Thermal Stability and Kinetic Analysis of Xanthoceras sorbifolia Polysaccharide

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.

Download Full-text

Thermal stability of phosphorus-containing epoxy resins by thermogravimetric analysis

Polymers and Polymer Composites ◽

10.1177/0967391118808701 ◽

2018 ◽

Vol 26 (7) ◽

pp. 400-407 ◽

Cited By ~ 1

Author(s):

Xiaomin Lv ◽

Jialin Fang ◽

Jinghan Xie ◽

Xue Yang ◽

Jiangbo Wang

Keyword(s):

Activation Energy ◽

Thermal Stability ◽

Thermogravimetric Analysis ◽

Thermal Degradation ◽

Early Stage ◽

Degradation Process ◽

Nitrogen Atmosphere ◽

Thermal Stabilities ◽

Phosphorus Containing ◽

Thermal Degradation Process

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.

Download Full-text

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

Download Full-text

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.

Download Full-text

Thermal and kinetic analysis of pure and contaminated ionic liquid: 1-butyl-2.3-dimethylimidazolium chloride (BDMIMCl)

Polish Journal of Chemical Technology ◽

10.1515/pjct-2016-0038 ◽

2016 ◽

Vol 18 (2) ◽

pp. 122-125 ◽

Cited By ~ 2

Author(s):

Ayyaz Muhammad

Keyword(s):

Activation Energy ◽

Thermal Stability ◽

Thermal Decomposition ◽

Ionic Liquid ◽

Thermal Degradation ◽

Kinetic Analysis ◽

Kinetic Parameters ◽

Process Design ◽

Research Work ◽

Thermal Stability Of

Abstract In this research work, thermal decomposition and kinetic analysis of pure and contaminated imidazolium based ionic liquid (IL) has been investigated. As thermal decomposition and kinetics evaluation plays a pivotal role in effective process design. Therefore, thermal stability of pure 1-butyl-2,3-dimethylimidazolium chloride (BDMIMCl) was found to be higher than the sample of IL with the addition of 20% (wt.) NH4Cl as an impurity. The activation energy of thermal degradation of IL and other kinetic parameters were determined using Coats Redfern method. The activation energy for pure IL was reduced in the presence of NH4Cl as contaminant i.e., from 58.7 kJ/mol to 46.4 kJ/mol.

Download Full-text

Thermal degradation process of the cured phenolic triazine thermoset resin (Primaset® PT-30). Part I. Systematic non-isothermal kinetic analysis

Thermochimica Acta ◽

10.1016/j.tca.2011.03.014 ◽

2011 ◽

Vol 519 (1-2) ◽

pp. 114-124 ◽

Cited By ~ 9

Author(s):

Bojan Janković

Keyword(s):

Thermal Degradation ◽

Kinetic Analysis ◽

Degradation Process ◽

Thermoset Resin ◽

Thermal Degradation Process ◽

Isothermal Kinetic Analysis ◽

Isothermal Kinetic

Download Full-text

Kinetics of Thermal Degradation of Ionic Liquid Regenerated Cellulose

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.488-489.923 ◽

2012 ◽

Vol 488-489 ◽

pp. 923-927

Author(s):

Nawshad Muhammad ◽

Zakaria B. Man ◽

M. Azmi Bustam Khalil ◽

Sikander Rafiq

Keyword(s):

Activation Energy ◽

Ionic Liquid ◽

Kinetic Model ◽

Thermal Degradation ◽

Kinetic Parameters ◽

Dynamic Condition ◽

Degradation Process ◽

Waste Paper ◽

Regenerated Cellulose ◽

Kinetics Of

In the present work ionic liquid has been used for the regeneration of cellulose from waste writing paper. The regenerated cellulose was characterized by TGA, FTIR and XRD analyses. Kinetics of thermal degradation of this cellulose was carried out under dynamic condition using thermogravimetry. Coats-Redfern kinetic model was used to determine the kinetic parameters for the degradation process. The activation energy for the thermal degradation of the regenerated cellulose has been found to be less than the precursor waste paper.

Download Full-text

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.

Download Full-text

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.

Download Full-text

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.

Download Full-text