Thermogravimetric analysis calibration

Thermal Properties. The glass transition temperature (Tg) and the decomposition temperature (Td) were measured with a DuPont 910 Differential Scanning Calorimeter (DSC) calibrated with indium. The standard heating rate for all polymers was 10 °C/min. Thermogravimetric analysis (TGA) was performed on a DuPont 951 Thermogravimetric Analyzer at a heating rate of 20 °C/min. 

The thermal properties of benzoic acid were evaluated using simultaneous differential thermal analysis (DTA) and thermogravimetric analysis (TGA). This work was performed on a Shimadzu DT-30 Thermal Analyzer system, which was calibrated using indium standard. Using a heating rate of 10°C/min, the thermograms presented in Figure 3 were obtained. 

Thermogravimetric analysis can be perfonned with heating rates up to 108 K/min without significant temperature gradients inside small samples. An STA apparatus enabling a temperature calibration under the exact experimental conditions will give reliable process temperatures. This allows kinetic modelling without consideration of the enthalpy balance. 

TABLE I Thermogravimetric Analysis of Lactose Calibration Standards 48... 

A Perkin-Elmer TGA-7 instrument calibrated by Curie points of several metal standards has been employed for non-isothermal thermogravimetric analysis. The measurements were carried out at a desired heating rate (in the range of 3 - 40 K/min) in both inert (argon) and oxidizing (oxygen) atmospheres, as appropriate. 

In this chapter we present background principles of thermogravimetric analysis and the various measurement modes issues associated with and recommendations for calibration measurement and analysis methods for characterizing polymeric materials, including recommendations for how to perform a TGA experiment and kinetics. At the end of the chapter we present selected applications of actual industrial problems where TGA has been instrumental in their solution. 

TG analysis of pantoprazole sodium was conducted obtained using a TA Instruments model 951 thermogravimetric analyzer system, calibrated using indium. The thermograms were carried out at a heating rate of 10°C/min, the sample size used ranged 5 to 10 mg, and the samples were heated over a temperature range of 50°C to 400°C. 

The characterization of arsenobetaine was performed using element analysis, H NMR, mass spectrometry, thermogravimetric/thermodifferential analysis and separative methods such as HPLC, GC and CZE. From all the results obtained it was concluded that the maximum amount of water present in the solid (if stored and handled under dry atmosphere) is 1% (w/w). In addition, arsenic impurities represent less than 0.15% (w/w) other impurities can be neglected. Therefore, the arsenobetaine purity of the calibrant obtained is >98.9%. 

---