Thermogravimetric analysis standards

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. 

Nitrogen adsorption was performed at -196 °C in a Micromeritics ASAP 2010 volumetric instrument. The samples were outgassed at 80 °C prior to the adsorption measurement until a 3.10 3 Torr static vacuum was reached. The surface area was calculated by the Brunauer-Emmett-Teller (BET) method. Micropore volume and external surface area were evaluated by the alpha-S method using a standard isotherm measured on Aerosil 200 fumed silica [8]. Powder X-ray diffraction (XRD) patterns of samples dried at 80 °C were collected at room temperature on a Broker AXS D-8 diffractometer with Cu Ka radiation. Thermogravimetric analysis was carried out in air flow with heating rate 10 °C min"1 up to 900 °C in a Netzsch TG 209 C thermal balance. SEM micrographs were recorded on a Hitachi S4500 microscope. 

Thermogravimetric Analysis When aspirin (USP reference standard) was heated at 20°/min. and a N2 flow of 20 cc/min.,no weight loss was observed at less than 130°.46... 

The PSI element of both the OSHA PSM Standard and the EPA RMP regulation can be improved by requiring the inclusion of all existing information on chemical reactivity. Examples of such information are chemical reactivity test data, such as DSC, thermogravimetric analysis (TGA), or accelerating rate calorimetry and relevant incident reports from the plant, the corporation, industry, and government. OSHA and EPA should require the facility to consult such resources as Bretherick s Handbook of Reactive Chemical Hazards,Sax s Dangerous Properties of Industrial Materials, and computerized tools (e g., CHETAH, The Chemical Reactivity Work Sheet). 

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. 

Preparation and Characterization of Lanthanide and Actinide Solids. Standard crystalline lanthanide and actinide phosphates were prepared by literature procedures (16-18) and characterized by X-ray powder diffraction, FTIR spectroscopy, and thermogravimetric analysis (TGA). Europium was used as an analogue of the trivalent actinides. Metal-phytate solids were generated by mixing Eu(III), U(VI), or Th(IV) nitrate solutions with 0.1 M phytic acid at pH 5 and metal.phytate ratios of 1 1 2 1, and 4 1. The metal phytates precipitated immediately. The resulting slurries were stirred at 85 °C for 30 days and sampled periodically for analysis of the solids by TGA, X-ray powder diffraction, and FTIR. The rate of phosphate release to the solution was monitored colorimetrically. 

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

A thermogravimetric analysis performed on sodium cephalothin (Eli Lilly reference standard P-89448) showed no weight loss until 154 C at 154 G weight loss begins resulting in decomposition. The measurement was performed under nitrogen sweep at a heating rate of 5 C/min. 

A thermogravimetric analysis of VCR sulfate (Lilly reference standard lot P-89453) was run using the Du Pont 950 Thermogravimetric Analyzer at a heating rate of 5° 0. 

Total ash content in leather can be measured by the standard test methods ASTM D2617-96 or by thermogravimetric analysis (TGA). 

A variation of these methods, in which the volume of gas evolved in a vacuum at a fixed temperature is measured, is also in common use. This approach is particularly useful when treating long-term, relatively mild thermal effects and the compatibility of explosives with other materials. Still other techniques for determining thermal stability are differential thermal and thermogravimetric analysis. These are coming into more common use, but are not yet standardized with respect to the explosive azides. 

Figure 3 shows a thermogravimetric analysis performed on the two molding compounds. The scans show that the molding compound based on the stable bromine CEN has a 15-20°C increase in thermal degradation temperature over the standard compound. Even though the stable bromine CEN is more thermally stable than standard resins, it still supplies the bromine necessary to achieve the desired flame retardancy properties. 

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. 

The optimal calcination method for zeolite beta was established by thermogravimetric analysis using a PL-Thermal Sciences STA 1500 apparatus. Chemical compositions of the zeolites were determined by atomic absorption spectroscopy on a Varian AAIO spectrometer after dissolution of the samples in hydrofluoric acid. The structure was confirmed by x-ray diffraction on a Siemens D-5000 diffractometer and with infrared spectroscopy on a Mattson Instruments Galaxy 2000 spectrometer. Total surface area, micropore area and micropore volume of the samples were determined by argon adsorption on a Micromeritics ASAP 200M volumetric analyzer using standard techniques. Crystal diameters were determined by scanning electron microscopy. 

Synthesized powders were calcined and characterized by standard techniques of thermogravimetric analysis, BET specific surface area measurements, and particle size determination by sedigraphy, as well as X-ray diffraction, and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) for microchemical analyses. To... 

Characterization of Polymers. The characterization of polymers Ifi - 21 was mainly spectroscopic in nature, FTIR and NMR, but some thermal analyses were also performed. The thermal analyses consisted of differential scanning calorimetry, DSC, and thermogravimetric analysis, TGA. Although the thermal analyses were in no way exhaustive, a few interesting features were found in the different polymers. The molecular weights of samples were examined by GPC and are based on polystyrene standards. 

Standard test method for environmental stress-cracking of ethylene plastics Insulating and sheathing materials of electric and optical cables - Common test methods - Part 4-1 Methods specific to polyethylene and polypropylene compounds - Resistance to enviromnental stress cracking - Measurement of the melt flow index - Carbon black and/or mineral filler content measurement in polyethy-lene by direct combustion - Measurement of carbon black content by thermogravimetric analysis (TGA) - Assessment of carbon black dispersion in polyethylene using a microscope... 

The rubber has to satisfy a number of criteria. First it should meet the general standard of physical properties laid down by the customer. To demonstrate compliance the first five batches of compound are subjected to the full specification tests to which are added rheometer and thermogravimetric analysis (TGA). These last two provide a production marker that will show conformity for the cure rate and to composition. They are rapid tests and allow bought in compoimds to be used with a high level of confidence provided that the supplier of the compound has been audited and found to conform to the required standard. 

Standard Malaysian rubber Tun Abdel Razak Research Centre N-Tef -butyl-2-benzothiazole sulfenamide Thermogravimetric analysis Tetramethyl thiuram disulfide Tetramethyl thiuram monosulfide Zinc 2-ethyl hexanoate... 

Standard Test Method for Constant-temperature Stability of Chemical Materials Standard Test Method for Arrhenius Kinetic Constants for Thermal Un.stable Materials Standard Test Method for Rapid Thermal Degradation of Solid Electrical Insulating Materials by Thermogravimetric Method Standard Test Method for Autoignition Temperature of Liquid Chemicals Standard Test Method for Specific Heat of Aircraft Turbine Lubricants by Thermal Analysis Standard Test Method for Linear Thermal Expansion of Solid Materials by Thermodilatometry... 

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