Identification of Elastomers by Thermal Analysis

1972 ◽  
Vol 45 (1) ◽  
pp. 329-345 ◽  
Author(s):  
A. K. Sircar ◽  
T. G. Lamond
Keyword(s):  
Molecular Structure ◽  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Chemical Composition ◽  
Thermal Degradation ◽  
Thermooxidative Degradation ◽  
Scanning Calorimetry ◽  
Multiple Peaks ◽  
Thermal Patterns ◽  
Structure Configuration

Abstract Degradation of polymers by thermal and thermooxidative reactions is associated with either evolution or absorption of heat which can be followed by differential scanning calorimetry. In the present investigation, DSC thermographs of elastomers between 0° C and 500° C in nitrogen (thermal degradation) and oxygen (thermooxidative degradation) were used for identification of the elastomers from their degradation patterns. Based on the nature of the thermographs of the raw polymers in nitrogen, the elastomers studied may be divided into the following three main groups: (a) those which show an exotherm, (b) those which show an endotherm, and (c) those which show multiple peaks of endo- or exotherms. Identification is aided in some cases by the thermographs in oxygen as well as by the physical transitions. The nature (exo- or endo-) and shape of the thermal patterns and the temperature domain at which the reactions take place depend on the molecular structure, configuration, chemical composition, and nature of the substituents as well as on the environment. Consequently, thermal and thermooxidative degradation curves may be used as a “fingerprinting” device which can identify many polymers, difficult to identify by other methods.

scholarly journals A thermal degradation study of Y and La methanesulfonates

2006 ◽  
Vol 71 (8-9) ◽  
pp. 905-915
Author(s):  
Moura de ◽  
Jivaldo Matos ◽  
Farias de
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Differential Thermal Analysis ◽  
Thermal Degradation ◽  
Degradation Process ◽  
Oxide Formation ◽  
Scanning Calorimetry ◽  
Degradation Study ◽  
Thermogravimetric Data ◽  
Thermal Degradation Process

The synthesis, characterization and thermal degradation of yttrium and lanthanum methanesulfonates is reported. The prepared salts were characterized by elemental analysis and infrared spectroscopy. The thermal degradation study was performed using thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC).Using the thermogravimetric data, a kinetic study of the dehydration ofY and Lamethanesulfonates was performed employing the Coats-Redfern and Zsak?methods. It was verified that under heating, yttrium and lanthanum methanesulfonates undergo three main processes: dehydration, thermal degradation and oxide formation. Furthermore, depending on the nature of the atmosphere, i.e., inert or oxidant, the thermal degradation process could be endothermic (N2) or exothermic (air).

scholarly journals Thermal analysis: basic concept of differential scanning calorimetry and thermogravimetry for beginners

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Nurul Fatahah Asyqin Zainal ◽  
Jean Marc Saiter ◽  
Suhaila Idayu Abdul Halim ◽  
Romain Lucas ◽  
Chin Han Chan
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Commercial Application ◽  
Scanning Calorimetry ◽  
Teaching Activities ◽  
Sample Decomposition ◽  
Calibration Baseline

AbstractWe present an overview for the basic fundamental of thermal analysis, which is applicable for educational purposes, especially for lecturers at the universities, who may refer to the articles as the references to “teach” or to “lecture” to final year project students or young researchers who are working on their postgraduate projects. Description of basic instrumentation [i.e. differential scanning calorimetry (DSC) and thermogravimetry (TGA)] covers from what we should know about the instrument, calibration, baseline and samples’ signal. We also provide the step-by-step guides for the estimation of the glass transition temperature after DSC as well as examples and exercises are included, which are applicable for teaching activities. Glass transition temperature is an important property for commercial application of a polymeric material, e.g. packaging, automotive, etc. TGA is also highlighted where the analysis gives important thermal degradation information of a material to avoid sample decomposition during the DSC measurement. The step-by-step guides of the estimation of the activation energy after TGA based on Hoffman’s Arrhenius-like relationship are also provided.

scholarly journals Combined thermal analysis of plant oils

2021 ◽  
Author(s):  
Kinga Tamási ◽  
Kálmán Marossy
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Low Temperature ◽  
Glassy State ◽  
Mechanical Analysis ◽  
Plant Oils ◽  
Scanning Calorimetry ◽  
Natural Plant ◽  
The Moment ◽  
Current Reversal

AbstractThe paper deals with the study of seven selected natural plant oils. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and thermally stimulated discharge (TSD) methods were used. It has been found that most of the oils tested are in a glassy state at low temperature and have multiple transitions in the low temperature range. DSC shows complex melting-like processes or glass transition. For both DMA and TSD, the scaffold supportive method was used and found as a suitable one. DMA and TSD proved more sensitive than DSC and revealed at least two transitions between − 120 and − 40 °C. In the case of three oils (argan, avocado and sunflower), current reversal was observed by TSD; this symptom cannot be fully explained at the moment.

scholarly journals Films Based on a Blend of PVC with Copolymer of 3-Hydroxybutyrate with 3-Hydroxyhexanoate

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 270
Author(s):  
Evgeniy V. Belukhichev ◽  
Vera E. Sitnikova ◽  
Evgenia O. Samuylova ◽  
Mayya V. Uspenskaya ◽  
Daria M. Martynova
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Environmental Pollution ◽  
Polyvinyl Chloride ◽  
Polymer Films ◽  
Thermomechanical Analysis ◽  
Packaging Materials ◽  
Packaging Film ◽  
Scanning Calorimetry ◽  
Environmental Friendliness

Polymeric packaging materials are one of the factors of environmental pollution. Reducing the environmental burden is possible by increasing the environmental friendliness of packaging materials. In this work, we study polymer films based on polyvinyl chloride (PVC) with a copolymer of 3-hydroxybutyrate with 3-hydroxyhexanoate P (3-GB) (3-GG) with different component ratios. The process of processing blends in the process of obtaining a packaging film is considered. The optical characteristics of the obtained films are determined. Thermal analysis of the obtained films was carried out using the differential scanning calorimetry (DSC), TGA, and thermomechanical analysis (TMA) methods. The degree of gelling of the resulting mixture was determined. It is shown that PHB has miscibility with PVC.

