1,233 results on '"Phenolic Resin"'
Search Results
752. CARACTERIZAÇÃO DE PAINÉIS LAMINADOS COLADOS PRODUZIDOS COM TALISCAS DE BAMBU (Guadua magna) NATIVO DO CERRADO
- Author
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Teixeira, Divino Eterno, Bastos, Rodrigo Pinheiro, and Almeida, Sergio Alberto de Oliveira
- Subjects
Propriedades ,Phenolic resin ,properties ,Taquaruçu ,PVA ,Resina fenólica ,lcsh:SD1-669.5 ,lcsh:Forestry - Abstract
Panels were produced with strips of bamboo (Guadua magna) in layers crossed at angles of 90° and bonded with phenol-formaldehyde or PVA based resin, glued in three and five plies. The panels were tested and the physical and mechanical properties determined. The tests were primarily related to the commercial adhesives used as well as the number of layers of bamboo used. The density ranged from 0.690 to 0.768 g.cm-3. Panels bonded with PVA resin showed low mechanical strength, with MOR between 6.7 and 7.8 MPa. Those bonded with phenol-formaldehyde adhesive showed high strength, with modulus of rupture (MOR) ranging from 55.5 to 87.0 MPa, which is excellent for boards similar to wood-based panels. Panels with phenolic resin also had reduced thickness swelling, up to 8.4%. The panels made with three layers showed higher resistance to bending than those made with five layers. RESUMO Painéis foram produzidos com taliscas de bambu (Guadua magna) montados em três ou cinco camadas cruzadas entre si em ângulo de 90° e coladas com resina à base de fenol-formaldeído ou PVA. Os painéis foram testados e as propriedades físicas e mecânicas determinadas. Os testes foram quanto aos adesivos comerciais usados, bem como a quantidade de camadas dos painéis. A densidade variou entre 0,690 e 0,768 g.cm-3. Painéis colados com resina PVA mostraram baixa resistência mecânica, apresentando MOR entre 6,7 e 7,8 MPa. Os colados com resina fenol-formaldeído foram mais resistentes, com módulo de ruptura (MOR) entre 55,5 e 87,0 MPa, excelente para painéis similares à base de madeira. Painéis com resina fenólica apresentaram também reduzido inchamento em espessura, até 8,4%. Os painéis produzidos em três camadas apresentaram resistência maior à flexão que os com cinco camadas.
- Published
- 2015
753. Preparation of single-handed helical and C-shaped 3-aminophenol-formaldehyde resin nanotubes and single-handed helical carbonaceous nanotubes
- Author
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Cao, Yanfang, Liu, Dan, Li, Baozong, Li, Yi, and Yang, Yonggang
- Published
- 2016
- Full Text
- View/download PDF
754. Cyanate ester resin modified by phenolic resin containing diphenyl oxide segments with high molecular weight
- Author
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Tu, Yonghui, Yu, Ruobing, Duan, Jiazhen, and Hu, Lin
- Published
- 2016
- Full Text
- View/download PDF
755. Low-Temperature Catalytic Graphitization of Phenolic Resin Using a Co-Ni Bimetallic Catalyst
- Author
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Wang, J., Deng, X., Zhang, H., Duan, H., Cheng, F., and Zhang, S.
- Published
- 2016
- Full Text
- View/download PDF
756. Synthesis of High-Water-Resistance Lignin-Phenol Resin Adhesive with Furfural as a Crosslinking Agent
- Author
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Chen Ding, Jindi Xu, Zhikang Chen, Qi Zheng, Yufei Zhang, Qiulu Meng, and Ning Li
- Subjects
integumentary system ,Polymers and Plastics ,technology, industry, and agriculture ,Substituent ,lignin ,furfural ,General Chemistry ,Furfural ,Article ,lcsh:QD241-441 ,chemistry.chemical_compound ,Viscosity ,lcsh:Organic chemistry ,chemistry ,Chemical engineering ,phenolic resin ,Lignin ,Phenol ,Thermal stability ,Adhesive ,Fourier transform infrared spectroscopy - Abstract
In this study, furfural was used as a crosslinking agent to enhance the water resistance of lignin-phenol-formaldehyde (LPF) resin. The effect of the furfural content on the physicochemical properties of the adhesives was explored, and the possible synthesis mechanism of the furfural-modified lignin-phenol-formaldehyde (LPFF) resin adhesives was investigated. Compared with the LPF adhesive, the LPFF adhesive with 15% furfural content and 50% lignin substituent exhibited outstanding properties in all considered aspects; it had a high wet shear strength (1.30 MPa), moderate solid content (54.51%), and low viscosity (128 mPa∙s), which were 38.0% higher, 3.6% higher, and 37.5% lower than those of the LPF adhesive. Analyses via nuclear magnetic resonance and Fourier transform infrared (FTIR) spectroscopy confirmed that the furfural content improved water resistance of the lignin-based adhesive; this improvement was due to the formation of new chemical bonds between furfural and lignin to construct a dense crosslinked network structure. In addition, the decrease in viscosity and the increase in solid content enabled the adhesive to better penetrate into the wood porous structure, showing stronger adhesion. Therefore, the LPFF adhesive has superior water resistance, high strength, and good thermal stability; thus, it has a great potential for industrial applications.
- Published
- 2020
757. Highly Thermal Stable Phenolic Resin Based on Double-Decker-Shaped POSS Nanocomposites for Supercapacitors
- Author
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Shiao-Wei Kuo, Wei-Cheng Chen, and Yuan-Tzu Liu
- Subjects
Thermogravimetric analysis ,supercapacitors ,Materials science ,Nanocomposite ,Polymers and Plastics ,Hydrosilylation ,Thermal decomposition ,General Chemistry ,hydrogen bonding ,Article ,Silsesquioxane ,law.invention ,lcsh:QD241-441 ,chemistry.chemical_compound ,lcsh:Organic chemistry ,X-ray photoelectron spectroscopy ,Chemical engineering ,chemistry ,law ,Calcination ,phenolic resin ,Fourier transform infrared spectroscopy ,POSS - Abstract
In this study we incorporated various amounts of a double-decker silsesquioxane (DDSQ) into phenolic/DDSQ hybrids, which we prepared from a bifunctionalized phenolic DDSQ derivative (DDSQ-4OH), phenol, and CH2O under basic conditions (with DDSQ-4OH itself prepared through hydrosilylation of nadic anhydride with DDSQ and subsequent reaction with 4-aminophenol). We characterized these phenolic/DDSQ hybrids using Fourier transform infrared spectroscopy, 1H, 13C, and 29Si nuclear magnetic resonance spectroscopy, X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis. The thermal decomposition temperature and char yield both increased significantly upon increasing the DDSQ content, with the DDSQ units providing an inorganic protection layer on the phenolic surface, as confirmed through XPS analyses. We obtained carbon/DDSQ hybrids from the phenolic/DDSQ hybrids after thermal curing and calcination at 900 °, C, these carbon/DDSQ hybrids displayed electrochemical properties superior to those of previously reported counterparts.
- Published
- 2020
758. A Novel Phenolic Foam-Derived Magnetic Carbon Foam Treated as Adsorbent for Rhodamine B: Characterization and Adsorption Kinetics
- Author
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Ru Li, Yao Zhang, Zhichao Lou, Yanjun Li, and Qiuyi Wang
- Subjects
Materials science ,magnetic ,General Chemical Engineering ,Carbon nanofoam ,Kinetics ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Reaction rate constant ,Adsorption ,lcsh:QD901-999 ,Rhodamine B ,General Materials Science ,phenolic resin ,Porosity ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Chemical engineering ,chemistry ,adsorption ,kinetics ,Chemisorption ,lcsh:Crystallography ,carbon foam ,0210 nano-technology ,Pyrolysis - Abstract
In recent decades, dye wastewaters produced by dye-manufacturing and dye-consuming industries have become a growing water pollution problem. Herein, a novel phenolic foam-derived magnetic carbon foam is synthesized by in-situ pyrolysis of iron acetylacetonate (Fe(acac)3) containing phenolic resin and its corresponding application as an adsorbent for the removal of Rhodamine B from effluent is investigated. The characterization of the as-prepared adsorbent is carried out by SEM, EDS, XRD, XPS, VSM, FT-IR, Raman, and BET. The magnetic carbon foam is observed to consist of a CFe15.1/C matrix modified with &alpha, Fe/Fe3C/Fe2O3 composites, possessing a 3D porous architecture formed by inter-connected cells with diameters of 50&ndash, 200 &mu, m and narrow ligaments with thicknesses of ~20 &mu, m. Experimental tests demonstrate that the equilibrium of adsorption behavior of Rhodamine B onto the obtained adsorbent can be reached within 40 min and the corresponding maximum adsorption capacity is 258.03 mg/g. The effects of contact time and adsorbent dosage on the adsorption performance are investigated. Besides, four models are introduced to fit the experimental data to evaluate the adsorption kinetics. The overall rate constant is determined by the chemisorption process, according to the pseudo-second order adsorption kinetics mechanism. Besides, the pH effect on RhB adsorption onto magnetic carbon foam is investigated, with the pH values varying from 3 to 10. The above results prove the application prospect of magnetic carbon foam prepared in this work in dye wastewater treatment.
- Published
- 2020
759. Study of Rheological Properties of ISOCURE® LF-305/904 G Binder System.
- Author
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Bakhtiyarov, Sayavur I. and Overfelt, Ruel A.
- Abstract
Viscous and thermal properties of a phenolic resin (Part I) and a polymeric isocyanate (Part II), and their blends were investigated by using rotational viscometry. The elastic properties of the blends were investigated by means of a jet thrust technique, using a straight tube. The theological and thermal properties of the blends were dependent on the blend composition. Although both materials are Newtonian liquids, their blends exhibit non-Newtonian liquid flow behavior and elasticity. A thermo-reaction has been observed and investigated after mixing the two parts. [ABSTRACT FROM PUBLISHER]
- Published
- 1997
- Full Text
- View/download PDF
760. Study of phenolic resin/EVA blends by thermal analysis.
- Author
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Mothé, C. and Tavares, M.
