Thermogravimetric analysis:

Interpretation of TGA Curves:

TGA curves are typically classified into seven types according to their shapes. Figure 23.03 shows schematic of various types of TGA curves.

Figure 23.03: Schematic of various types of TGA curves.

• Curve 4: Multistage decomposition: This curve reveals the multi-stage decomposition processes as a result various reactions.

• Curve 5: Similar to 4, but either due to fast heating rate or due to no intermediates.

• Curve 6: Atmospheric reaction: This curve shows the increase in mass. This may be due to the reactions such as surface oxidation reactions in the presence of an interacting atmosphere.

• Curve 7: Similar to curve 6, but product decomposes at high temperatures. For example, the reaction of surface oxidation followed by decomposition of reaction product(s).