Preparation of Poly(aniline-co-phenol) and Study Its Properties and Its Polymerization Kinetics Using Two Methods: UV-Vis and HPLC

2021 ◽  
Vol 43 (5) ◽  
pp. 505-505
Author(s):  
Juhaina Alghdir and Ahmad Falah Juhaina Alghdir and Ahmad Falah
Keyword(s):  
Transition Temperature ◽  
Reaction Order ◽  
Sem Analysis ◽  
304 Stainless Steel ◽  
Melting Transition ◽  
Gravimetric Analysis ◽  
Zero Order Reaction ◽  
Kinetics Of ◽  
Thermal Stability Of ◽  
Poly Aniline

The co-polymerization of polyaniline is one of the most important methods used to improve the electrical activity and thermal stability of polyaniline. Previously, electrochemical co-polymerization of phenol and aniline was performed on 304 stainless steel anodes. In this study, we present the co-polymerization of aniline and phenol chemically at laboratory temperature in an acidic medium with ammonium pyrosulfate as an oxidant. The Scanning Electron Microscopy (SEM) analysis of poly(aniline-co-phenol) sample shows a rough (non-smooth) surface with crystalline particles with microscopic diameters. We characterized the prepared polymer with DSC, DTA, and thermos gravimetric analysis (TGA). We found that the thermal decomposition of poly(aniline-co-phenol) was on six steps. The glass transition temperature of the co-polymer (Tg) was found at 863.89 and#176;C and the melting transition temperature was observed at 877.80 and#176;C. We studied the kinetics of Poly(aniline-co-phenol) using two methods: UV-Vis, HPLC. Then we determined the reaction order. It was found that the reaction was the zero-order reaction (n=0) in both previous two methods.

Study the Polymerization Kinetics of Polyaniline by UV-Vis and HPLC and Determination of the Thermodynamic Functions using Coats-Redfern Equation from TGA Curves

2021 ◽  
pp. 4117-4121
Author(s):  
Juhaina Alghdir ◽  
Ahmad Falah ◽  
Sameh Hamo
Keyword(s):  
Thermodynamic Functions ◽  
Reaction Order ◽  
Thermal Dissociation ◽  
Temporal Stability ◽  
Sem Analysis ◽  
Order Reaction ◽  
Zero Order Reaction ◽  
Mathematical Equations ◽  
Kinetics Of

This study includes the preparation of the polyaniline at the laboratory temperature in an acidic medium. The Scanning Electron Microscopy (SEM) analysis of Polyaniline shows smooth surface and uniform nanoparticles formation with diameters of 56.4 to 90 nm. The polymerization of polyaniline kinetics was studied with two methods: UV-Vis, HPLC. Then the polymerization of polyaniline reaction order was determined and it was the zero-order reaction (n=0) in both of the previous two methods. The study of thermal dissociation indicates the temporal stability of chemicals, and study the decomposition kinetics to determine the thermodynamic functions of material disintegration. There are many methods use mathematical equations applied to TGA to study this phenomenon. The thermodynamic functions of the prepared polymers such as (G*, S*, H*) were determined based on Coats-Redfern equation from TGA curves of the compounds at each step of the disintegration.

scholarly journals Development of Nervilia fordii Extract-Loaded Electrospun PVA/PVP Nanocomposite for Antioxidant Packaging

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1728
Author(s):  
Peng Wen ◽  
Teng-Gen Hu ◽  
Yan Wen ◽  
Ke-Er Li ◽  
Wei-Peng Qiu ◽  
...  
Keyword(s):  
Food Packaging ◽  
Thermo Gravimetric Analysis ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Poly Vinyl Alcohol ◽  
Total Phenolic ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
Phenolic And Flavonoid ◽  
Thermal Stability Of