- Abstract
The properties of polymeric blends originate from the synergistic association of their components. In this investigation, phenolic resins obtained by the reaction of cashew-nut shell liquid (CNSL) and aldehyde are used in several applications. Mixtures of CNSL with industrial reject ethylene-co-vinyl acetate (EVA reject) were prepared with an EVA reject content up to 70%. The thermal compatibility and stability were evaluated by means of thermogravimetry (TG), derivative thermogravimetry (DTG) and differential scanning calorimetry (DSC). For blends containing a high percentage of EVA reject, the TG curves clearly show two decomposition stages, one at 350‡C and the other at 450‡C (onset 467‡C). The DIG curves of the blend containing 70% CNSL exhibit decomposition at 240‡C. The DSC curves show that the samples containing a high percentage of EVA reject are incompatible, with T
g values around −30‡C. [ABSTRACT FROM AUTHOR]- Published
- 1997
- Full Text
- View/download PDF
761. Respiratory morbidity in workers exposed to dust containing phenolic resin.
- Author
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Sparks, Patricia and Peters, John
- Abstract
Seventy-three men and women exposed to phenolic resin dust and/or processed cotton dust in a factory producing sound-deadening material were studied cross-sectionally. There was a statistically significant acute drop in FEV and FVC over the shift in garnett-line workers exposed to dust containing phenolic resin. Pickers, exposed to processed cotton dust only, did not show a significant drop in FEV and FVC over the work shift. Thirty-five percent of the workers that had smoked cigarettes and had worked in the plant 5 years or more had an FEV less than 80% of predicted. This finding was not entirely explained by duration of cigarette smoking. Multiple regression analysis revealed that the longer the duration of exposure, the lower the ratio of FEV to FVC. Respiratory symptoms were related to current cigarette smoking but not to duration of employment. The study suggests that exposure to dust containing phenolic resin had both acute and chronic effects on pulmonary function. [ABSTRACT FROM AUTHOR]
- Published
- 1980
- Full Text
- View/download PDF
762. Synthesis of phenolic resol resins using cornstalk-derived bio-oil produced by direct liquefaction in hot-compressed phenol–water.
- Author
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Wang, Mingcun, Leitch, Mathew, and Xu, Chunbao Charles
- Subjects
PHENOLIC resins ,BIOMASS ,ORGANIC synthesis ,POWDERS ,CORNSTALKS ,VEGETABLE oils ,OLIGOMERS ,LIGNINS - Abstract
Abstract: For the synthesis of biomass-based resol resins, cornstalk powders were liquefied in a hot-compressed phenol–water (1:4, wt./wt.) medium at 300–350°C. It was observed that essentially no phenol was reacted with the cornstalk degradation intermediates during the liquefaction process. The cornstalk-derived bio-oils contained oligomers of phenol and substituted phenols, originated primarily from the lignin component of the cornstalk feedstock. Using the cornstalk-derived bio-oils, resol resins were readily synthesized under the catalysis of sodium hydroxide. The biomass-derived resol resins were brown viscous liquids, possessing broad molecular weight distributions. In comparison with those of a conventional phenol resol resin, the properties of the bio-based resins were characterized by GPC, FTIR, DSC and TGA. The as-synthesized bio-oil resol resin exhibited typical properties of a thermosetting phenol–formaldehyde resin, e.g., exothermic curing temperatures at about 150–160°C, and an acceptable residual carbon yield of ca 56% at 700°C for the cured material. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
763. Synergistic Effects of Aluminum Diethylphosphinate and Melamine on Improving the Flame Retardancy of Phenolic Resin
- Author
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Juncheng Jiang, Wenjuan Li, Yanming Ding, Ru Zhou, and Jingjing Mu
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,Combustion ,lcsh:Technology ,01 natural sciences ,Article ,Limiting oxygen index ,chemistry.chemical_compound ,melamine ,Cone calorimeter ,General Materials Science ,Thermal stability ,phenolic resin ,Fourier transform infrared spectroscopy ,lcsh:Microscopy ,lcsh:QC120-168.85 ,lcsh:QH201-278.5 ,lcsh:T ,aluminum diethylphosphinate ,Thermal decomposition ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,lcsh:TA1-2040 ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,lcsh:Engineering (General). Civil engineering (General) ,0210 nano-technology ,Melamine ,lcsh:TK1-9971 ,flame retardancy ,Nuclear chemistry ,Fire retardant - Abstract
A series of novel flame retardants (aluminum diethylphosphinate and melamine) were used to improve the fire performance of phenolic resin. Fourier transform infrared spectroscopy (FTIR) was used to characterize the modification results. Thermo-gravimetric analysis (TGA) was used to study the thermal decomposition of phenolic resin system, and the flame retardancy of phenolic resin system was tested by vertical combustion test (UL-94) and limiting oxygen index (LOI). The combustion properties of modified phenolic resin were further tested with a cone calorimeter(CCT). Finally, the structure of carbon residue layer was measured by scanning electron microscopy (SEM). The results show that with the introduction of 10 wt % aluminum diethylphosphinate in phenolic resin, the LOI reaches 33.1%, residual carbon content increase to 55%. The heat release rate (HRR) decreased to 245.6 kW/m2, and the total heat release (THR) decreased to 58.6 MJ/m2. By adding 10 wt % aluminum diethylphosphinate and 3 wt % melamine, the flame retardancy of the modified resin can pass UL-94 V-0 flame retardant grade, LOI reaches 34.6%, residual carbon content increase to 59.5%. The HRR decreases to 196.2 kW/m2 at 196 s, relatively pure phenolic resin decreased by 35.5%, and THR decreased to 51 MJ/m2. Compared with pure phenolic resin, the heat release rate and total heat release of modified phenolic resin decreased significantly. This suggests that aluminum diethylphosphinate and melamine play a nitrogen-phosphorus synergistic effect in the phenolic resin, which improves the thermal stability and flame retardancy of the phenolic resin.
- Published
- 2019
764. Étude du comportement au feu de matériaux composites destinés à des applications aéronautiques : expériences et Modélisations
- Author
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Grange, Nathan, Laboratoire pluridisciplinaire de recherche en ingénierie des systèmes, mécanique et énergétique (PRISME), Université d'Orléans (UO)-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Institut National des Sciences Appliquées - Centre Val de Loire, Khaled Chetehouna, and Nicolas Gascoin
- Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other ,Phenolic resin ,Composites materials ,Feu ,Dégradation thermique ,Fibres de carbone ,Fire ,Résine PEKK ,Matériaux composites ,Simulation numérique ,Thermal degradation ,Pyrolyse ,Numerical simulations ,Carbon fiber ,Pekk resin ,Résine phénolique ,Pyrolysis - Abstract
Since the beginning of aeronautics, fire has been one of the first identified risks. However, the latter is still today the source of accidents, often fatal, lack of outcome when it intervenes in flight. At the same time, the need to reduce the mass of current aircraft, to limit operating costs, has made the use of composite materials, particularly fire-resistant, essential. In order to validate the fire performance of these materials, it is therefore necessary to certify their performance when subjected to fire. These tests represent a non-negligible cost during the development phases. The use of numerical simulations seems to be a good alternative in order to limit the number of trials. Nevertheless, the latter require a certain number of input parameters and a good knowledge of degradation phenomena. Thus in this work, the thermal degradation of two composite materials is studied, the thermoplastic carbon-PEKK and the thermosetting carbon-phenolic. The thermal and kinetic properties are first characterized on a small scale (ATG / DSC, DIL, diffusivity by flash method). Subsequently, these properties are used in the pyrolysis model that is validated on a medium scale using calorimeter cone degradation measurements. Finally, fire resistance tests are carried out using the NexGen burner of the experimental VESTA fire platform. In addition, the pyrolysis products are then evaluated during the degradation (Py-GC-MS) to determine the lower flammability limits and thus propose a classification of the materials studied.; Depuis les débuts de l’aéronautique, le feu fut l’un des premiers risques identifiés. Cependant, ce dernier est encore aujourd’hui la source d’accidents, souvent fatals, faute d’issue lorsqu’il intervient en vol. Dans le même temps, le besoin de réduire la masse des aéronefs actuels, pour limiter les coûts de fonctionnement, a rendu l’utilisation des matériaux composites, particulièrement réactifs au feu, indispensables. Afin de valider la performance au feu de ces matériaux, il est donc nécessaire de certifier leurs performances lorsqu’ils sont soumis au feu. Or ces essais représentent un coût non-négligeable pendant les phases de développement. L’utilisation des simulations numériques semble donc être une bonne alternative afin de limiter le nombre d’essais. Néanmoins ces dernières nécessitent un certain nombre de paramètres d’entrée et une bonne connaissance des phénomènes de dégradation. Ainsi dans ce travail, la dégradation thermique de deux matériaux composite est étudiée, le thermoplastique carbone-PEKK et le thermodurcissable carbone-phénolique. Les propriétés thermiques et cinétiques, indispensables pour la modélisation numérique du comportement au feu des matériaux, sont dans un premier temps caractérisées à petite échelle (ATG/DSC, DIL, diffusivité par méthode flash). Par la suite, ces propriétés sont utilisées dans le modèle de pyrolyse qui est validé à moyenne échelle, à l’aide de mesures de dégradation au cône calorimètre. Enfin, des essais de résistance au feu sont réalisés afin de valider les simulations numériques à grande échelle à l’aide du brûleur NexGen de la plateforme expérimental feux VESTA. De plus, les produits de pyrolyse sont évalués au cours de la dégradation (Py-GC-MS) pour déterminer les limites inférieures d’inflammabilité en fonction de la température et ainsi proposer une classification des matériaux étudiés.
