www.scientific.net/kem.845.9.

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Carbon aerogel composites have been prepared by condensation polymerization and high temperature pyrolysis. The morphology of carbon aerogel is characterized by SEM. The pore structure is characterized by N2 adsorption-desorption technique. The thermal insulation properties of carbon aerogel composites are tested. Carbon aerogel composites show good thermal insulation and high temperature resistance in inert atmosphere The results show that they are suitable for applications in aerospace thermal protection industry.

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Quan, Xueping, Zhibing Fu, Lei Yuan, Minglong Zhong, Rui Mi, Xi Yang, Yong Yi et Chaoyang Wang. « Capacitive deionization of NaCl solutions with ambient pressure dried carbon aerogel microsphere electrodes ». RSC Advances 7, n^o 57 (2017) : 35875–82. http://dx.doi.org/10.1039/c7ra05226j.

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Zhang, Longfei, Li Yang, Yewei Xu et Guanjun Chang. « Renewable 4-HIF/NaOH aerogel for efficient methylene blue removal via cation–π interaction induced electrostatic interaction ». RSC Advances 9, n^o 51 (2019) : 29772–78. http://dx.doi.org/10.1039/c9ra04166d.

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Li, Hong Wei, Na Lv, Pan Yan Lu, Gang Qiang Geng et Wei Wang. « Fabrication and Characterization of Silica Aerogel @Polystyrene Composite Beads by Suspension Polymerization ». Materials Science Forum 804 (octobre 2014) : 199–202. http://dx.doi.org/10.4028/www.scientific.net/msf.804.199.

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In this study, the powder of hydrophobic silica aerogel remaining nanopore by ambient pressure drying was successfully introduced into polystyrene beads during suspension polymerization. nanosilica powder without nanopore was also used. Pure polystyrene, silica aerogel/polystyrene (PS) and nanosilica/polystyrene beads were fabricated, respectively. The structure and properties of silica aerogel @PS composite beads were characterized by SEM, EDS, TG-DSC and FT-IR. The results of TG-DSC, FT-IR and EDS show silica aerogel is located in the PS beads, but it is difficult to be observed by SEM because of its low content. The introduction of silica and silica aerogel both decrease the transparency of PS beads. Silica aerogel loosen the microstructure of PS beads.

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Yang, Guangjie, Tianli Ning, Wei Zhao, Wenxiu Deng et Xikui Liu. « Robust ambient pressure dried polyimide aerogels and their graphene oxide directed growth of 1D–2D nanohybrid aerogels using water as the only solvent ». RSC Advances 7, n^o 26 (2017) : 16210–16. http://dx.doi.org/10.1039/c7ra01751k.

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Through soft/hard template directed hydrothermal polymerization, we reported the first green approach to the morpho-controlled synthesis of monolithic polyimide aerogels and their graphene nanohybrid aerogel using nothing but water.

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Lin, Bin, Zufei Wang, Qing-jun Zhu, Wafaa Nazurah Binti Hamzah, Zhen Yao et Kun Cao. « Aerogels for the separation of asphalt-containing oil–water mixtures and the effect of asphalt stabilizer ». RSC Advances 10, n^o 42 (2020) : 24840–46. http://dx.doi.org/10.1039/d0ra00544d.

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In order to separate the asphalt-containing oil–water mixture, an aerogel film was produced through supercritical drying of a polymer gel synthesized using the ring opening metathesis polymerization of dicyclopentadiene (DCPD).

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Su, Jin-Dong, Xian-Sheng Jia, Jin-Tao Li, Tao Lou, Xu Yan, Jia-Lin Sun, Jun-Hong Chen et Yun-Ze Long. « A Three-Dimensional Porous Conducting Polymer Composite with Ultralow Density and Highly Sensitive Pressure Sensing Properties ». Journal of Nanomaterials 2016 (2016) : 1–8. http://dx.doi.org/10.1155/2016/5164012.

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An ultralight conducting polyaniline/SiC/polyacrylonitrile (PANI/SiC/PAN) composite was fabricated by in situ polymerization of aniline monomer on the surface of fibers in SiC/PAN aerogel. The SiC/PAN aerogel was obtained by electrospinning, freeze-drying, and heat treatment. The ingredient, morphology, structure, and electrical properties of the aerogel before and after in situ polymerization were investigated by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and voltage-current characteristic measurement. The thermostability of PANI/SiC/PAN composite was investigated by thermogravimetric analysis (TGA) and electrical resistance measured at different temperatures. The density of the PANI/SiC/PAN composite was approximately 0.211 g cm−3, the porosity was 76.44%, and the conductivity was 0.013 S m−1. The pressure sensing properties were evaluated at room temperature. The electrical resistance of as-prepared sample decreased gradually with the increase of pressure. Furthermore, the pressure sensing process was reversible and the response time was short (about 1 s). This composite may have application in pressure sensor field.

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Bailly, Bérangère, Anne-Carole Donnenwirth, Christèle Bartholome, Emmanuel Beyou et Elodie Bourgeat-Lami. « Silica-Polystyrene Nanocomposite Particles Synthesized by Nitroxide-Mediated Polymerization and Their Encapsulation through Miniemulsion Polymerization ». Journal of Nanomaterials 2006 (2006) : 1–10. http://dx.doi.org/10.1155/jnm/2006/76371.