An ethyl acetate extract from of Nervilia fordii (NFE) with considerable suppression activity on lipid peroxidation (LPO) was first obtained with total phenolic and flavonoid contents and anti-LPO activity (IC50) of 86.67 ± 2.5 mg GAE/g sample, 334.56 ± 4.7 mg RE/g extract and 0.307 mg/mL, respectively. In order to improve its stability and expand its application in antioxidant packaging, the nano-encapsulation of NFE within poly(vinyl alcohol) (PVA) and polyvinyl(pyrrolidone) (PVP) bio-composite film was then successfully developed using electrospinning. SEM analysis revealed that the NFE-loaded fibers exhibited similar morphology to the neat PVA/PVP fibers with a bead-free and smooth morphology. The encapsulation efficiency of NFE was higher than 90% and the encapsulated NFE still retained its antioxidant capacity. Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD) analysis confirmed the successful encapsulation of NFE into fibers and their compatibility, and the thermal stability of which was also improved due to the intermolecular interaction demonstrated by thermo gravimetric analysis (TGA). The ability to preserve the fish oil’s oxidation and extend its shelf-life was also demonstrated, suggesting the obtained PVA/PVP/NFE fiber mat has the potential as a promising antioxidant food packaging material.

scholarly journals Nonisothermal Cold Crystallization Kinetics of Poly(lactic acid)/Bacterial Poly(hydroxyoctanoate) (PHO)/Talc

2019 ◽  
Vol 17 (1) ◽  
pp. 1266-1278
Author(s):  
Omaima Alhaddad ◽  
Safaa H. El-Taweel ◽  
Yasser Elbahloul
Keyword(s):  
Thermal Stability ◽  
Lactic Acid ◽  
Crystallization Kinetics ◽  
Crystallization Rate ◽  
Cold Crystallization ◽  
Poly Lactic Acid ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Kinetics Of ◽  
Thermal Stability Of

AbstractThe effects of bacterial poly(hydroxyoctanoate) (PHO) and talc on the nonisothermal cold crystallization behaviours of poly(lactic acid) (PLA) were analysed with differential scanning calorimetry (DSC), and the thermal stability of the samples was observed with thermal gravimetric analysis (TGA). The modified Avrami’s model was used to describe the nonisothermal cold crystallization kinetics of neat PLA and its blends. The activation energies E for nonisothermal cold crystallization were calculated by the isoconversional method of Kissinger-Akahira-Sunose (KAS). The DSC results showed that the PLA/PHO blends were immiscible in the whole studied range, and as the PHO and talc content increased, the crystallization rate of PLA accelerated, and the crystallinity of PLA in the PLA samples increased. The values of the Avrami exponent indicated that the nonisothermal cold crystallization of the neat PLA and its blends exhibited heterogeneous, three-dimensional spherulitic growth. The E values were strongly dependent on PHO and talc. The TGA results showed that the presence of PHO and talc slightly influenced the thermal stability of PLA.

Comparison of physical and thermal properties of various wood-inorganic composites (WICs) derived by the sol-gel process

Holzforschung ◽  
2018 ◽  
Vol 72 (5) ◽  
pp. 379-386 ◽  
Author(s):  
Ke-Chang Hung ◽  
Jyh-Horng Wu
Keyword(s):  
Thermal Decomposition ◽  
Reaction Order ◽  
Sol Gel ◽  
Inorganic Composites ◽  
Conversion Rates ◽  
Sol Gel Process ◽  
Apparent Activation Energies ◽  
Kinetics Of ◽  
Thermal Stability Of ◽  
Better Than