- Published
- 2018
765. Study of the fire behavior of composite materials used for aeronautical applications: Experiments and Modeling
- Author
-
Grange, Nathan, Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA), Laboratoire pluridisciplinaire de recherche en ingénierie des systèmes, mécanique et énergétique (PRISME), Université d'Orléans (UO)-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), CIFRE, INSA Centre Val de Loire, Khaled Chetehouna, Nicolas gascoin, STAR, ABES, and GRANGE, Nathan
- Subjects
Composites materials ,feu ,[SPI.MECA.MEFL] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,[SPI.MAT] Engineering Sciences [physics]/Materials ,[SPI.MAT]Engineering Sciences [physics]/Materials ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,numerical simulations ,résine phénolique ,Carbon fibers ,phenolic resin ,thermal degradation ,PEKK resin ,[SPI.MECA.THER] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Thermics [physics.class-ph] ,[SPI.OTHER] Engineering Sciences [physics]/Other ,[SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment ,résine PEKK ,simulation numérique ,[SPI.FLUID] Engineering Sciences [physics]/Reactive fluid environment ,Composite materials ,pyrolysis ,fibres de carbone ,dégradation thermique ,pyrolyse ,Matériaux composites ,[SPI.MECA.THER]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Thermics [physics.class-ph] ,Carbon fiber ,fire - Abstract
Since the beginning of aeronautics, fire has been one of the first identified risks. However, the latter is still today the source of accidents, often fatal, lack of outcome when it intervenes in flight. At the same time, the need to reduce the mass of current aircraft, to limit operating costs, has made the use of composite materials, particularly fire-resistant, essential. In order to validate the fire performance of these materials, it is therefore necessary to certify their performance when subjected to fire. These tests represent a non-negligible cost during the development phases. The use of numerical simulations seems to be a good alternative in order to limit the number of trials. Nevertheless, the latter require a certain number of input parameters and a good knowledge of degradation phenomena. Thus in this work, the thermal degradation of two composite materials is studied, the thermoplastic carbon-PEKK and the thermosetting carbon-phenolic. The thermal and kinetic properties are first characterized on a small scale (ATG / DSC, DIL, diffusivity by flash method). Subsequently, these properties are used in the pyrolysis model that is validated on a medium scale using calorimeter cone degradation measurements. Finally, fire resistance tests are carried out using the NexGen burner of the experimental VESTA fire platform. In addition, the pyrolysis products are then evaluated during the degradation (Py-GC-MS) to determine the lower flammability limits and thus propose a classification of the materials studied., Depuis les débuts de l’aéronautique, le feu fut l’un des premiers risques identifiés. Cependant, ce dernier est encore aujourd’hui la source d’accidents, souvent fatals, faute d’issue lorsqu’il intervient en vol. Dans le même temps, le besoin de réduire la masse des aéronefs actuels, pour limiter les coûts de fonctionnement, a rendu l’utilisation des matériaux composites, particulièrement réactifs au feu, indispensables. Afin de valider la performance au feu de ces matériaux, il est donc nécessaire de certifier leurs performances lorsqu’ils sont soumis au feu. Or ces essais représentent un coût non-négligeable pendant les phases de développement. L’utilisation des simulations numériques semble donc être une bonne alternative afin de limiter le nombre d’essais. Néanmoins ces dernières nécessitent un certain nombre de paramètres d’entrée et une bonne connaissance des phénomènes de dégradation. Ainsi dans ce travail, la dégradation thermique de deux matériaux composite est étudiée, le thermoplastique carbone-PEKK et le thermodurcissable carbone-phénolique. Les propriétés thermiques et cinétiques, indispensables pour la modélisation numérique du comportement au feu des matériaux, sont dans un premier temps caractérisées à petite échelle (ATG/DSC, DIL, diffusivité par méthode flash). Par la suite, ces propriétés sont utilisées dans le modèle de pyrolyse qui est validé à moyenne échelle, à l’aide de mesures de dégradation au cône calorimètre. Enfin, des essais de résistance au feu sont réalisés afin de valider les simulations numériques à grande échelle à l’aide du brûleur NexGen de la plateforme expérimental feux VESTA. De plus, les produits de pyrolyse sont évalués au cours de la dégradation (Py-GC-MS) pour déterminer les limites inférieures d’inflammabilité en fonction de la température et ainsi proposer une classification des matériaux étudiés.
- Published
- 2018
766. Substrate Effect on Carbon/Ceramic Mixed Matrix Membrane Prepared by a Vacuum-Assisted Method for Desalination
- Author
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João C. Diniz da Costa, Julius Motuzas, Greg Birkett, Yingjun Song, David Wang, and Simon Smart
- Subjects
Materials science ,mixed matrix membrane ,ceramic substrate ,phenolic resin ,vacuum impregnation ,desalination ,chemistry.chemical_element ,Bioengineering ,02 engineering and technology ,engineering.material ,lcsh:Chemical technology ,Desalination ,lcsh:Chemistry ,020401 chemical engineering ,Coating ,Chemical Engineering (miscellaneous) ,lcsh:TP1-1185 ,Ceramic ,0204 chemical engineering ,Inert gas ,Carbonization ,Process Chemistry and Technology ,technology, industry, and agriculture ,Substrate (chemistry) ,021001 nanoscience & nanotechnology ,Membrane ,chemistry ,Chemical engineering ,lcsh:QD1-999 ,visual_art ,engineering ,visual_art.visual_art_medium ,0210 nano-technology ,Carbon - Abstract
This work investigates the effect of various membrane substrates and coating conditions on the formation of carbon/ceramic mixed matrix membranes for desalination application. The substrates were impregnated with phenolic resin via a vacuum-assisted method followed by carbonization under an inert gas. Substrates with pore sizes of 100 nm required a single impregnation step only, where short vacuum times (90%) and high water fluxes (up to 25 L m−2 h−1). The increase in water flux as a function of the vacuum time confirms the vacuum etching effect resulting from the vacuum-assisted method. Substrates with pore sizes of 140 nm required two impregnation steps. These pores were too large for the ceramic inter-particle space to be filled with phenolic resin via a single step. In the second impregnation step, increasing the concentration of the phenolic resin resulted in membranes with lower water fluxes. These results indicate that thicker films were formed by increasing the phenolic resin concentration. In the case of substrates with pores of 600 nm, these pores were too large and inter-particle space filling with phenolic resin was not attained.
- Published
- 2018
- Full Text
- View/download PDF
767. Preparation and Characterization of Carbon Foam Derived from Fine Coal and Phenolic Resin
- Author
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Komar Sutriah, Dodi Irwandi, Muhammad Khotib, and Zainal Alim Mas’ud
- Subjects
business.industry ,Scanning electron microscope ,Chemistry ,Carbon nanofoam ,insulation index ,General Chemistry ,Microstructure ,Compressive strength ,Thermal insulation ,thermal insulation ,Composition (visual arts) ,Coal ,phenolic resin ,Composite material ,Porosity ,business ,carbon foam ,QD1-999 ,fine coal - Abstract
Carbon foam from fine coal and phenolic resin mixture had been prepared by heating in nitrogen atmosphere. The composition of fine coal in a mixture was 30, 35, 40, 45 and 50%. Physical and mechanical characters of carbon foam that were determined from each of these compositions were density, porosity, compressive strength, and oxidation resistance and thermal insulation. Microstructure was observed by scanning electron microscope (SEM). Thermal insulation was tested using an insulation index approach with Styrofoam for comparison. The result showed that the density and compressive strength were proportional to the composition, otherwise, the porosity. Oxidation resistance that was up to 45% composition still showed proportional value. Microstructure observations showed an irregular distribution of pore and uninform diameter. Insulation index of 34 to 50 °C showed almost the same values of all compositions and greater than styrofoam up to 50-150% which mean carbon foam had a better thermal insulation properties than styrofoam.
