Thermal analysis allows the study of the sample weight variation when there is an increase of temperature. This analysis can give us information about the thermal stability of a material, chemical reactions, solvents evaporation and reduction or oxidation of materials
we measure the weight, differential scanning calorimetry (DSC) and differential thermal analisys (DTA) of a sample considering time and temperature
The sensitivity of the balance is 0.07 micrograms. The furnace can operatefrom room temperature to 1,400ºC. The analyzer may work in several atmospheres such as oxygen, air, argon and hydrogen ( diluted at 5% in Ar), at ambient pressure and using typical flow rates of 70 cm3 / min.
We can also measure the energy absorbed and released when a sample is heated, frozen, or kept at constant temperature(power compensation DSC).
This technique is very useful to determine fusion or decomposition temperatures, phase transitions in crystals and amorphous solids, identification of polymorphs and also permits the identification of the molecular conformations as, for example, single polymer chain folding. This information is very helpful to explain the interaction between specific molecules and study the activity of drugs, cosmetics, etc.
Experiments can be made in the range of temperatures between 110 y 950 K , and very small amount of sample is needed (1-2 mg) to have reliable results
Surface area (BET), porosimetry and chemical adsorption
Gas adsorption measurements. The equipment measure the adsorption of nitrogen gas at liquid nitrogen temperature.We can determine the surface area of the sample and the size distribution of porosity
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