AbstractThe physical properties and thermal decomposition kinetics of wood-inorganic composites (WICs) were in focus, which were prepared from methyltriethoxysilane (MTEOS), tetraethoxysilane (TEOS) and titanium (IV) isopropoxide (TTIP) by the sol-gel process. The hydrophobicity and dimensional stability of the composites were better than those of unmodified wood (Wcontr), but the performance of SiO2-based WICs (WICSiO2) was the best. The SEM-EDX micrographs show that silica is only distributed within the cell wall of the WICSiO2. By contrast, titania was deposited principally in the cell lumens of the WICTiO2. The thermal decomposition kinetic experiments show that the average apparent activation energies with conversion rates between 10% and 70% were 156–168 (Wcontr), 178–180 (WICMTEOS), 198–214 (WICTEOS) and 199–204 (WICTTIP) kJ mol−1at the impregnation level of 20% weight gain. The reaction order values calculated based on the Avrami theory were 0.51–0.57, 0.39–0.51, 0.36–0.47 and 0.28–0.51 in the same order of species indicated above. Accordingly, the dimensional and thermal stability of the wood could be enhanced effectively by the sol-gel process with silicon- and titanium-based alkoxides.

The Reaction Kinetics of Aluminum and Isopropanol

2012 ◽  
Vol 164 ◽  
pp. 21-25
Author(s):  
Xiu Hui Wang ◽  
Huan Huan Ni ◽  
Ye Cao ◽  
Gang Li ◽  
Hong Gao ◽  
...  
Keyword(s):  
Reaction Kinetics ◽  
Catalytic Mechanism ◽  
Reaction Order ◽  
Order Reaction ◽  
Zero Order ◽  
Zero Order Reaction ◽  
Kinetics Of

AlCl3was used as catalyst in the reaction. The reaction kinetics of aluminum and isopropanol was investigated in this paper. Metallograph showed that the surface of the aluminum bar had corrosive pitting. The reaction was zero order reaction when aluminum was overdosed. Reaction order was 0.75 when isopropanol was overdosed. Finally, catalytic mechanism of AlCl3was investigated and the reaction of corrosive pitting was the same as that in microbattery.

The Ordered Phase Formation in Ti-Al-Ga Alloys

1970 ◽  
Vol 28 ◽  
pp. 440-441
Author(s):  
Shiro Fujishiro ◽  
Harold L. Gegel
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Titanium Alloys ◽  
Growth Kinetics ◽  
Stoichiometric Composition ◽  
Good Potential ◽  
Alpha Titanium ◽  
Cold Rolled ◽  
Kinetics Of ◽  
Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

The effect of electrondonors on the polymerization kinetics of isoprene

1980 ◽  
Vol 45 (12) ◽  
pp. 3338-3346
Author(s):  
Miroslav Kašpar ◽  
Jiří Trekoval
Keyword(s):  
Induction Period ◽  
Ethyl Ether ◽  
Reaction Order ◽  
Propagation Rate ◽  
Reaction Scheme ◽  
Polymerization Kinetics ◽  
Polymerization Rate ◽  
Constant Concentration ◽  
Initial Concentration ◽  
Kinetics Of

The effect of small additions of 1-octene, butyl ethyl ether and triethylamine on the polymerization kinetics of isoprene (2-methyl-1,3-butadiene) in benzene initiated with butyllithium was investigated by employing the GLC analysis. The addition of 1-octane was reflected only in a shorter induction period of the reaction; the effect on the propagation rate was insignificant. With the increasing amount of butyl ethyl ether, the polymerization rate increases linearly, while the reaction order with respect to the concentration of triethylamine is variable and increases from 0.33 to 0.66 with the increasing concentration of the initiator. For a constant concentration of triethylamine, the reaction order with respect to the initial concentration of the initiator was found to vary considerably, reaching even negative values. A reaction scheme was suggested, taking into account the competition between two different solvates of alkyllithium.

