Activation energy and curing behavior of resol- and novolac-type phenolic resins by differential scanning calorimetry and thermogravimetric analysis

2003 ◽  
Vol 89 (10) ◽  
pp. 2589-2596 ◽  
Author(s):  
Young-Kyu Lee ◽  
Dae-Jun Kim ◽  
Hyun-Joong Kim ◽  
Teak-Sung Hwang ◽  
Miriam Rafailovich ◽  
...  
Keyword(s):  
Activation Energy ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Scanning Calorimetry ◽  
Phenolic Resins ◽  
Curing Behavior

scholarly journals Using the Coats-Redfern Method during Thermogravimetric Analysis and Differential Scanning Calorimetry Analysis of the Thermal Stability of Epoxy and Epoxy/Silica Nanoparticle Nanocomposites

2020 ◽  
Vol 55 (4) ◽  
Author(s):  
Subhi A. Al-Bayaty ◽  
Raheem A.H. Al-Uqaily ◽  
Najwa J. Jubier
Keyword(s):  
Activation Energy ◽  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Thermogravimetric Analysis ◽  
Heating Rate ◽  
Silica Nanoparticle ◽  
Frequency Factor ◽  
Inert Atmosphere ◽  
Diffusion Control ◽  
Scanning Calorimetry

In this paper, we provide a study of the thermal decomposition behavior of epoxy and epoxy/silica nanoparticle nanocomposites by using thermogravimetric analysis and differential scanning calorimetry techniques at temperatures ranging from 25°C to 600°C, using a constant heating rate of 10°C per minute under inert atmosphere. With increasing silica nanoparticle percentages of 2%, 4%, 6% and 8%, the kinetic parameters of the activation energy, frequency factor, and thermodynamics property were determined at conversion ranges between 20% to 80% using the Coats-Redfern method for diffusion control reaction (Janders) model. The Arrhenius equation for epoxy decomposition at a heating rate of 10°Cper minute equaled 5.7278x e185.984/RT. Thermal decomposition occurred through two stages: (1) with volatile removal and (2) with a random chain break. The effects of variation of silica nanoparticle percentages on glass transition temperature was investigated. The activation energy, frequency factor, rate constant, and other thermodynamic properties increased with additional silica nanoparticle content due to more bonding, as it needed more heat to break.

Thermal Stability of N-Heterocycle-Stabilized Iodanes – A Systematic Investigation

2019 ◽  
Author(s):  
Andreas Boelke ◽  
Yulia A. Vlasenko ◽  
Mekhman S. Yusubov ◽  
Boris Nachtsheim ◽  
Pavel Postnikov
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Systematic Investigation ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

<p>The thermal stability of pseudocyclic and cyclic <i>N</i>-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-l<sup>3</sup>-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. NHIs bearing <i>N</i>-heterocycles with a high N/C-ratio such as triazoles show among the lowest descomposition temperatures and the highest decomposition energies. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation. </p>

scholarly journals Conversion of palm oil to new sulfur-based polymer by inverse vulcanization

2021 ◽  
Vol 287 ◽  
pp. 02014
Author(s):  
Amin Abbasi ◽  
Mohamed Mahmoud Nasef ◽  
Wan Zaireen Nisa Yahya ◽  
Muhammad Moniruzzaman
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Fourier Transform ◽  
Thermogravimetric Analysis ◽  
Palm Oil ◽  
Elemental Sulfur ◽  
Molten State ◽  
Scanning Calorimetry ◽  
Environmental Friendly ◽  
Sulfur Containing

The conversion of palm oil into a sulfur-based polymer by copolymerization with sulfur powder at its molten state is herein reported. The obtained sulfur-containing polymer was characterized using Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) to demonstrate the successful conversion. The disappearance of the peaks related to vinylic groups of oil together with the appearance of a peak representing C-H rocking vibrations in the vicinity of C-S bonds confirmed the copolymerization of sulfur with oil. TGA revealed that the polymers have thermal stability up to 230°C under nitrogen and the polymers leave 10% sulfur-rich ash. DSC proved that a small amount of elemental sulfur remained unreacted in the polymer, which showed amorphous and heavily crosslinked structure resembling thermosets. These copolymers are an environmental-friendly polymeric material promoting the utilization of the abundant sulfur while also adding value to palm oil.

Synthesis, characterization, and structures of zircona- and boracyclosiloxanes with ferrocenyl substituents

2002 ◽  
Vol 80 (11) ◽  
pp. 1469-1480 ◽  
Author(s):  
Karena Thieme ◽  
Sara C Bourke ◽  
Juan Zheng ◽  
Mark J MacLachlan ◽  
Fojan Zamanian ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
The Novel ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Multinuclear Nmr Spectroscopy

The novel zirconatetraferrocenylcyclotrisiloxane Cp2Zr(OSiFc2)2O (6), dizirconatetraferrocenylcyclotetrasiloxane [Cp2Zr(OSiFc2)O]2 (7), boratetraferrocenylcyclotrisiloxane (C6H5)B(OSiFc2)2O (8), and diboratetraferrocenylcyclotetrasiloxane [(C6H5)B(OSiFc2)O]2 (9) with ferrocenyl (Fc = Fe(η-C5H4)(η-C5H5)) substituents at silicon have been prepared from the reactions of Cp2Zr(NMe2)2 and PhBCl2 with diferrocenylsilanediol Fc2Si(OH)2 (3) and tetraferrocenyldisiloxanediol [Fc2SiOH]2O (5). The compounds were characterized by mass spectrometry, elemental analysis, UV–vis, IR, Raman, and multinuclear NMR spectroscopy, as well as single crystal X-ray diffraction. Thermogravimetric analysis and differential scanning calorimetry investigation of 6–9 showed that the cycles decompose before they can undergo any thermal ring-opening polymerization. In addition, no polymerization was detected in the presence of either KOSiMe3 or HOTf. The bulky ferrocenyl substituents on the Si atoms are likely to be at least partially responsible for the inability of these heterocycles to undergo ring-opening polymerization. Key words: heterocyclosiloxanes, ferrocenyl.

A Deep Blue Organic Light Emitting Diodes Characteristic of Isomerically-Featured Phosphine Oxides Containing N-Phenyl Benzimidazole

2020 ◽  
Vol 20 (8) ◽  
pp. 4657-4660
Author(s):  
Kyeong Hyeon Kim ◽  
Jae Hyeok Lee ◽  
Dong-Eun Kim ◽  
Hoon-Kyu Shin ◽  
Burm-Jong Lee
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Light Emitting Diodes ◽  
Organic Light Emitting Diodes ◽  
Phosphine Oxides ◽  
Scanning Calorimetry ◽  
Light Emitting ◽  
Deep Blue ◽  
Organic Light

An isomeric series of phosphine oxides with N-phenyl benzimidazole such as 2-DPPI, 3-DPPI and 4-DPPI were synthesized for organic light emitting diodes (OLED). The thermal properties of DPPI isomers were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). OLED devices using DPPI isomers as the emitting material were fabricated, which configuration was ITO/MoOx [30 nm]/NPB [500 nm]/DPPI [300 nm]/Alq3 [200 nm]/Liq[10 nm]/Al [120 nm]. The emitting colors of the devices were respectively a deep-blue (430 nm, 4-DPPI) and greenish-yellows (510–580 nm, 3-DPPI and 530 nm, 2-DPPI). In particular, the emitting color of 4-DPPI device was not changed during the alteration of applied voltages (6.5–11.5 V), and the CIE coordinate was a satisfactory deep-blue (0.161, 0.101).

Sign in / Sign up

Export Citation Format

Share Document