- Published
- 2018
768. Valorization of cardanol and lipidic acids and aldehydes in the field of polymer materials
- Author
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Briou, Benoît, STAR, ABES, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Université Montpellier, Sylvain Caillol, and Vincent Lapinte
- Subjects
Cardanol ,Polyurethane ,Bio-Sourcé ,Vegetable oil ,Bio-Based ,[CHIM.OTHE] Chemical Sciences/Other ,Phenolic resin ,Huile végétale ,[CHIM.OTHE]Chemical Sciences/Other ,Plastifiant PVC ,PVC Plasticizer ,Résine phénolique ,Polyuréthane - Abstract
One of the major challenges in the field of polymers is the substitution of oil-based molecules for the development of monomers, polymers and polymer additives. The topic of this thesis is focused on the valorization of bio-sourced molecules and particularly, cardanol and vegetable oil derivatives. Since the scope of polymers is broad, we have chosen to focus on the following three major issues.At first, we were interested in the plasticization of PVC, which is most often carried out by phthalates, a family of oil-based esters strongly suspected to be endocrine disruptors. Alternative additives were thus synthesized by simple chemical reactions from cardanol and fatty esters. Good thermal stabilities and satisfactory plasticizing properties were obtained. Finally, toxicity and ecotoxicity tests have demonstrated the absence of a disruptive impact on the secretion of sex hormones and the non-toxicity towards the environment of these bio-sourced plasticizers.In a second step, we were interested in the chemistry of phenolic resins usually prepared from phenol and formaldehyde, two molecules classified as CMR substances. Thus, a bio-sourced phenol, cardanol, and a bio-sourced aldehyde, nonanal, were reacted to reach flexible phenolic resins. This peculiar property is the result of internal plasticization of the pendant lipid chains within the polymer network. By this example, the interest of vegetable oil derivatives for the production of flexible materials was demonstrated. Finally, a compromise between the flexibility of phenolic resins and their chemical and thermal resistances was reached.Finally, we turned to the development of crosslinked polyurethanes from a fatty ester, a fatty diester and a triglyceride exhibiting alpha-hydroxyketone functions (collaboration with the CASYEN team of the ICBMS). The contribution of the alpha-ketone function on the reactivity of the related to the isocyanate reagent is only modest compared to isolated alcohol type derivatives (castor oil) and alcohol associated with another alcohol function ( triglyceride 1,2-diol). Nevertheless, the presence of intramolecular interactions from ketone groups made possible to enhance the thermal stability of the PU materials and to develop flexible crosslinked PUs by internal plasticization, as in the case of phenolic resins.This thesis brings out the advantages provided by the use of lipid phenols such as cardanol and fatty chains for the improvement of thermal stability and flexibility of polymer materials., L’un des défis majeurs dans le domaine des polymères est la substitution des molécules pétro-sourcées en vue de l’élaboration de monomères, polymères et d'additifs pour polymères. Le travail de cette thèse s’axe sur la valorisation de molécules bio-sourcées et plus particulièrement, du cardanol et de dérivés d'huiles végétales. Le champ d’application des polymères étant large, nous avons choisi de nous centrer sur trois grandes problématiques.Dans un premier temps, nous nous sommes intéressés à la plastification du PVC qui, actuellement, est majoritairement réalisée par des phtalates, famille d’esters pétro-sourcés vivement suspectés d’être des perturbateurs endocriniens. Des additifs de substitution ont ainsi été synthétisés par une chimie simple à partir du cardanol et d’esters gras. Des stabilités thermiques et des propriétés plastifiantes très satisfaisantes ont été obtenues. Enfin, des tests de toxicité et d’écotoxicité ont démontré l’absence d'impact perturbateur sur la sécrétion d'hormones sexuelles et la non toxicité vis-à-vis de l'environnement de ces plastifiants bio-sourcés.Dans un second temps, nous avons revisité la chimie des résines phénoplastes habituellement préparées à partir du phénol et du formaldéhyde, deux molécules classées CMR. Nous avons adapté cette chimie robuste à un phénol bio-sourcé, le cardanol, et à un aldéhyde bio-sourcé, le nonanal, pour obtenir des résines phénoliques souples. Cette propriété recherchée est le résultat d’une plastification interne des chaines lipidiques pendantes au sein du réseau polymère. Par cet exemple, l’intérêt des dérivés d’huiles végétales pour l’élaboration de matériaux souples a été démontré. Un compromis entre la souplesse des résines phénoliques et leurs résistances chimique et thermique a été atteint.Enfin, nous nous sommes tournés vers l’élaboration de polyuréthanes réticulés à partir d’un ester gras, d’un diester gras et d’un triglycéride porteurs de fonctions alpha-hydroxycétone (collaboration avec l’équipe CASYEN de l’ICBMS). L’apport de la fonction alpha-cétone sur la réactivité du polyol vis-à-vis du réactif isocyanate n’est que modeste par rapport à des dérivés présentant un groupement alcool isolé sur la chaine (huile de ricin) et alcool associé à une autre fonction alcool (triglycéride 1,2-diol). Néanmoins, la présence d’interactions intramoléculaires provenant des groupements cétone a permis d’exacerber la stabilité thermique des matériaux PU et d’élaborer des PU réticulés souples par plastification interne comme dans le cas des résines phénoliques.Cette thèse a ainsi démontré l’apport des phénols lipidiques tels que le cardanol et des chaines grasses dans l’amélioration de la stabilité thermique et de la souplesse au sein de matériaux polymères.
- Published
- 2018
769. New SMC Materials for Small Electrical Machine With Very Good Mechanical Properties
- Author
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Fausto Franchini, Luca Ferraris, Marco Actis Grande, and Emir Poskovic
- Subjects
Materials science ,Mixing (process engineering) ,02 engineering and technology ,mechanical properties ,01 natural sciences ,Industrial and Manufacturing Engineering ,Iron powder ,law.invention ,epoxy resin ,Electric machines ,magnetic characterization ,phenolic resin ,soft magnetic composites (SMC) ,Control and Systems Engineering ,Electrical and Electronic Engineering ,law ,0103 physical sciences ,Lamination ,0202 electrical engineering, electronic engineering, information engineering ,Composite material ,010302 applied physics ,020208 electrical & electronic engineering ,Epoxy ,Magnetic flux ,Molding (decorative) ,visual_art ,visual_art.visual_art_medium ,Realization (systems) - Abstract
A new technology may be proposed for the realization of the magnetic parts of electromechanical devices, mainly for small electric machines. Such a technology provides the substitution of the traditional magnetic sheets with parts obtained by molding special magnetic powders [soft magnetic composites (SMC)]. The advantages may be constituted not only by economical reasons, but mostly by the possibility to realize parts having shapes otherwise impossible with the traditional lamination. Some commercial products are available in the market as “ready to press” powders, but their mechanical properties are in general not sufficient. To investigate the possibility to obtain good mechanical properties maintaining the magnetic characteristics of a selected commercial insulated iron powder compound, the authors have conducted a research activity based on the use of special iron powders and a selected epoxy resin as binder. The paper describes the activity carried out for the realization of SMC by mixing iron powders and Epoxy resin with different binder percentages and molding pressures. The obtained results have to be considered very satisfactory and suggest to continue the research argument to explore the possibilities of further improvements.
- Published
- 2018
770. Innovative Soft Magnetic Composite Materials: Evaluation of magnetic and mechanical properties
- Author
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Fausto Franchini, Emir Poskovic, Marco Actis Grande, Róbert Bidulský, and Luca Ferraris
- Subjects
Environmental Engineering ,Materials science ,Magnetic composite ,Aerospace Engineering ,02 engineering and technology ,epoxy resin ,magnetic characterisation ,mechanical properties ,phenolic resin ,powder metallurgy (PM) ,Soft Magnetic Composites (SMC) ,01 natural sciences ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,Electrical and Electronic Engineering ,Composite material ,Civil and Structural Engineering ,010302 applied physics ,Mechanical Engineering ,020208 electrical & electronic engineering ,Epoxy ,Engineering (General). Civil engineering (General) ,visual_art ,visual_art.visual_art_medium ,TA1-2040 - Abstract
Electrical machines cover a very wide range of applications in many industrials sectors and the research to improve the performance of those applications is recently leading to the development of new solutions. Those devices are generally equipped with magnetic circuits made of laminated ferromagnetic steel, but in the last decade, new magnetic materials have been developed to realise magnetic circuits: Soft Magnetic Composites (SMC). The Authors have investigated SMCs with organic layer obtained through the adoption of phenolic and epoxy resins; in previous research activities several mixture compositions have been produced and analysed with different percentages of binder and compacting pressures. Promising results regarding magnetic and mechanical performances have been obtained using a very low binder content. The paper aims to investigate the lower limit of the binder to be used, still keeping good mechanical properties. Appropriate magnetic tests have been performed on toroidal specimens: good magnetic characteristics have been obtained, maintaining on the other side proper mechanical strength.
- Published
- 2018
771. A Different Approach to Rare-Earth Magnet Recycling
- Author
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Emir Poskovic, Luca Ferraris, Enrico Pallavicini, Fausto Franchini, and Marco Actis Grande
- Subjects
Materials science ,Hydrogen ,Permanent magnets ,rare earth ,020209 energy ,Rare-earth magnet ,chemistry.chemical_element ,Magnetosphere ,02 engineering and technology ,recycling ,Magnetic hysteresis ,Engineering physics ,Magnetic flux ,bonded magnets ,magnetic characterization ,mechanical grinding ,phenolic resin ,production process ,chemistry ,Mechanical Treatments ,Magnet ,0202 electrical engineering, electronic engineering, information engineering ,Realization (systems) - Abstract
Permanent magnets are used in countless applications. Rare earths availability is reduced, while the demand is continuously increasing, together with the prices. Many hydrogen-based methods of recycling NeFeB magnets have already been adopted and studied. Three alternative processes are here proposed, based only on mechanical treatments. The impact of the mechanical procedures is analyzed with reference to the magnetic characteristics and compared with a commercial powder typically adopted in bonded magnets realization.
- Published
- 2018
772. EFFECT OF GRANULOMETRY AND OXYGEN CONTENT ON SMC MAGNETIC PROPERTIES
- Author
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Fausto Franchini, Luca Ferraris, Marco Actis Grande, Emir Poskovic, and Róbert Bidulský
- Subjects
lcsh:TN1-997 ,Materials science ,Metals and Alloys ,iron losses ,soft magnetic composites ,Grain size ,law.invention ,Magnetic circuit ,powder metallurgy ,Iron losses ,Magnetic characterization ,Phenolic resin ,Powder metallurgy ,Soft magnetic composites ,2506 ,law ,Granulometry ,Magnet ,Lamination ,phenolic resin ,Composite material ,magnetic characterization ,Oxygen content ,Realization (systems) ,lcsh:Mining engineering. Metallurgy - Abstract
The interest around the adoption of Soft Magnetic Composite materials (SMC) in the realization of electric machines, or parts of electric machines, is continuously increasing. The main reason lies on the opportunity to realize magnetic circuits following a 3D design procedure, which is not allowed with the adoption of the traditional lamination sheets. This is not the only reason, as a lot of research is being carried out on the losses distribution in the magnetic material, particularly as function of the frequency. In this paper different iron powders have been analyzed to investigate the impact of the granulometry on the SMC performance; in particular the grain size and the oxygen content have been considered variable parameters. The materials, prepared, compacted and tested in our laboratories, have been characterized to obtain the magnetic characteristic and information about the iron losses.
