Thermal degradation kinetics of sepiolite

Clay Minerals ◽  
2020 ◽  
Vol 55 (1) ◽  
pp. 96-100 ◽  
Author(s):  
Yüksel Sarıkaya ◽  
Müşerref Önal ◽  
Abdullah Devrim Pekdemir
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Thermal Degradation ◽  
Degradation Kinetics ◽  
Analysis Data ◽  
Thermal Degradation Kinetics ◽  
Temperature Dependent ◽  
Thermal Change ◽  
Increasing Temperature ◽  
Kinetics Of

AbstractThe kinetic parameters of the thermal degradation of sepiolite were evaluated with a new method based on thermal analysis data. Thermogravimetric/differential thermal analysis curves were recorded for the natural and preheated sepiolite samples in the temperature range 25–800°C for 4 h. The temperature-dependent height of the exothermic heat flow peak for the thermal decomposition of sepiolite located at ~850°C on the differential thermal analysis curve was taken as a kinetic variable for the thermal degradation. A thermal change coefficient was defined depending on this variable because this coefficient fit to the Arrhenius equation was assumed as a rate constant for the thermal degradation. The Arrhenius plot showed that the degradation occurs in three steps. Two of these are due to stepwise dehydration and the third originated from dehydroxylation of sepiolite. Three activation energies were obtained that increase with the increasing temperature interval of the steps.

scholarly journals Thermal Degradation Kinetics and Modeling Study of Ultra High Molecular Weight Polyethylene (UHMWP)/Graphene Nanocomposite

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1597
Author(s):  
Iman Jafari ◽  
Mohamadreza Shakiba ◽  
Fatemeh Khosravi ◽  
Seeram Ramakrishna ◽  
Ehsan Abasi ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Thermal Degradation ◽  
High Molecular Weight ◽  
Degradation Kinetics ◽  
Graphene Nanosheets ◽  
Thermal Degradation Kinetics ◽  
Graphene Nanocomposites ◽  
Kinetics Of ◽  
Ultra High Molecular Weight

The incorporation of nanofillers such as graphene into polymers has shown significant improvements in mechanical characteristics, thermal stability, and conductivity of resulting polymeric nanocomposites. To this aim, the influence of incorporation of graphene nanosheets into ultra-high molecular weight polyethylene (UHMWPE) on the thermal behavior and degradation kinetics of UHMWPE/graphene nanocomposites was investigated. Scanning electron microscopy (SEM) analysis revealed that graphene nanosheets were uniformly spread throughout the UHMWPE’s molecular chains. X-Ray Diffraction (XRD) data posited that the morphology of dispersed graphene sheets in UHMWPE was exfoliated. Non-isothermal differential scanning calorimetry (DSC) studies identified a more pronounced increase in melting temperatures and latent heat of fusions in nanocomposites compared to UHMWPE at lower concentrations of graphene. Thermogravimetric analysis (TGA) and derivative thermogravimetric (DTG) revealed that UHMWPE’s thermal stability has been improved via incorporating graphene nanosheets. Further, degradation kinetics of neat polymer and nanocomposites have been modeled using equations such as Friedman, Ozawa–Flynn–Wall (OFW), Kissinger, and Augis and Bennett’s. The "Model-Fitting Method” showed that the auto-catalytic nth-order mechanism provided a highly consistent and appropriate fit to describe the degradation mechanism of UHMWPE and its graphene nanocomposites. In addition, the calculated activation energy (Ea) of thermal degradation was enhanced by an increase in graphene concentration up to 2.1 wt.%, followed by a decrease in higher graphene content.

scholarly journals Thermal Degradation Kinetics of Sugarcane Bagasse and Soft Wood Cellulose

Materials ◽  
2017 ◽  
Vol 10 (11) ◽  
pp. 1246 ◽  
Author(s):  
Samson M. Mohomane ◽  
Tshwafo E. Motaung ◽  
Neerish Revaprasadu
Keyword(s):  
Thermal Degradation ◽  
Sugarcane Bagasse ◽  
Degradation Kinetics ◽  
Thermal Degradation Kinetics ◽  
Wood Cellulose ◽  
Kinetics Of

scholarly journals Thermal degradation kinetics of para-substituted poly (styrene peroxide)s in solution

2002 ◽  
Vol 86 (4) ◽  
pp. 957-961 ◽  
Author(s):  
Priyadarsi De ◽  
Sujay Chattopadhyay ◽  
Giridhar Madras ◽  
D. N. Sathyanarayana
Keyword(s):  
Thermal Degradation ◽  
Degradation Kinetics ◽  
Thermal Degradation Kinetics ◽  
Kinetics Of

Thermal Degradation Kinetics of Epoxy Resins and Their Drilling Application

2018 ◽  
Author(s):  
Abdullah Al-Yami ◽  
Vikrant Wagle ◽  
Walmy Cuello Jimenez ◽  
Paul Jones
Keyword(s):  
Thermal Degradation ◽  
Epoxy Resins ◽  
Degradation Kinetics ◽  
Thermal Degradation Kinetics ◽  
Kinetics Of

Thermo-oxidative and thermal degradation kinetics of silica/polymethyl methacrylate composites with electrostatic interaction phase interfaces

2019 ◽  
Vol 39 (2) ◽  
pp. 105-116 ◽  
Author(s):  
Hongyan Li ◽  
Yongqiang Fu ◽  
Hongli Liu ◽  
Cong Sun ◽  
Ruyi Li ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Thermal Degradation ◽  
Polymethyl Methacrylate ◽  
Electrostatic Interaction ◽  
Degradation Kinetics ◽  
Thermal Degradation Kinetics ◽  
Degradation Kinetic ◽  
Further Development ◽  
Kinetics Of ◽  
Insulation Performance

AbstractThe thermo-oxidative and thermal degradation kinetic parameters of polymethyl methacrylate-methacryloxyethyltrimethyl ammonium chloride/silica aerogel composites (PMMA-MTC/SA) were investigated in this paper and were compared with the thermal stability and thermal conductivity of different types of composites. As a composite with electrostatic interaction, the thermo-oxidative and thermal degradation activation energies (E) of PMMA-MTC/SA were 173.97 and 188.05 kJ/mol, respectively. The results indicated that the electrostatic interaction could indeed enhance the thermal stability of silica/polymethyl methacrylate composites on the premise of good mechanical properties and heat insulation performance. It is of great significance for the further development of silica-based thermal insulation composites.

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