Thermogravimetric analysis (TGA) precisely measures a sample's mass as it is heated under a controlled temperature program and atmosphere. The resulting mass-versus-temperature profile reveals when and how much material is lost or gained, providing a quantitative compositional and thermal-stability fingerprint of the sample.

Because TGA responds only to changes in mass, it is well suited to characterizing:

• Volatile content — moisture, residual solvents, and other low-temperature losses
• Decomposition behavior — onset temperatures, thermal stability, and degradation steps
• Composition — relative fractions of volatiles, organic (polymer) content, carbon black, and inorganic filler or ash
• Mass-gain reactions — oxidation, adsorption, and chemisorption, distinguishable by running under inert versus oxidizing atmospheres

Run under nitrogen, air, or oxygen, TGA is a core tool for material identification, failure analysis, and characterizing unknown deposits and contaminants.