- Published
- 2017
773. Phenolic Resin Dual-Use Stamps for Capillary Stamping and Decal Transfer Printing.
- Author
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Guo L, Klein J, Thien J, Philippi M, Haase M, Wollschläger J, and Steinhart M
- Abstract
We report an optimized two-step thermopolymerization process carried out in contact with micropatterned molds that yields porous phenolic resin dual-use stamps with topographically micropatterned contact surfaces. With these stamps, two different parallel additive substrate manufacturing methods can be executed: capillary stamping and decal transfer microlithography. Under moderate contact pressures, the porous phenolic resin stamps are used for nondestructive ink transfer to substrates by capillary stamping. Continuous ink supply through the pore systems to the contact surfaces of the porous phenolic resin stamps enables multiple successive stamp-substrate contacts for lithographic ink deposition under ambient conditions. No deterioration of the quality of the deposited pattern occurs, and no interruptions for ink replenishment are required. Under a high contact pressure, porous phenolic resin stamps are used for decal transfer printing. In this way, the tips of the stamps' contact elements are lithographically transferred to counterpart substrates. The granular nature of the phenolic resin facilitates the rupture of the contact elements upon stamp retraction. The deposited phenolic resin micropatterns characterized by abundance of exposed hydroxyl groups are used as generic anchoring sites for further application-specific functionalizations. As an example, we deposited phenolic resin micropatterns on quartz crystal microbalance resonators and further functionalized them with polyethylenimine for preconcentration sensing of humidity and gaseous formic acid. We envision that also preconcentration coatings for other sensing methods, such as attenuated total reflection infrared spectroscopy and surface plasmon resonance spectroscopy, are accessible by this functionalization algorithm.
- Published
- 2021
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774. Synthesis and Thermal Degradation Study of Polyhedral Oligomeric Silsesquioxane (POSS) Modified Phenolic Resin.
- Author
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Wang, Degang, Ding, Jie, Wang, Bing, Zhuang, Yingluo, and Huang, Zhixiong
- Subjects
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PHENOLIC resins , *MICHAEL reaction , *MONOMERS , *SILICONES , *INFRARED spectroscopy , *MASS spectrometry , *THERMOGRAVIMETRY - Abstract
In this paper, a new polyhedral oligomeric silsesquioxane containing a phenol group (POSS-Phenol) is prepared through the Michael addition reaction, which is added to the synthesis of phenolic resin as a functional monomer. Infrared spectroscopy (IR) is used to demonstrate the chemistry structure of the synthesized POSS modified phenolic resin. After introducing POSS into the resole, a comprehensive study is conducted to reveal the effects of POSS on the thermal degradation of phenolic resin. First, thermal degradation behaviors of neat phenolic resin and modified phenolic resin are carried out by thermogravimetric analysis (TGA). Then, the gas volatiles from thermal degradation are investigated by thermogravimetric mass spectrometry (TG-MS). Finally, the residues after thermal degradation are characterized by X-ray diffraction (XRD). The research indicates that POSS modified phenolic resin shows a better thermal stability than neat phenolic resin, especially at high temperatures under air atmosphere. On the one hand, the introduction of the POSS group can effectively improve the release temperature of oxygen containing volatiles. On the other hand, the POSS group forms silica at high temperatures under air, which can effectively inhibit the thermal oxidation of phenolic resin and make phenolic resin show a better high-temperature oxidation resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
775. In-depth understanding on the early stage of phenolic resin thermal pyrolysis through ReaxFF-molecular dynamics simulation.
- Author
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Xing, Xiaolong, Niu, Xiaoru, Liu, Yun, Yang, Changhong, Wang, Shujuan, Li, Yu, and Jing, Xinli
- Subjects
- *
PHENOLIC resins , *MOLECULAR force constants , *PYROLYSIS , *MOLECULAR dynamics , *SCISSION (Chemistry) , *PLANT polyphenols - Abstract
• The early pyrolysis of PR is clarified from the view of cleavage reaction. • The cleavage reaction of PR occurs beside (CR b) and on (CR o) the backbone. • The H• from CR b is the initial species, leading to the formation of H 2 and H 2 O. • The decreasing char yield is caused by the loss of the terminal phenol from CR o. Acquiring deep understanding of the pyrolysis process of phenolic resin (PR) and its mechanism is of pivotal importance to develop new applications. Herein, novolac resin (NR) is used as the structural model to investigate the pyrolysis mechanism by carrying out a series of reactive force field molecular dynamics simulations. The structural evolution of NR and the formation process of small molecular species at nine different kinds of NR analogous models are investigated. The results show that the early pyrolysis process of NR involves mainly two aspects: the cleavage reactions beside backbone (CR b) and on backbone (CR o). The hydrogen radical produced from the cleavage of the methylene C—H bond, which belong to the CR b process, is the initial species detected during the pyrolysis process, and leads to the formation of H 2 O and H 2. Besides, the C—C bond cleavage of the methylene bridge is predominant in the CR o process, which takes place with almost equal probability. It mainly results in the formation of phenols, diphenols, polyphenols, and cross-linked structures. The volatilization of the phenol compounds stripped from the terminal groups is a critical process to reduce the char yield of the PR. Moreover, the main small-molecule species detected during the early pyrolysis of NR are H 2 O, H 2, and CO, and the higher energy is necessary to generate CO than H 2 O and H 2. This work deepens the understanding of the PR pyrolysis mechanism and provides valuable insights to develop its applications. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
776. Designing of amino functionalized imprinted polymeric resin for enantio-separation of (±)-mandelic acid racemate.
- Author
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Alhawiti, Aliyah S., Monier, M., and Elsayed, Nadia H.
- Subjects
- *
AMIDE derivatives , *IMPRINTED polymers , *MOLECULAR imprinting , *BINDING sites , *SCANNING electron microscopy , *PHENOLIC resins , *RACEMIC mixtures , *RESOLUTION (Chemistry) - Abstract
S-Mandelic acid (MA) enantio-selective resinous material functionalized with –NH 2 groups has been developed and effectively utilized in chiral separation of (±)-MA racemate solution. S-MA has first combined with the polymerizable p- aminophenol and form the corresponding amide derivative, which was then polymerized with phenol/formalin using HCl as a catalyst. The stereo-selective –NH 2 functionalized binding sites were then generated within the resin upon the alkaline degradation of the amide linkages followed by acidic treatments that will expel the resin incorporated S-MA out of the polymeric material to get the S-MA imprinted polymer (S-MAPR). The synthesized S-MA chiral amide derivative along with the developed polymeric resin was investigated by various techniques including FTIR and NMR spectra that confirmed the executed chemical modifications. In addition, the morphological appearance of the obtained resins were observed using SEM images. Moreover, the S-MAPR resin was examined to optimize the enantio-selective separation conditions and the studies indicated that the adsorption reached the highest value at pH 7 and the maximum capacity was 243 ± 1 mg/g. In addition, the chiral separation of (±)-MA racemic solution was successfully executed by the S-MAPR separation column with 55% and 82% enantiomeric excess of R- and S-MA within both the initial loading and recovery eluant solutions, respectively. Unlabelled Image • Polymerizable S-mandelic acid-p-aminophenol amide derivative (S-MA-AP) was synthesized. • The prepared S-MA-AP was implemented in polymerization with phenol and formalin. • The S-mandelic acid enantiomer was extracted from the polymer matrix. • The selective performance of the prepared S-MAPR resin was evaluated to anticipate the optimum uptake conditions. • The polymeric resin was applied for chiral resolution of (±)-mandelic acid racemate. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
777. Effect of Organo-Modified Montmorillonite Nanoclay on Mechanical, Thermo-Mechanical, and Thermal Properties of Carbon Fiber-Reinforced Phenolic Composites.
- Author
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Pumchusak, Jantrawan, Thajina, Nonthawat, Keawsujai, Watcharakorn, Chaiwan, Pattarakamon, Tcherdyntsev, Victor, and Rybak, Andrzej
- Subjects
- *
FIBROUS composites , *THERMAL properties , *HEAT resistant materials , *MONTMORILLONITE , *CARBON fiber-reinforced plastics , *IMPACT strength - Abstract
This work aims to explore the effect of organo-modified montmorillonite nanoclay (O-MMT) on the mechanical, thermo-mechanical, and thermal properties of carbon fiber-reinforced phenolic composites (CFRP). CFRP at variable O-MMT contents (from 0 to 2.5 wt%) were prepared. The addition of 1.5 wt% O-MMT was found to give the heat resistant polymer composite optimum properties. Compared to the CFRP, the CFRP with 1.5 wt% O-MMT provided a higher tensile strength of 64 MPa (+20%), higher impact strength of 49 kJ/m2 (+51%), but a little lower bending strength of 162 MPa (−1%). The composite showed a 64% higher storage modulus at 30 °C of 6.4 GPa. It also could reserve its high modulus up to 145 °C. Moreover, it had a higher heat deflection temperature of 152 °C (+1%) and a higher thermal degradation temperature of 630 °C. This composite could maintain its mechanical properties at high temperature and was a good candidate for heat resistant material. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
778. Electrical Behavior of Carbon Fiber/Phenolic Composite during Pyrolysis
- Author
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Kledermon Garcia, Luiz Claudio Pardini, Christian Frederico de Avila Von Dollinger, and Williane Oliveira de Souza
- Subjects
Thermal shock ,four-probe method ,Materials science ,Mechanical Engineering ,Composite number ,Reinforced carbon–carbon ,Activation energy ,Condensed Matter Physics ,Microstructure ,pyrolysis ,activation energy ,Mechanics of Materials ,Electrical resistivity and conductivity ,TA401-492 ,Gravimetric analysis ,carbon carbon composites ,General Materials Science ,phenolic resin ,Composite material ,Pyrolysis ,Materials of engineering and construction. Mechanics of materials ,electrical resistivity - Abstract
Carbon fiber reinforced carbon (CFRC) composites, also called carbon/carbon (C/C) composites are materials with superior characteristics such as low density, good thermal shock resistance, high strength and low ablation under severe environments. Due to their properties, CFRC composites are ideal candidate in the high temperature fields. By pyrolysis process, carbon fiber phenolic resin composites are converted in C/C composites. The phenolic resin is a non-conductor (electrical resistivity of 1012Ω.m) and during heat treatment of carbon fiber phenolic resin composite, it is converted to a carbon matrix (a conductor). This conversion was accomplished by electrical resistivity measurements using four-probe method according to ASTM C611-98 with final electrical resistivity of 0.04 mΩ.m. Microstructure of carbon fiber phenolic resin composite was assessed by using optical microscopy and image analysis. Pore volume was evaluated and the results were compared with thermal gravimetric analyses. The values of activation energy (Ea) during pyrolysis were 1.153kJ.mol–1 and 10.860kJ.mol–1.
