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Abstract
Thermoplastic masterbatches are a complex blend of the base thermoplastic resin, a pigment and a range of additive materials. End use applications of masterbatches include agricultural film, packaging film, injection moulding of small and large bottles, boxes and crates and extrusion of pipe and sheet. Thermal analysis is a very useful tool for the characterisation of the physical properties of both masterbatches and finished product. This report will show the use of differential scanning calorimetry (DSC) to identify the melt profiles of masterbatches and to determine oxidative stability. Thermogravimetric analysis (TG) is very useful for the determination of the composition of masterbatches, for the study of batch to batch variability and for a comparison of a material with competitive products. The use of High Resolution TGA (Hi-Res TGA) will be shown to give greater resolution between overlapping weight loss steps leading to better quantification of components within the masterbatch when compared to conventional TG.
Abstract
Effects of ethylene content and maleated EPDM content on the thermal stability and degradation kinetics of ethylene propylene diene monomer (EPDM) have been studied using high resolution thermogravimetric analysis (Hi-Res TGA) and Modulated TGA (MTGA). Modulated TGA shows that EPDM degradation is complex, with activation energy of degradation increasing throughout the degradation. Values from both dynamic and constant heating rate experiments are in good agreement with each other and with the literature value. However, the dynamic heating rate experiment shows that if the difference of peak temperature of components in a system is less than 5°C, Hi-Res TGA does not resolve them.
Abstract
Polyamide-6-block-polybutadiene copolymers have been prepared by the anionic polymerization of ɛ-caprolactam in presence of α,ω-dihydroxy terminated polybutadiene. TG, Hi-Res™ TGA, DSC, TMDSC and DMA techniques have been applied. The suitability of the methods used to determine the content, thermal stabilities and glass transition temperatures of the components constituting the block copolymer is discussed.
Abstract
The aim of this paper is to review current applications for thermal methods within the pharmaceutical industry as well as to present some early work on potential applications for two new thermal methods: Hi-Resolution Thermogravimetric Analysis and Modulated Differential Scanning Calorimetry.
Abstract
Divalent transition metal nitroprussides form a family of microporous materials which lose their crystallization water (coordinated and zeolitic) below 100°C and then remain stable up to above 150°C. The dehydration process of representative samples in their stable phases was studied by thermo-gravimetry (TG) and differential scanning calorimetry (DSC). The copper complex dehydrates in a single step through a practically irreversible process. For cadmium and cobalt complexes the water evolution on heating takes place in two stages. The first one, where only zeolitic waters are removed, is dominated by a diffusion mechanism while, during the loss of the strongly bonded waters (second stage) the material framework effect is added. The involved activation energy and its dependence on the conversion degree were estimated evaluating the thermo-gravimetric data according to an isoconversion model.
thermal methods. Methods and instrumentation Thermal decomposition was studied using a TA Instruments 2950 Hi-Res TGA instrument interfaced with a Thermal Analyst control unit. For dynamic runs a heating rate of 5 °C min −1 was
. 14. Practical notes for Hi-Res ® TGA-2950 . New Castle : TA Instruments Inc. 1990 . http://www1.chm.colostate.edu/Files/CIFDSC/TGA-MS.pdf . 15. TA-023. Thermal applications notes
