Thermal stability of phosphorus-containing epoxy resins by thermogravimetric analysis

The thermal stabilities of epoxy resin/diethyl bis(2-hydroxyethyl)aminomethylphosphonate (EP/DBAMP) systems were investigated by thermogravimetric analysis (TGA) under non-isothermal conditions in nitrogen atmosphere. Kissinger and Flynn–Wall–Ozawa methods were used to study the thermal degradation process. The results showed a remarkable increase of activation energy ( E) in the presence of DBAMP, which indicated that the addition of DBAMP retarded the thermal degradation of EP. The Flynn–Wall–Ozawa analysis further revealed that DBAMP significantly increased the activation energy in the early stage of EP’s thermal degradation, demonstrating that DBAMP had improved the initial thermal stability and modified the flame retardancy of EP in the thermal degradation process.

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Non-isothermal degradation kinetics for polycarbonate/ polymethylphenylsilsesquioxane composites

e-Polymers ◽

10.1515/epoly.2010.10.1.1 ◽

2010 ◽

Vol 10 (1) ◽

Cited By ~ 9

Author(s):

Jiangbo Wang ◽

Zhong Xin

Keyword(s):

Activation Energy ◽

Thermogravimetric Analysis ◽

Thermal Degradation ◽

Flame Retardancy ◽

Degradation Kinetics ◽

Degradation Process ◽

Nitrogen Atmosphere ◽

Ozawa Method ◽

Degradation Behaviors ◽

Thermal Degradation Process

AbstractThe thermal degradation behaviors of PC/PMPSQ (polymethylphenylsilsesquioxane) systems were investigated by thermogravimetric analysis (TGA) under non-isothermal conditions in nitrogen atmosphere. During non-isothermal degradation, Kissinger and Flynn-Wall-Ozawa methods were used to analyze the thermal degradation process. The results showed that a remarkable decrease in activation energy ( E ) was observed in the early and middle stages of thermal degradation in the presence of PMPSQ, which indicated that the addition of PMPSQ promoted the thermal degradation of PC. Flynn-Wall-Ozawa method further revealed that PMPSQ significantly increased the activation energy of PC thermal degradation in the final stage, which illustrated that the PMPSQ stabilized the char residues and improved the flame retardancy of PC in the final period of thermal degradation process

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Thermal degradation kinetics of oxo-degradable PP/PLA blends

Journal of Polymer Engineering ◽

10.1515/polyeng-2018-0073 ◽

2018 ◽

Vol 39 (1) ◽

pp. 58-67 ◽

Cited By ~ 4

Author(s):

Dev K. Mandal ◽

Haripada Bhunia ◽

Pramod K. Bajpai

Keyword(s):

Activation Energy ◽

Thermal Stability ◽

Thermogravimetric Analysis ◽

Thermal Degradation ◽

Kinetic Parameters ◽

Degradation Kinetics ◽

Nitrogen Atmosphere ◽

Thermal Degradation Kinetics ◽

Heating Rates ◽

Kinetics Of

AbstractIn this article, the influence of polylactide and pro-oxidant on the thermal stability, degradation kinetics, and lifetime of polypropylene has been investigated using thermogravimetric analysis under nitrogen atmosphere at four different heating rates (i.e. 5, 10, 15, and 20°C/min). The kinetic parameters of degradation were studied over a temperature range of 30–550°C. The derivative thermogravimetric curves have indicated single stage and two stage degradation processes. The activation energy was evaluated by using the Kissinger, Kim-Park, and Flynn-Wall methods under the nitrogen atmosphere. The activation energy value of polypropylene was much higher than that of polylactide. Addition of polylactide and pro-oxidant in polypropylene decreased the activation energy. The lifetime of polypropylene has also decreased with the addition of polylactide and pro-oxidant.

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Thermal Stability and Kinetic Analysis of Xanthoceras sorbifolia Polysaccharide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.3904 ◽

2012 ◽

Vol 518-523 ◽

pp. 3904-3907 ◽

Cited By ~ 1

Author(s):

Quan Cheng Zhou ◽

Hong Mei Zhang ◽

De Mao Li

Keyword(s):

Activation Energy ◽

Thermal Stability ◽

Kinetic Model ◽

Thermal Degradation ◽

Kinetic Analysis ◽

Large Scale ◽

Degradation Process ◽

Second Step ◽

Step Process ◽

Thermal Degradation Process

Pyrolysis and kinetic analysis of Xanthoceras Sorbifolia polysaccharide were evaluated using the TG-DTG/DTA method. The results indicated that its mass loss occured in three-step process . The first step could be attributed to the expulsion of water of crystallization at 25 - 176 °C. The second step corresponded to the large scale degradation of X. Sorbifolia polysaccharide in the temperature range of 179 - 661 °C. The final step was slow degradation of residues. Heating rate had significant effects on the pyrolysis of X. Sorbifolia polysaccharide and nitrogen could improve its stability. A close value of activation energy E of the thermal degradation process has been obtained by FWO, KAS and Popescu methods. The possible kinetic model was estimated to be Jander 5 (g(α)=[1-(1-α)1/3]1/2.

