Differential thermal analysis automated

Thermal analysis iavolves techniques ia which a physical property of a material is measured agaiast temperature at the same time the material is exposed to a coatroUed temperature program. A wide range of thermal analysis techniques have been developed siace the commercial development of automated thermal equipment as Hsted ia Table 1. Of these the best known and most often used for polymers are thermogravimetry (tg), differential thermal analysis (dta), differential scanning calorimetry (dsc), and dynamic mechanical analysis (dma). 

The application of dielectric constant techniques to thermophysical measurement of solids has been used for a number of years (114, 115). The early uses of the technique involved isothermal measurements employing bridge methods. Recently, techniques have been developed that permit the measurement of the dielectric constant of a solid as a function of temperature, in a manner similar to other TA techniques. Chiu (116) used the term dynamic electrothermal analysis (ETA) to describe the measurement of both the capacitance and the dissipation factor of polymeric samples. Nottenburget al (117) developed an automated technique that permitted the rapid determination of the dielectric properties of a substance over a wide range of temperature and frequencies. This technique, which was called dynamic dielectric analysis (DDA), was modified to measure concurrently the DTA curve of the sample as well (117, 118). This new technique was called dynamic dielectric analysis-differential thermal analysis, DDA-DTA,... 

The Qualitative determination of major crystalline phases was achieved using the Philips X Pert Pro automated diffractometer equipped with a Ge (111) primary monochromator. Chemical composition was determined by X-ray fluorescence (XRF) using the Philips Magix Pro (PW-2440). Thermal behaviour was determined by thermogravimetric and differential thermal analysis (TGA-DTA) with a Mettler Toledo 85 le device in oxygen operating at a ramp of 20 °C/min from room temperature to 1000 °C. 

Mathematical modeling of the cure process coupled with the automation of various thermal analytical instruments and Fourier Transform Infrared Spectroscopy (FT-IR) have made possible the determination of quantitative cure and chemical reaction kinetics from a single dynamic scan of the reaction process. This paper describes the application of FT-IR, differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) in determining cure and reaction kinetics in some model organic coatings systems. 

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