- Published
- 2015
779. Activated carbon production by co-carbonization of feathers using water-soluble phenolic resin under controlled graphitization
- Author
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Norio Iwashita, Seiji Kenjo, Yutaka Kawahara, Kazuyoshi Yamamoto, Goro Nishikawa, Noboru Ishibashi, and Hiroyuki Wakizaka
- Subjects
Graphitization degree ,animal structures ,Materials science ,Renewable Energy, Sustainability and the Environment ,Carbonization ,Phenolic resin ,food and beverages ,Liquefaction ,Industrial and Manufacturing Engineering ,Water soluble ,Co-carbonization ,Feather ,visual_art ,Yield (chemistry) ,visual_art.visual_art_medium ,medicine ,Organic chemistry ,General Materials Science ,Charcoal ,Waste Management and Disposal ,Activated carbons ,Activated carbon ,medicine.drug ,Nuclear chemistry - Abstract
We attempted to use feathers for the production of activated carbon (AC). A water-soluble resol-type phenolic resin was hybridized to prevent the liquefaction of the feathers and to control the graphitization degree of charcoal. The hybridization could effectively increase the yield of charcoal over 30% and maintained the graphitization degree at approximately 0.1, suitable for the production of AC. The Brunauer–Emmett–Teller (BET) surface area and the iodine-adsorption capacity of hybrid charcoal-based AC were 706 m 2 /g and 550 mg/g, respectively, which were 1.7-1.8 times greater than those of the feather-based AC at a similar activation level.
- Published
- 2015
- Full Text
- View/download PDF
780. Development of carbon fiber/phenolic resin prepregs modified with nanoclays
- Author
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Liliana Beatriz Manfredi, Exequiel Santos Rodriguez, Vera Alejandra Alvarez, Guadalupe Rivero, and Lucía Asaro
- Subjects
Recubrimientos y Películas ,Materials science ,Phenolic resin ,Carbon fibers ,INGENIERÍAS Y TECNOLOGÍAS ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Phenolic composite ,Curing kinetic ,Ingeniería de los Materiales ,Materials Chemistry ,Composite material ,Mechanical Engineering ,Nanoclays ,Composite materials ,021001 nanoscience & nanotechnology ,Prepreg ,0104 chemical sciences ,Mechanics of Materials ,visual_art ,Ceramics and Composites ,visual_art.visual_art_medium ,Carbon fiber ,0210 nano-technology - Abstract
This work is focused on the study of the main variables involved in the development of phenolic/carbon prepregs and how these variables are affected by the incorporation of nanoclays. For this, phenolic resin was obtained from phenol and formaldehyde, performing the reaction under basic conditions and with formaldehyde excess. Resin curing kinetics was studied by means of Fourier Transform Infrared Spectroscopy (FTIR) measurements. Organo-modified clay was added to the phenolic resin in order to evaluate their effect on the general performance of the material. Carbon fiber-phenolic resin and carbon fiber-clay modified phenolic resin prepregs were obtained by hand-layup and vacuum bagging. Prepregs were characterized in terms of fiber content, flexural stiffness and degree of tack. In both cases, intermediate fiber volume content, near to 50 %, was obtained. The addition of 5 wt. % of clay to the phenolic resin did not produce a significant change on the prepregs stiffness but increased the degree of tack, which implies that the incorporation of such particles was useful to enhance the prepregs properties. Composite materials were obtained by compression molding of the prepregs obtained, and were characterized by its fiber content, mechanical behavior with the three point bending test and its thermal degradation by thermogravimetry. High fiber content composites materials were obtained, near to 75 % by volume. However modified composites showed lower fiber content, which resulted in a decrease of the flexural modulus and strength. In relation to thermal degradation the addition of nanoclay did not change the behavior of the materials. Fil: Asaro, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Rivero, Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Manfredi, Liliana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Rodriguez, Exequiel Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
- Published
- 2015
781. Application of microcapsulation technology to the preparation of carbon foam
- Author
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Ke-zhi Li, Zhen-hai Shi, He-jun Li, Zhuo Tian and Chuang Wang
- Subjects
microcapsulation technology ,carbon foam ,phenolic resin ,graphitization ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Biotechnology ,TP248.13-248.65 - Abstract
Microcapsules were prepared by in situ polymerization and microcapsulation. Tetraethyl orthosilicate was used as the core material and phenolic resin was used as the wall material in an emulsion system of polyacrylic and tetraethyl orthosilicate. The obtained microcapsules were slowly heated such that the core material was released by evaporation, leaving hollow-core spheres. The spheres were mixed with a phenolic resin-derived binder and molded to obtain a carbon foam precursor, which was carbonized at 1100 °C under the protection of N2 gas and graphitized at 2300 °C under the protection of Ar gas. Thus, the carbon foam of hollow closed-shelled microspheres with a graphitic structure was prepared. The properties and structure of this foam were discussed.
- Published
- 2008
782. Controlled catalytic and thermal sequential pyrolysis and hydrolysis of phenolic resin containing waste streams to sequentially recover monomers and chemicals
- Author
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Evans, Robert [Lakewood, CO]
- Published
- 1992
783. A novel carbon thermal reduction approach to prepare recorded purity β-Ti3O5 compacts from titanium dioxide and phenolic resin.
- Author
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Yang, Shunshun, Zhang, Le, Ma, Yuelong, Sun, Bingheng, Shan, Yinshuang, Shi, Zedi, Zhou, Tianyuan, Wang, Yun, Selim, Farida A., Li, Yanbin, Li, Hongliang, and Chen, Hao
- Subjects
- *
PHENOLIC resins , *TITANIUM dioxide , *PYROLYTIC graphite , *REVERSIBLE phase transitions , *ELECTROCHEMICAL sensors , *RIETVELD refinement - Abstract
β-phase titanium pentoxide (β-Ti 3 O 5) has great potential applications in sensors, electrodes and laser devices, due to its unique phase-transforming behaviors. However, just this reversible phase transition behaviors between λ and β phases made its high purity preparation be challenging, and the high energy consumption of present industrialized method also limited the high-level applications of β-Ti 3 O 5. In this work, a novel carbothermal reduction method has been acquired to produce highly pure β-Ti 3 O 5 compacts from titanium dioxide "wrapped" by phenolic resin served as carbon source. Their phase and microstructure evolutions during the whole reaction process were systematically characterized under the assistance of Rietveld refinement and SEM images. The highly active pyrolytic carbon of phenolic resin could deposit on the surface of TiO 2 and this compacted state could promote the generated CO to accelerate the reaction process and decrease the addition of reductant, simultaneously. The reduction sequences were TiO 2 → Ti 4 O 7 → Ti 3 O 5 → Ti 2 O 3. The weight ratio of phenolic to precursor of 9.0% could achieve the pure β-Ti 3 O 5 as high as 98.06% under the calcination temperature of 1250 °C for 4 h. This work provided a novel and industrialized route to prepare β-Ti 3 O 5 for applications in sensor and electrode in electrochemical reactions. • A novel carbon thermal reduction for the high purity β-Ti 3 O 5. • Reduction mechanism of phenolic resin and phase evolution of TiO 2. • Carbothermal reduction for the low cost and high efficiency preparation of oxides. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
784. High-performance polyethylene separators for lithium-ion batteries modified by phenolic resin.
- Author
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Gu, Qian-Qian, Xue, Hong-Jin, Li, Zhan-Wei, Song, Jing-Chuan, and Sun, Zhao-Yan
- Subjects
- *
ULTRAHIGH molecular weight polyethylene , *PHENOLIC resins , *LITHIUM-ion batteries , *MACHINE separators , *POLYOLEFINS , *NEGATIVE electrode , *POLYSULFIDES - Abstract
In lithium-ion batteries, separator serves to isolate the positive and negative electrodes, as well as provide a free shuttle for Li-ion transport inside the battery. Commercial polyolefin separator has relatively higher thermal shrinkage and lower electrolyte wettability, which limits the application of batteries in extreme conditions. In this work, we prepared phenolic resin (AF) modified polyethylene (PE) composite separators by the process of immersion in situ reaction. The obtained PE@AF composite separator has lower thermal shrinkage and higher electrolyte wettability than pure PE separator. The shrinkage of our prepared PE@AF separator is only 6% when stored at 145 °C for 30 min, greatly smaller than the pure PE separator (more than 77%). Moreover, the ion conductivity of PE@AF composite separator increases from 0.206 mS cm−1 for the pure one to 0.604 mS cm−1. Apart from this, the Li/electrolyte-soaked PE@AF separator/LiFePO 4 battery exhibits a higher coulombic efficiency (96.7%) and discharge capacity retention rate (86.0%) after 450 cycles than the pure one (67.4% and 72.7%, respectively). Our results indicate that the AF coating plays a vital part in improving the thermal stability and electrochemical property of polyolefin separators. • The PE@AF separator was prepared via a facile one-pot immersion in situ reaction. • The PE@AF exhibits better heat stability and interfacial compatibility. • The battery exhibits higher coulombic efficiency and discharge capacity retention. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
785. One-pot depolymerization, demethylation and phenolation of lignin catalyzed by HBr under microwave irradiation for phenolic foam preparation.