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Devolatilization of African Palm (Elaeis guineensis) Husk studied by TG-MS

Ingeniería e Investigación ◽

10.15446/ing.investig.v38n2.67743 ◽

2018 ◽

Vol 38 (2) ◽

pp. 9-17

Author(s):

Alberto Ricardo Albis Arrieta ◽

Ever Ortiz Muñoz ◽

Ismael Piñeres Ariza ◽

Andrés Felipe Suárez Escobar ◽

Marley Cecilia Vanegas Chamorro

Keyword(s):

Activation Energy ◽

Thermal Degradation ◽

Mass Spectroscopy ◽

Elaeis Guineensis ◽

Degradation Process ◽

Pyrolysis Process ◽

Distributed Activation Energy Model ◽

Evolved Gas ◽

Secondary Reactions ◽

Thermal Degradation Process

Using simultaneous thermogravimetrical analysis coupled with mass spectroscopy, the pyrolysis of African palm husk, using several heat rates and programs was performed. Seven relations of mass/charge were followed of the evolved gas of the pyrolysis process, fitting the kinetics and the mass spectroscopy signals to the distributed activation energy model (DAEM) with different numbers of pseudo-components. Fitting with four pseudo-components proved to be the best for modeling the thermal degradation process. Kinetic parameters were not affected by the heating rate or program employed, which agrees with other reports for similar biomass. Methane, methanol formaldehyde, furfural were successfully fitted to the DAEM model, nevertheless CO2 and NO2 were not able to be represented by this model due to its production in secondary reactions in gaseous phase.

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Thermal Behavior of Polychlal Fiber Modified with Phosphorus Oxychloride

Journal of Fire Sciences ◽

10.1177/073490419201000404 ◽

1992 ◽

Vol 10 (4) ◽

pp. 323-334 ◽

Cited By ~ 1

Author(s):

Kazuhiko Fukatsu

Keyword(s):

Activation Energy ◽

Weight Loss ◽

Thermogravimetric Analysis ◽

Thermal Behavior ◽

Phosphorus Oxychloride ◽

Degradation Kinetics ◽

Degradation Process ◽

Rapid Weight Loss ◽

Maximum Activation ◽

Thermal Degradation Process

The thermal behavior of polychlal fiber partially phosphorylated with phosphorus oxychloride has been studied using a conventional dynamic thermogravimetric technique. The dynamic thermogravimetric analysis curves have been analyzed using analytical methods reported in the literature to obtain information about the sequential stages in the thermal degradation process. The data obtained reveals that the phosphorus system is capable of modifying the degradation kinetics, with the phosphorylated polychlal fiber having a reduced maximum activation energy and more rapid weight loss dur ing the initial degradation.

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Kinetic Study of PVC Pyrolysis in Air by Thermogravimetric Analysis Using the Friedman Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.427.64 ◽

2012 ◽

Vol 427 ◽

pp. 64-69 ◽

Cited By ~ 1

Author(s):

Bin Han ◽

Yu Long Wu ◽

Wei Feng ◽

Zhen Chen ◽

Ming De Yang

Keyword(s):

Activation Energy ◽

Thermogravimetric Analysis ◽

Thermal Degradation ◽

Heating Rate ◽

Inert Atmosphere ◽

Nitrogen Atmosphere ◽

Pyrolysis Process ◽

Pyrolysis Mechanism ◽

Second Stage ◽

Friedman Method

The thermal degradation of PVC in air ambience was investigated by the thermogravimetric analysis (TGA). The experiments were carried out at different heating rate of 5, 10, 20 and 40°C/min, respectively. The activation energy was calculated by the Friedman method. The pyrolysis mechanism of PVC in air was discussed and compared with that in Nitrogen atmosphere. The pyrolysis process of PVC in air could be divided into two main stages: 200 °C ~ 380 °C and 400 °C ~ 600 °C, which obtained by TGA at the heating rate of 5°C/min. The second stage could be further subdivided into two parts by 465 °C. It can be concluded that the oxygen in air affected the second stage more obviously than that of the first one, in comparison with inert atmosphere. The activation energy of the second stage was still larger than the first stage.