Human cytokines characterized by dielectric thermal analysis, thermogravimetry, and differential scanning calorimetry

2012 ◽  
Vol 111 (3) ◽  
pp. 1707-1716 ◽  
Author(s):  
Salaam Saleh ◽  
Druthiman Reddy Mantheni ◽  
Manik Pavan Kumar Maheswaram ◽  
Susan Moreno-Molek ◽  
Tobili Sam-Yellowe ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Scanning Calorimetry ◽  
Dielectric Thermal Analysis ◽  
Human Cytokines

The thermal degradation of μ-Diphenylacetylene-bis(tricarbonylcobalt)

1973 ◽  
Vol 26 (8) ◽  
pp. 1791 ◽  
Author(s):  
RS Dickson ◽  
LJ Michel
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Carbon Monoxide ◽  
Thermal Degradation ◽  
Organic Compounds ◽  
Degradation Mechanism ◽  
Scanning Calorimetry ◽  
Organic Products ◽  
Suitable Temperature ◽  
Degradation Reaction

The thermal decomposition of Co2(CO)6(PhC2Ph) has been investigated in detail. Differential scanning calorimetry was used to determine the most suitable temperature range for the study. At 180�, Co2(CO)6(PhC2Ph) decomposes to form cobalt, carbon monoxide, tetraphenylcyclopentadienone, hexaphenylbenzene, and other organic compounds. Variation in the temperature, the time, and the solvent used for the degradation reaction causes significant changes in the yields of the organic products. An investigation of the effects of adding stoichiometric amounts of free alkyne, tetra-phenylcyclopentadienone, and hexaphenylbenzene has been initiated in an attempt to understand the degradation mechanism.

Thermal Analysis of Aluminum Alloys

2019 ◽  
Author(s):  
Daniel Larouche
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Quality Control ◽  
Aluminum Alloys ◽  
Isothermal Calorimetry ◽  
Curve Analysis ◽  
Cooling Curve ◽  
Scanning Calorimetry ◽  
Cooling Curve Analysis ◽  
Scientists And Engineers

Thermal analysis is applied on aluminum alloys by researchers to investigate mainly phase transformations, while it is regularly used for quality control purposes in industry. Techniques like cooling curve analysis, differential thermal analysis, differential scanning calorimetry, and isothermal calorimetry are amongst those most frequently used by scientists and engineers. These techniques will be described, and a mathematical description of the results will be developed. State-of-the-art quantification methods applied on aluminum alloys will be presented and criticized based on specific examples taken from the literature.

scholarly journals Synthesis, Mesomorphism and the Optical Properties of Alkyl-deuterated Nematogenic 4-[(2,6-difluorophenyl)ethynyl]biphenyls

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4653
Author(s):  
Jakub Herman ◽  
Piotr Harmata ◽  
Michał Czerwiński ◽  
Olga Strzeżysz ◽  
Marta Pytlarczyk ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Mass Spectrometry ◽  
Differential Scanning Calorimetry ◽  
Optical Properties ◽  
Liquid Crystalline ◽  
Near Infrared ◽  
Synthesis And Characterization ◽  
Molecular Approach ◽  
Scanning Calorimetry

The synthesis and characterization of new deuterated liquid crystal (LC) compounds based on phenyl tolane core is described in this paper. The work presents an alternative molecular approach to the conventional LC design. Correlations between molecular structure and mesomorphic and optical properties for compounds which are alkyl-hydrogen terminated and alkyl-deuterium, have been drawn. The compounds are characterized by mass spectrometry (electron ionization) analysis and infrared spectroscopy. They show enantiotropic nematic behavior in a broad temperature range, confirmed by a polarizing thermomicroscopy and differential scanning calorimetry. Detailed synthetic procedures are attached. Synthesized compounds show a significantly reduced absorption in the near-infrared (NIR) and medium-wavelength infrared (MWIR) radiation range, and stand as promising components of medium to highly birefringent liquid crystalline mixtures.

scholarly journals Thermal stability and thermal decomposition of sucralose

2018 ◽  
Vol 39 (4) ◽  
pp. 21
Author(s):  
Gilbert Bannach ◽  
Rafael R. Almeida ◽  
Luis G. Lacerda ◽  
Egon Schnitzler ◽  
Massao Ionashiro
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Thermal Decomposition ◽  
Differential Thermal Analysis ◽  
Infrared Spectroscopy ◽  
Scanning Calorimetry ◽  
Thermoanalytical Techniques ◽  
Thermal Stability Of

Several papers have been described on the thermal stability of the sweetener, C12H19Cl3O8 (Sucralose). Nevertheless no study using thermoanalytical techniques was found in the literature. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC) and infrared spectroscopy, have been used to study the thermal stability and thermal decomposition of sweetener.

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