Kinetic analysis and reaction mechanism of p-alkoxybenzyl alcohol ([4-(hydroxymethyl)phenoxymethyl]polystyrene) resin pyrolysis: Revealing new information on thermal stability

A kinetic analysis of the reaction between peracetic acid (AcOOH), and tetrakis (pentafluorophenyl) - 21H, 23H-porphine iron(III) chloride Fe(F20TPP)Cl, in acetonitrile showed that the peracetic acid oxidatively destroys Fe(F20TPP)Cl. This is in contrast to an assumption that the oxidative degradation of metalloporphyrins can be prevented by the introduction of electron-withdrawing substituents into the phenyl groups of the porphyrin ligand. A UV-visible spectroscopic study showed a degree of macro cycle destruction of the tetrapyrrole conjucation of the metalloporphyrin. The degradation takes place via oxoperferryl species. The first step of the reaction mechanism is the reversible formation of an adduct ?X? (k1/k-1) between Fe(F20TPP)Cl and peracetic acid, followed by an irreversible step (k2) for the formation of oxoperferryl species.

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Kinetic analysis of thermal stability of human low‐density lipoproteins: A model for LDL fusion in atherogenesis

The FASEB Journal ◽

10.1096/fasebj.27.1_supplement.1208.8 ◽

2013 ◽

Vol 27 (S1) ◽

Author(s):

Mengxiao Lu ◽

Shobini Jayaraman ◽

Donald L Gantz ◽

Haya Herscovitz ◽

Olga Gursky

Keyword(s):

Thermal Stability ◽

Kinetic Analysis ◽

Low Density Lipoproteins ◽

Low Density ◽

Thermal Stability Of

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Nonisothermal Kinetic Analysis and AC Conductivity for Polyvinyl Chloride (PVC)/Zinc Oxide (ZnO) Nanocomposite

Advances in Polymer Technology ◽

10.1155/2020/1254301 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Huda AlFannakh

Keyword(s):

Thermal Stability ◽

Zinc Oxide ◽

Kinetic Analysis ◽

Zno Nanoparticles ◽

Ac Conductivity ◽

Zno Nanoparticle ◽

Nonisothermal Kinetic ◽

Increasing Temperature ◽

Host Polymer ◽

Nonisothermal Kinetic Analysis

The behavior of polyvinyl chlorine (PVC)/zinc oxide (ZnO) nanoparticles was investigated. To improve the dispersion and distribution of zinc nanoparticles within the host polymer (PVC), they were treated with water before being added to the polymer. The nanocomposite samples were prepared by casting method using different weight ratios of ZnO nanoparticles. The prepared nanocomposite samples were characterized by thermogravimetric analysis (TGA). Both thermal stability and kinetic analysis of the prepared samples were investigated. The ZnO nanoparticles lower the activation energy and decrease the thermal stability of PVC. Kissinger, Flynn-Wall-Ozawa, and Kissinger-Akahira-Sunose models were used in the nonisothermal kinetic analysis of PVC/ZnO nanocomposite samples. The thermal stability behavior due to the addition of zinc oxide nanoparticles was explained and correlated with the behavior of the kinetic parameters of the samples. The AC conductivity as function of frequency and temperature was also investigated. The addition of ZnO nanoparticle increases the AC conductivity, and the temperature-independent region decreased by increasing temperature. Both S and A coefficients were predicted using the Jonscher power law and OriginLab software. The trends of S and A coefficients were discussed based on the glass transition of the host polymer.

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