In-situ stabilization of silver nanoparticles in polymer hydrogels for enhanced catalytic reduction of macro and micro pollutants

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Luqman Ali Shah ◽  
Rida Javed ◽  
Mohammad Siddiq ◽  
Iram BiBi ◽  
Ishrat Jamil ◽  
...  
Keyword(s):  
Catalytic Reduction ◽  
Thermo Gravimetric Analysis ◽  
Activation Parameters ◽  
Reduction Reaction ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
In Situ Stabilization ◽  
Hybrid Hydrogels ◽  
Kinetics Of

AbstractThe in-situ stabilization of Ag nanoparticles is carried out by the use of reducing agent and synthesized three different types of hydrogen (anionic, cationic, and neutral) template. The morphology, constitution and thermal stability of the synthesized pure and Ag-entrapped hybrid hydrogels were efficiently confirmed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and thermo gravimetric analysis (TGA). The prepared hybrid hydrogels were used in the decolorization of methylene blue (MB) and azo dyes congo red (CR), methyl Orange (MO), and reduction of 4-nitrophenol (4-NP) and nitrobenzene (NB) by an electron donor NaBH4. The kinetics of the reduction reaction was also assessed to determine the activation parameters. The hybrid hydrogen catalysts were recovered by filtration and used continuously up to six times with 98% conversion of pollutants without substantial loss in catalytic activity. It was observed that these types of hydrogel systems can be used for the conversion of pollutants from waste water into useful products.

scholarly journals Isothermal Vulcanization and Non-Isothermal Degradation Kinetics of XNBR/Epoxy/XNBR-g-Halloysite Nanotubes (HNT) Nanocomposites

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2872
Author(s):  
Seyed Mohamad Reza Paran ◽  
Ghasem Naderi ◽  
Elnaz Movahedifar ◽  
Maryam Jouyandeh ◽  
Krzysztof Formela ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Degradation Kinetics ◽  
Halloysite Nanotubes ◽  
Butadiene Rubber ◽  
Order Model ◽  
Scanning Calorimetry ◽  
Theoretical Methods ◽  
Vulcanization Kinetics ◽  
Kinetics Of ◽  
Thermal Stability Of

The effect of several concentrations of carboxylated nitrile butadiene rubber (XNBR) functionalized halloysite nanotubes (XHNTs) on the vulcanization and degradation kinetics of XNBR/epoxy compounds were evaluated using experimental and theoretical methods. The isothermal vulcanization kinetics were studied at various temperatures by rheometry and differential scanning calorimetry (DSC). The results obtained indicated that the nth order model could not accurately predict the curing performance. However, the autocatalytic approach can be used to estimate the vulcanization reaction mechanism of XNBR/epoxy/XHNTs nanocomposites. The kinetic parameters related to the degradation of XNBR/epoxy/XHNTs nanocomposites were also assessed using thermogravimetric analysis (TGA). TGA measurements suggested that the grafted nanotubes strongly enhanced the thermal stability of the nanocomposite.

Thermal Breakdown Kinetics of 1-Ethyl-3-Methylimidazolium Ethylsulfate Measured Using Quantitative Infrared Spectroscopy

2017 ◽  
Vol 71 (12) ◽  
pp. 2626-2631 ◽  
Author(s):  
Jeffrey L. Wheeler ◽  
McKinley Pugh ◽  
S. Jake Atkins ◽  
Jason M. Porter
Keyword(s):  
Thermal Stability ◽  
Room Temperature ◽  
Computational Models ◽  
Elevated Temperatures ◽  
Molar Absorptivity ◽  
Ir Absorption ◽  
Optical Cell ◽  
Multiple Samples ◽  
Kinetics Of ◽  
Thermal Stability Of

In this work, the thermal stability of the room temperature ionic liquid (RTIL) 1-ethyl-3-methylimidazolium ethylsulfate ([EMIM][EtSO4]) is investigated using infrared (IR) spectroscopy. Quantitative IR absorption spectral data are measured for heated [EMIM][EtSO4]. Spectra have been collected between 25 ℃ and 100 ℃ using a heated optical cell. Multiple samples and cell pathlengths are used to determine quantitative values for the molar absorptivity of [EMIM][EtSO4]. These results are compared to previous computational models of the ion pair. These quantitative spectra are used to measure the rate of thermal decomposition of [EMIM][EtSO4] at elevated temperatures. The spectroscopic measurements of the rate of decomposition show that thermogravimetric methods overestimate the thermal stability of [EMIM][EtSO4].

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