- Author
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Gao, Cheng, Li, Ming, Zhu, Chenjie, Hu, Youqin, Shen, Tao, Li, Mengyu, Ji, Xingxiang, Lyu, Gaojin, and Zhuang, Wei
- Subjects
- *
LIGNINS , *LIGNIN structure , *DEPOLYMERIZATION , *DEMETHYLATION , *PHENOLIC resins , *FOAM , *DIFFERENTIAL scanning calorimetry - Abstract
High-value utilization of lignin is critical to improve the economic viability of integrated biorefineries. In this study, HBr was employed as a trifunctional catalyst to perform depolymerization, phenolation and demethylation of lignin in phenol to improve the reactivity of lignin and the obtained product was further directly used to prepare phenolic foams without purification. With the aid of microwave irradiation, a reduced reaction time and mild reaction conditions were achieved. The results showed that the phenolic hydroxyl content increased from 2.89 mmol/g to 5.90 mmol/g (increased by 104%) while the methoxyl group content dropped from the 4.75 mmol/g to 3.37 mmol/g (decreased by 30%) under the optimized conditions (10% HBr, 90 °C and 2 h). The structure changes of lignin were investigated by FT-IR, GPC, 1H, 31P, and 2D HSQC NMR analyses. Due to the enhanced activity of lignin, the activation energy and characteristic curing temperature of the modified lignin-based phenolic resin (103.27 kJ/mol, 130.1 °C) was markedly lower than that of the unmodified lignin-based phenolic resin (113.48 kJ/mol, 139.4 °C) according to differential scanning calorimetry (DSC) analysis. Further characterization of the modified lignin-based phenolic foam showed it has better thermal insulation and mechanical properties than that of unmodified lignin-based phenolic foam, which provides a value-added application of lignin as insulating foam material. Image 1 • Reactivity of lignin was improved by depolymerization, demethylation and phenolation catalyzed with HBr. • Phenolic hydroxyl content increased by 104%, while methoxyl group content decreased by 30%. • Activation energy of phenolic resin (103.27 kJ/mol) was lower than that of unmodified (113.48 kJ/mol). • Phenolic foam from modified lignin showed superior thermal insulation and mechanical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
786. Method of recovering hazardous waste from phenolic resin filters
- Published
- 1991
787. Synthesis and performance of LiFe x Mn1−x PO4/C as cathode material for lithium ion batteries
- Author
-
Liu, Xuewu / 刘学武, Qin, Xusong, Wang, Xiaojuan, Li, Xin, and Chen, Shen
- Published
- 2015
- Full Text
- View/download PDF
788. Large-Scale Preparation of Carbon Nanotubes via Catalytic Pyrolysis of Phenolic Resin at Low Temperature
- Author
-
Wang, Junkai, Deng, Xiangong, Zhang, Haijun, Cheng, Feng, Li, Faliang, and Zhang, Shaowei
- Published
- 2015
- Full Text
- View/download PDF
789. In situ reduction and functionalization of graphene oxide to improve the tribological behavior of a phenol formaldehyde composite coating
- Author
-
Yang, Mingming, Zhang, Zhaozhu, Zhu, Xiaotao, Men, Xuehu, and Ren, Guina
- Published
- 2015
- Full Text
- View/download PDF
790. Effect of Phenolic Resin on the Rheological and Morphological Characteristics of Styrene-Butadiene Rubber-Modified Asphalt.
- Author
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Cheng, Peifeng, Li, Yiming, and Zhang, Zhanming
- Subjects
- *
ASPHALT modifiers , *PHENOLIC resins , *ASPHALT , *FOURIER transform infrared spectroscopy , *GEL permeation chromatography , *POLYMER degradation , *STYRENE-butadiene rubber - Abstract
To improve the thermal-aging stability and rheological performance of styrene–butadiene rubber (SBR)-modified asphalt, phenolic resin (PF) was introduced in the process of preparing SBR-modified asphalt by melt blending. The effect of PF and SBR on the high and low-temperature rheological performance of the asphalt binder before and after aging was evaluated by a temperature and frequency sweep using a dynamic shear rheometer (DSR). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and fluorescence microscopy (FM) were used to further investigate the effect of PF and SBR on the thermal stability and morphological characteristics of the asphalt binder. The results showed that the addition of PF can enhance the high-temperature deformation resistance and short-term aging resistance of SBR-modified asphalt. Moreover, PF and SBR form an embedded network structure within the asphalt binder and alleviate the deterioration of the polymer during the aging process. Compared with SBR-modified asphalt, the chemical system of composite-modified asphalt is more stable, and it can remain stable with an aging time of less than 5 h. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
791. Synthesis of High-Water-Resistance Lignin-Phenol Resin Adhesive with Furfural as a Crosslinking Agent.
- Author
-
Zhang, Yufei, Li, Ning, Chen, Zhikang, Ding, Chen, Zheng, Qi, Xu, Jindi, and Meng, Qiulu
- Subjects
- *
FURFURAL , *RESIN adhesives , *NUCLEAR magnetic resonance , *CHEMICAL bonds , *INDUSTRIAL capacity , *SHEAR strength - Abstract
In this study, furfural was used as a crosslinking agent to enhance the water resistance of lignin-phenol-formaldehyde (LPF) resin. The effect of the furfural content on the physicochemical properties of the adhesives was explored, and the possible synthesis mechanism of the furfural-modified lignin-phenol-formaldehyde (LPFF) resin adhesives was investigated. Compared with the LPF adhesive, the LPFF adhesive with 15% furfural content and 50% lignin substituent exhibited outstanding properties in all considered aspects; it had a high wet shear strength (1.30 MPa), moderate solid content (54.51%), and low viscosity (128 mPa∙s), which were 38.0% higher, 3.6% higher, and 37.5% lower than those of the LPF adhesive. Analyses via nuclear magnetic resonance and Fourier transform infrared (FTIR) spectroscopy confirmed that the furfural content improved water resistance of the lignin-based adhesive; this improvement was due to the formation of new chemical bonds between furfural and lignin to construct a dense crosslinked network structure. In addition, the decrease in viscosity and the increase in solid content enabled the adhesive to better penetrate into the wood porous structure, showing stronger adhesion. Therefore, the LPFF adhesive has superior water resistance, high strength, and good thermal stability; thus, it has a great potential for industrial applications. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
792. Tailoring a Phenolic Resin Precursor by Facile Pre-oxidation Tactics to Realize a High-Initial-Coulombic-Efficiency Hard Carbon Anode for Sodium-Ion Batteries.
- Author
-
Zhang G, Zhang L, Ren Q, Yan L, Zhang F, Lv W, and Shi Z
- Abstract
As the leading anode material for sodium-ion batteries (SIBs), hard carbon (HC) still faces the puzzle of low initial Coulombic efficiency (ICE) in achieving commercialization. From the perspective of precursors, the low ICE has been attributed to the large specific surface area and porosity produced by the rapid decomposition of polymers during the carbonization. Therefore, increasing the cross-linking degree of precursors will be an effective shortcut to improve the ICE. Herein, a facile pre-oxidation tactic was successfully employed to tailor the cross-linking degree of phenolic resin precursors to precisely control the specific surface area of the obtained HC. As the pre-oxidation time is increased, the optimal HC with the lowest specific surface area shows an ICE elevated by 22.2% (from 62.5 to 84.7%) compared to the original pre-oxidation HC and delivers a high reversible capacity of 334.3 mAh g
-1 at 20 mA g-1 . Besides, the pre-oxidation also introduces abundant carbonyl groups, which increase the disorder degree of HC and supply abundant adsorption sites of Na+ , thus enhancing the rate performance. When matched with a layered O3-NaNi1/3 Fe1/3 Mn1/3 O2 cathode, the full cell achieves an energy density of ca. 256.2 Wh kg-1 with superior rate performance. This work sheds light on the positive effect of pre-oxidation in elevating the ICE of HC and provides effective guidance to achieve a high ICE for other HC materials.- Published
- 2021
- Full Text
- View/download PDF
793. Hydrophilic deep eutectic solvents modified phenolic resin as tailored adsorbent for the extraction and determination of levofloxacin and ciprofloxacin from milk.
- Author
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Ma W and Row KH
- Subjects
- Adsorption, Animals, Anti-Bacterial Agents analysis, Ciprofloxacin analysis, Hydrophobic and Hydrophilic Interactions, Levofloxacin analysis, Solid Phase Extraction methods, Solvents, Anti-Bacterial Agents isolation & purification, Ciprofloxacin isolation & purification, Food Contamination analysis, Formaldehyde chemistry, Levofloxacin isolation & purification, Milk chemistry, Phenols chemistry, Polymers chemistry
- Abstract
A reliable and efficient method for the simultaneous extraction and determination of antibiotics of ciprofloxacin and levofloxacin from milk was developed with solid phase extraction based on tailored adsorbent materials of deep eutectic solvents modified phenolic resin (DES-R-SPE). Six types of polyhydric alcohol-based hydrophilic DESs were prepared to modify the phenolic resin with the compositions of 3-aminophenol as a functional monomer, glyoxylic acid as a crosslinker, and polyethylene glycol 6000 as a porogen. And the prepared DES-Rs showed better extraction capacities for the target analytes than the unmodified phenolic resin because of more hydrogen bonding and electrostatic interactions supplied by DESs. The choline chloride-glycerol-based resin (DES
1 -R) with the highest adsorption amounts was selected and the adsorption behavior of it was studied with static adsorption and the dynamic adsorption performance; the adsorption process followed Freundlich isotherm (R2 ≥ 0.9337) and pseudo-second-order (R2 ≥ 0.9951). The present DES1 -R-SPE method showed good linear range from 0.5 to100 μg mL-1 (R2 ≥ 0.9998), good recoveries of spiked milk samples (LEV, 96.7%; CIP, 101.5%), and satisfied repeatability for intra-day and inter-day (LEV, RSD≤5.4%; CIP, RSD≤4.6%).- Published
- 2021
- Full Text
- View/download PDF
794. Aging Studies of Composite Alumina Carbon Molecular Sieve Membranes.
- Author
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Tanco, M.A. Llosa, Tanaka, D.A. Pacheco, Rodrigues, S.C., and Mendes, A.M.
