Kinetics of the Exothermic Decomposition Reaction of N-Methyl-N-nitro-2,2,2-trinitroethanamine

The thermal analyses, thermogravimetry (TG), and differential thermal analysis (DTA) of PbOHCl, PbOHBr, and PbOHI reveal that the initial mode of decomposition is via dehydroxylation. Calorimetric measurements along with related enthalpy values for the decomposition reaction are given.The infrared spectra of these compounds are interpreted in terms of folded bands of (PbOH+)n tied together by halide ions consistent with their crystal structures.The kinetics of thermal decomposition of lead hydroxyhalides follow a diffusion-type rate equation which is in contrast to the simple first-order rate equation observed for most Cd, Zn, and Cu compounds. These two distinct rates are interpreted in terms of mobile OH or H species in the dehydroxylation step.

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Alloying Effects on Reverse Transformation to Austenite from Pearlite or Tempered Martensite Structures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.3400 ◽

2010 ◽

Vol 638-642 ◽

pp. 3400-3405 ◽

Cited By ~ 2

Author(s):

Goro Miyamoto ◽

Zhao Dong Li ◽

Hirokazu Usuki ◽

Tadashi Furuhara

Keyword(s):

Decomposition Reaction ◽

Reverse Transformation ◽

Transformation Kinetics ◽

Tempered Martensite ◽

Austenite Grain Size ◽

Austenite Grain ◽

Cr Addition ◽

Alloying Effects ◽

Kinetics Of ◽

Martensite Structure

Reverse transformation has been frequently used to refine austenite grain size for refining ferrite, pearlite and martensite structures. However, kinetics and microstructure change during reverse transformation to austenite has not been examined systematically compared with the austenite decomposition reaction. Therefore, alloying effects of 1mass% Mn, Si and Cr on reverse transformation kinetics from pearlite and tempered martensite structures in Fe-0.6mass%C alloys were investigated in this study. Vickers hardness of all the specimens increases with increasing holding time at 1073K because reversely-formed austenite transforms to martensite by quenching. In the reverse transformation from pearlite structure, the kinetics of reverse transformation is hardly changed by the Mn addition while Si and Cr additions delay it. Kinetics of reverse transformation from tempered martensite structure becomes slower than from the pearlite structure in all the alloys. In particular, retarding effect by the Cr addition is most significant among those elements.

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Thermal Decomposition Kinetics of Flame Retardant Polybutylene Terephthalate Matrix Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.956.181 ◽

2019 ◽

Vol 956 ◽

pp. 181-191

Author(s):

Jian Lin Xu ◽

Bing Xue Ma ◽

Cheng Hu Kang ◽

Cheng Cheng Xu ◽

Zhou Chen ◽

...

Keyword(s):

Activation Energy ◽

Thermal Decomposition ◽

Flame Retardant ◽

Mass Loss Rate ◽

Decomposition Reaction ◽

Decomposition Kinetics ◽

Thermal Decomposition Kinetics ◽

Heating Rates ◽

Polybutylene Terephthalate ◽

Kinetics Of

The thermal decomposition kinetics of polybutylene terephthalate (PBT) and flame-retardant PBT (FR-PBT) were investigated by thermogravimetric analysis at various heating rates. The kinetic parameters were determined by using Kissinger, Flynn-Wall-Ozawa and Friedman methods. The y (α) and z (α) master plots were used to identify the thermal decomposition model. The results show that the rate of residual carbon of FR-PBT is higher than that of PBT and the maximum mass loss rate of FR-PBT is lower than that of PBT. The values of activation energy of PBT (208.71 kJ/mol) and FR-PBT (244.78 kJ/mol) calculated by Kissinger method were higher than those of PBT (PBT: 195.54 kJ/mol) and FR-PBT (FR-PBT: 196.00 kJ/mol) calculated by Flynn-Wall-Ozawa method and those of PBT and FR-PBT (PBT: 199.10 kJ/mol, FR-PBT: 206.03 kJ/mol) calculated by Friedman methods. There is a common thing that the values of activation energy of FR-PBT are higher than that of PBT in different methods. The thermal decomposition reaction models of the PBT and FR-PBT can be described by Avarami-Erofeyev model (A1).

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Analysis of oxidation decomposition reaction scheme and its kinetics of delafossite-type oxide CuLaO2 by thermogravimetry and high-temperature X-ray diffraction

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-015-4723-9 ◽

2015 ◽

Vol 123 (3) ◽

pp. 1833-1839 ◽

Cited By ~ 2

Author(s):

Fumito Fujishiro ◽

Sayo Takaichi ◽

Kosuke Hirakawa ◽

Takuya Hashimoto

Keyword(s):

High Temperature ◽

Decomposition Reaction ◽

Reaction Scheme ◽

X Ray Diffraction ◽

X Ray ◽

Kinetics Of

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Thermal behavior and non-isothermal decomposition reaction kinetics of catalyzed hniw-cmdb propellant

Journal of Physics Conference Series ◽

10.1088/1742-6596/1507/2/022011 ◽

2020 ◽

Vol 1507 ◽

pp. 022011

Author(s):

S Y Xu ◽

F Q Zhao ◽

E G Yao ◽

H Y Jiang ◽

J H Yi ◽

...

Keyword(s):

Thermal Behavior ◽

Reaction Kinetics ◽

Decomposition Reaction ◽

Isothermal Decomposition ◽

Kinetics Of

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Kinetics of Peroxide Vulcanization of Natural Rubber

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/147776061202800405 ◽

2012 ◽

Vol 28 (4) ◽

pp. 201-220 ◽

Cited By ~ 6

Author(s):

Rejitha Rajan ◽

Siby Varghese ◽

K.E. George

Keyword(s):

Mechanical Properties ◽

Natural Rubber ◽

Crosslinking Agent ◽

Decomposition Reaction ◽

Dominant Factor ◽

Compression Set ◽

Cure Time ◽

Minimum Residual ◽

Vulcanization Kinetics ◽

Kinetics Of

This study was undertaken to optimize the vulcanization conditions and explore the effect of residual peroxide in the peroxide vulcanization of natural rubber. The study was followed through the kinetics of the vulcanization reaction at various temperatures viz. 150,155,160 and 165°C. Dicumyl peroxide (DCP) was used as the crosslinking agent. The Monsanto Rheometer was used to investigate the different crosslinking stages and vulcanization kinetics. The thermal decomposition of peroxide followed a first order free radical decomposition reaction. Half-lives at various temperatures were determined. The percentage of residual peroxide was calculated from the cure kinetic data. The effect of residual peroxide on mechanical properties was studied at various peroxide levels and also by extending the cure time (from t90 to t95 and then to t100). Mechanical properties such as tensile strength, elongation at break, modulus and compression set (70 and 100°C) were measured. Excess peroxide was found to cause a high compression set at elevated temperature and the cure time was selected to achieve minimum residual peroxide in the product. Results indicate that peroxide concentration is the dominant factor controlling the crosslink density and hence the properties of the vulcanizates.

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