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Polystyrene (PS) chains with molecular weights comprised between 8000 and 64000g⋅mol-1and narrow polydispersities were grown from the surface of silica nanoparticles (Aerosil A200 fumed silica and Stöber silica, resp.) through nitroxide-mediated polymerization (NMP). Alkoxyamine initiators based on N-tert-butyl-1-diethylphosphono-2,2-dimethylpropyl nitroxide (DEPN) and carrying a terminal functional group have been synthesized in situ and grafted to the silica surface. The resulting grafted alkoxyamines have been employed to initiate the growth of polystyrene chains from the inorganic surface. The maximum grafting density of the surface-tethered PS chains was estimated and seemed to be limited by initiator confinement at the interface. Then, the PS-grafted Stöber silica nanoparticles were entrapped inside latex particles via miniemulsion polymerization. Transmission electron microscopy indicated the successful formation of silica-polystyrene core-shell particles.

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Liu, Zhiyan, Rui Ma, Wenjie Du, Gang Yang et Tao Chen. « Radiation-initiated high strength chitosan/lithium sulfonate double network hydrogel/aerogel with porosity and stability for efficient CO2 capture ». RSC Advances 11, n^o 33 (2021) : 20486–97. http://dx.doi.org/10.1039/d1ra03041h.

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Chitosan hydrogel is regenerated from alkali/urea aqueous solution and the lithium sulfonate second network is introduced by electron beam radiation-initiated in situ free radical polymerization. The freeze-dried aerogel has CO₂ capture capacity.

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Xing, Chen, Yan Zhang, Yang Gao, Yijun Kang et Shiguo Zhang. « N,P co-doped microporous carbon as a metal-free catalyst for the selective oxidation of alcohols by air in water ». New Journal of Chemistry 45, n^o 31 (2021) : 13877–84. http://dx.doi.org/10.1039/d1nj02042k.

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NPMCs are fabricated from one-step pyrolysis of an aerogel precursor derived from direct polymerization of p-phenylenediamine with phytic acid, which can be used as metal-free catalysts for highly selective oxidation of alcohols by air in water.

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Xu, Manman, Weiqi Bao, Shouping Xu, Xiaohui Wang et Runcang Sun. « Porous Cellulose Aerogels with High Mechanical Performance and their Absorption Behaviors ». BioResources 11, n^o 1 (5 novembre 2015) : 8–20. http://dx.doi.org/10.15376/biores.11.1.8-20.

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Porous cellulose aerogel materials are attracting increasing interest due to their promising potential in multiple fields. In this paper, highly porous and mechanically strong cellulose aerogels were successfully prepared from microcrystalline cellulose and dissolving pulp in ionic liquid BmimCl via a sol–gel polymerization method. The surface morphology and physical properties were characterized by scanning electron microscopy, X-ray diffraction, and compression tests, etc. The differences in microstructure, crystalline structure, and mechanical performance of these two kinds of cellulose aerogels were studied and compared. Moreover, the two cellulose aerogels were used as adsorbents to remove dye, oil, and organic solvents. The kinetics and equilibrium capacity were investigated. Results indicate that the cellulose aerogels with high degrees of polymerization have much better mechanical strength and adsorption properties than the cellulose aerogels with low degrees of polymerization.

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Li, Mengjiao, Qinglin Deng, Junyong Wang, Kai Jiang, Zhigao Hu et Junhao Chu. « In situ carbon encapsulation of vertical MoS2 arrays with SnO2 for durable high rate lithium storage : dominant pseudocapacitive behavior ». Nanoscale 10, n^o 2 (2018) : 741–51. http://dx.doi.org/10.1039/c7nr07359c.

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An in situ polymerization–carbonization process for novel carbon-sealed vertical MoS₂–SnO₂ anchored on graphene aerogel (C@MoS₂–SnO₂@Gr) has enabled excellent rate performance and durability as the lithium ion batteries anode.

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Aslamazova, T. R., T. A. Karpukhina, V. I. Yeliseyeva, Ye M. Morozova et V. F. Chuvayev. « Effect of aerosil on radical polymerization in media with crosslinked structures ». Polymer Science U.S.S.R. 27, n^o 11 (janvier 1985) : 2668–72. http://dx.doi.org/10.1016/0032-3950(85)90465-4.

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Massoudinejad, Mohamadreza, Yalda Hashempour et Hamed Mohammad. « Evaluation of Carbon Aerogel Manufacturing Process in Order to Desalination of Saline and Brackish Water in Laboratory Scale ». Civil Engineering Journal 4, n^o 1 (7 février 2018) : 212. http://dx.doi.org/10.28991/cej-030980.

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Carbon aerogel its fabrication and characterization and its uses in this process were studied for desalinating of saline and brackish water. The carbon aerogel manufacturing process involves the polymerization and pyrolysis of the mixture of resorcinol and formaldehyde. Carbon aerogels were analyzed using BET, BJH, and T-plot after construction. The effect of various parameters (including the influent salt concentration, the intensity of electric current flow, the distance between the electrodes and pH) on salt adsorption were studied. Analysis of BET/BJH shown that the surface of aerogel was 677.8 m2/g. much of porosity in the samples of carbon aerogel were between 1-2 nm, namely micro-pour and a similar level 0f 456 m2/gr is dedicated to micro-pour, with a correlation coefficient (r) equal to 94.5. According to the results, it seems that carbon aerogel electrodes have a good structure in desalination of brackish and saline water.

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