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Kinetic study of the stabilizing effect of aluminum trihydroxide on thermal degradation of epoxy resin

e-Polymers ◽

10.1515/epoly-2013-0091 ◽

2014 ◽

Vol 14 (2) ◽

pp. 133-137 ◽

Cited By ~ 2

Author(s):

Jiangbo Wang ◽

Jialin Fang ◽

Chengwei Wang ◽

Yongyou Li ◽

Mengjiao Huang

Keyword(s):

Activation Energy ◽

Thermal Degradation ◽

Epoxy Resin ◽

Fire Retardant ◽

Degradation Process ◽

Ozawa Method ◽

Degradation Behaviour ◽

Stabilizing Effect ◽

Thermal Degradation Process ◽

Aluminum Trihydroxide

AbstractThe stabilizing effect of epoxy resin (EP)/aluminum trihydroxide (ATH) was measured by thermogravimetric analysis (TGA) in an N2 flow. The Kissinger and Flynn-Wall-Ozawa methods were used to determine the activation energy of non-isothermal degradation at different stages. The results showed that there was a slight increase in activation energy after ATH was added. It confirms the fire-retardant effect of ATH on the thermal degradation behaviour of pure EP. The Flynn-Wall-Ozawa method showed that flame-retardant ATH remarkably enhanced the activation energy of the thermal degradation process for EP, albeit the conversion rate being only 10%, which demonstrated the stabilization of ATH to the char layer of EP.

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Thermal behavior of some aromatic copolyethers containing a propylenic spacer

Open Chemistry ◽

10.2478/bf02476237 ◽

2005 ◽

Vol 3 (1) ◽

pp. 53-62 ◽

Cited By ~ 2

Author(s):

Nicolae Hurduc ◽

Cristina Damian ◽

Anca Tarus ◽

Violeta Toader ◽

Natalia Hurduc

Keyword(s):

Thermal Stability ◽

Thermal Degradation ◽

Liquid Crystalline ◽

Degradation Mechanism ◽

Degradation Process ◽

Stability Study ◽

Maximum Temperature ◽

Weakest Link ◽

Starting Point ◽

Thermal Degradation Process

AbstractThe main objective of this paper is to study the thermal stability of some aromatic copolyethers containing a propylenic spacer. Some of the investigated copolyethers displayed a liquid crystalline (LC) behavior, with the presence of the mesogenic groups in the main chain, inducing high values of the thermal transition temperatures. As a consequence, a thermal stability study was necessary to establish the maximum temperature value for the LC behavior characterization. A thermal degradation mechanism is proposed, taking into consideration the azobenzenic unit as the weakest link in the polymer chain and thus, the starting point of the thermal degradation process. The degradation mechanisms were correlated with the chemical structure and the polarity and conformation of the chains. Conformational analysis was performed using molecular simulations. Freeman-Caroll and Coats-Redfern methods were used to calculate some kinetic characteristics.

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Thermal Degradation Characteristics and Kinetics of Oxy Combustion of Corn Residues

Advances in Materials Science and Engineering ◽

10.1155/2015/304395 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 14

Author(s):

Poramate Sittisun ◽

Nakorn Tippayawong ◽

Darunee Wattanasiriwech

Keyword(s):

Activation Energy ◽

Thermal Degradation ◽

Degradation Process ◽

Similar Magnitude ◽

Heating Rates ◽

Decomposition Rates ◽

Similar Weight ◽

Thermal Degradation Process ◽

Kinetics Of ◽

Corn Residues

Thermogravimetric analysis was used to investigate oxy combustion of corncob and stover. The biomass samples were heated from ambient temperature to 900°C at different heating rates of 10, 30, and 50 K/min. Both biomass samples showed similar weight loss patterns with three zones, corresponding to dehydration, devolatilization, and char combustion, but displayed different degradation temperatures. Increasing heating rate was found to shift the degradation patterns to higher temperatures. Decomposition rates of cob and stover may have been influenced by their lignocellulosic composition. The kinetic parameters of the thermal degradation process were also determined and compared using the Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose methods. Both methods were found to give similar values and patterns of activation energy against conversion fraction. The average values were found to be in similar magnitude to those reported in the literature, around 170 and 148 kJ/mol for cob and stover, respectively.

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