- Published
- 2012
- Full Text
- View/download PDF
795. The influence of thermal expansion of unbonded foundry sands on the deformation of resin bonded cores
- Author
-
Svidró, Judit, Diószegi, Attila, Tóth, L., Svidró, József Tamás, Svidró, Judit, Diószegi, Attila, Tóth, L., and Svidró, József Tamás
- Abstract
Depending on the preparation and the applied materials, moulds and cores can be of high rigidity or can be flexible. Although, chemically bonded moulding materials have relatively good flexibility, their high temperature behaviour determines the dimensional accuracy, the stresses in the castings and can induce several casting defects, such as rattail, veining, etc. The phenomenon is based on two major effects: the thermal expansion of the unbonded foundry sands and the deformation of the sand mixtures. The main objective of the present work was to study the relationship between these two effects, and to improve the knowledge related to the thermo-mechanical interactions between the casting and the mould. Dilatometric analysis of unbonded sand samples were performed and compared to the results of hot distortion tests of moulding mixture specimens. The results showed, that the thermal expansion of foundry sand largely influences the hot distortion behaviour, but depending on the type of binder used.
- Published
- 2017
- Full Text
- View/download PDF
796. Innovative ablative fire resistant composites based on phenolic resins modified with mesoporous silica particles
- Author
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Exequiel Santos Rodriguez, Sergio Antonio Pellice, Raul Ariel Procaccini, Liliana Beatriz Manfredi, and Lucía Asaro
- Subjects
Materials science ,Recubrimientos y Películas ,Polymers and Plastics ,Scanning electron microscope ,ABLATIVE MATERIALS ,SILICA PARTICLES ,02 engineering and technology ,INGENIERÍAS Y TECNOLOGÍAS ,010402 general chemistry ,01 natural sciences ,chemistry.chemical_compound ,Ingeniería de los Materiales ,Ablative case ,Materials Chemistry ,COMPOSITE MATERIALS ,PHENOLIC RESIN ,Composite material ,Carbon black ,Dynamic mechanical analysis ,Mesoporous silica ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Tetraethyl orthosilicate ,purl.org/becyt/ford/2 [https] ,chemistry ,Mechanics of Materials ,Transmission electron microscopy ,THERMAL PROTECTION SYSTEM ,purl.org/becyt/ford/2.5 [https] ,0210 nano-technology ,Glass transition - Abstract
Mesoporous silica particles were used as reinforcement of a phenolic resin to develop new ablative materials. A resol type phenolic resin was filled with mesoporous silica particles synthesized from tetraethyl orthosilicate (TEOS). Samples of neat phenolic resin, phenolic resin reinforced with carbon black and with mesoporous silica particles (5 and 20 wt %), were obtained. The ablative properties of the materials were studied by the oxyacetylene torch test and the ablated samples were observed by scanning electron microscopy (SEM). The composites were also characterized by dynamic mechanical analysis and transmission electron microscopy (TEM). Results showed a stronger chemical interaction between silica particles and the phenolic resin, than carbon black, thus increasing the glass transition temperature and mechanical properties of the silica/resin composites. In addition, the samples with mesoporous silica particles achieved lower erosion rates and back-face temperatures than the others, becoming promising thermal protection materials for the aerospace industry. Fil: Asaro, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Manfredi, Liliana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Pellice, Sergio Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Procaccini, Raul Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Rodriguez, Exequiel Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
- Published
- 2017
797. Green Carbon Composite-Derived Polymer Resin and Waste Cotton Fibers for the Removal of Alizarin Red S Dye
- Author
-
Ichrak Ben Hariz, Cyril Vaulot, Camelia Matei Ghimbeu, Béchir Wanassi, Mejdi Jeguirim, Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
- Subjects
Control and Optimization ,Materials science ,anionic dye ,Composite number ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,010501 environmental sciences ,lcsh:Technology ,01 natural sciences ,Endothermic process ,Adsorption ,Desorption ,Specific surface area ,[CHIM]Chemical Sciences ,Fiber ,phenolic resin ,Electrical and Electronic Engineering ,Engineering (miscellaneous) ,0105 earth and related environmental sciences ,Chromatography ,lcsh:T ,Renewable Energy, Sustainability and the Environment ,Carbon nanofiber ,green precursor ,waste cotton ,adsorption ,021001 nanoscience & nanotechnology ,chemistry ,Chemical engineering ,0210 nano-technology ,Carbon ,Energy (miscellaneous) - Abstract
International audience; Phenolic resin and waste cotton fiber were investigated as green precursors for the successful synthesis using a soft template approach of a composite carbon with carbon nanofibers embedded in a porous carbon network with ordered and periodically pore structure. The optimal composite carbon (PhR/NC-1), exhibited a specific surface area of 394 m 2 ·g −1 with the existence of both microporosity and mesoporosity. PhR/NC-1 carbon was evaluated as an adsorbent of Alizarin Red S (ARS) dye in batch solution. Various operating conditions were examined and the maximum adsorption capacity of 104 mg·g −1 was achieved under the following conditions, i.e., T = 25 • C, pH = 3, contact time = 1440 min. The adsorption and desorption heat was assessed by flow micro-calorimetry (FMC), and the presence of both exothermic and endothermic peaks with different intensity was evidenced, meaning a partially reversible nature of ARS adsorption. A pseudo-second-order model proved to be the most suitable kinetic model to describe the ARS adsorption according to the linear regression factor. In addition, the best isotherm equilibrium has been achieved with a Freundlich model. The results show that the eco-friendly composite carbon derived from green phenolic resin mixed with waste cotton fibers improves the removal of ARS dye from textile effluents.
- Published
- 2017
798. Development of Phenolic Resin Based High Performance Brake Block Compound through Optimization of Different Ingredients
- Author
-
Ghosh, Prosenjit
- Subjects
Optimization of Different Ingredients ,Phenolic Resin ,CPC ,Railways ,Aramid Pulp ,Brake Block - Published
- 2017
799. Oxidation behavior at moderate temperature under dry and wet air of phenolic resin-derived carbon
- Author
-
X. Bertran, J. Dentzer, M-A Dourges, R. Gadiou, S. Fouquet, Georges Chollon, Francis Rebillat, Laboratoire des Composites Thermostructuraux (LCTS), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Snecma-SAFRAN group-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie et des Surfaces et Interfaces (ICSI), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS), Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Safran Ceramics, Institut de chimie des surfaces et interfaces de Mulhouse (ICSIM), Ecole Nationale Supérieure de Chimie de Mulhouse-Centre National de la Recherche Scientifique (CNRS), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
- Subjects
Thermogravimetric analysis ,Materials science ,Analytical chemistry ,Carbon materials ,chemistry.chemical_element ,Oxidation behavior ,02 engineering and technology ,010402 general chemistry ,Thermogravimetric Analyses ,01 natural sciences ,Isothermal process ,Chemical kinetics ,symbols.namesake ,X-ray photoelectron spectroscopy ,Organic chemistry ,Reaction Kinetics ,Physical and Theoretical Chemistry ,Instrumentation ,Phenolic Resin ,Structure ,[CHIM.MATE]Chemical Sciences/Material chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,chemistry ,13. Climate action ,symbols ,Limiting oxygen concentration ,0210 nano-technology ,Raman spectroscopy ,Pyrolysis ,Carbon - Abstract
International audience; The oxidation behavior of carbon materials has been investigated at temperatures less than 773 K using isothermal thermogravimetric analyses under dry and wet air. Bulk samples obtained by the pyrolysis of phenolic resin have been characterized using X-ray diffraction and elementary analysis. X-ray photoelectron spectroscopy and Raman spectroscopy have been performed to analyze the surface and subsurface. The carbon structure has a poor organization state and a gradient in the oxygen concentration and structure between the surface and the bulk is revealed. The material is more reactive under wet air than dry air in terms of oxidation rates as determined between 623 and 773 K. The apparent activation energies are respectively 122 ± 6 kJ/mol in dry air and 102 ± 6 kJ/mol in wet air.
- Published
- 2017
800. Impact of different nanoparticles on the thermal degradation kinetics of phenolic resin nanocomposites
- Author
-
David Alberto D'amico, Liliana Beatriz Manfredi, Exequiel Santos Rodriguez, Lucía Asaro, and Vera Alejandra Alvarez
- Subjects
Materials science ,Nanocomposite ,Recubrimientos y Películas ,Degradation kinetics ,Nano-filler ,Kinetic models ,Phenolic resin ,Nanoparticle ,02 engineering and technology ,INGENIERÍAS Y TECNOLOGÍAS ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Chemical engineering ,Ingeniería de los Materiales ,Thermal degradation ,Physical and Theoretical Chemistry ,Composite material ,0210 nano-technology ,Composites - Abstract
The effect of different contents of nano-fillers: carbon black (CB), bentonites (original (Bent) and modified with phosphonium salt (B-TBHP)) and commercial modified montmorillonite (C30B) on the thermal degradation of phenolic resin was studied by thermogravimetric analysis (TG). The obtained results strongly suggest that CB was the most effective filler in improving the thermal stability of the resol type phenolic matrix. The previous results were associated with the thermal stability of each filler but also with the compatibility between the matrix and the filler and the effect of filler incorporation on the crosslinking degree of the neat matrix. The profile of the apparent activation energy with the conversion of the thermal degradation process for the resol and the nanocomposites was obtained using three isoconversional methods: Friedman, KAS and Vyazovkin. The curves were correlated with the degradation steps of the phenolic resin observed by TG, showing a similar degradation mechanism for all the systems. By means of the method of invariant kinetic parameters (IKP), it was possible to estimate the preexponential factor and the activation energy to describe the degradation process of the resol and the nanocomposites in the thermal fragmentation zone, between 350 and 600 ºC. It was determined that the Sestak?Berggren model was the one that best describes the thermal degradation experimental data. Then, a comparison between the experimentally obtained and the simulated differential degradation curves shows that the resulting model was certainly accurate to predict the thermal degradation process of the resol and the nanocomposites. Fil: Asaro, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: D'amico, David Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Rodriguez, Exequiel Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Manfredi, Liliana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina
- Published
- 2017
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