Thermogravimetric Analysis (TGA): A Complete Guide to Methods & Applications
Thermogravimetric Analysis (TGA) measures changes in a material’s mass as a function of temperature or time under a controlled atmosphere. This versatile thermal analysis technique provides critical data on composition, thermal stability, decomposition kinetics, and volatile content for the plastics, pharmaceutical, chemical, rubber, food, and semiconductor industries. For companies seeking TGA testing at a US-based testing lab, Infinita Lab provides comprehensive thermal analysis through its accredited laboratory network.
How TGA Works
A precision microbalance continuously weighs a small sample (typically 5–20 mg) as it is heated at a controlled rate in an inert (nitrogen, argon) or reactive (air, oxygen) atmosphere. Mass loss steps correspond to specific thermal events: moisture evaporation, solvent loss, polymer decomposition, filler residue, and ash content. The derivative curve (DTG) shows the temperature at which the maximum mass-loss rate occurs for each event.
Common TGA Applications
Compositional Analysis of Polymers
TGA separates and quantifies polymer components in a single run: moisture and volatiles (25–200°C), polymer matrix decomposition (200–600°C in nitrogen), carbon black burn-off (switching to air at 600°C), and inorganic filler/ash residue. This provides a complete compositional breakdown for the plastics industry.
Thermal Stability Assessment
The onset temperature of decomposition defines a material’s maximum processing or service temperature. TGA data guide parameter selection for extrusion and molding operations, and validate material suitability for high-temperature applications.
Moisture and Volatile Content
TGA accurately measures moisture, residual solvent, and volatile plasticizer content in pharmaceutical excipients, food products, coatings, and polymer resins—critical data for quality control and shelf-life prediction.
Filler and Ash Content
TGA quantifies inorganic filler content (glass fiber, calcium carbonate, talc, silica) in compounded plastics, complementing ASTM D5630 (ash content) testing for incoming inspection and batch verification.
Testing Standards
Key standards include ASTM E1131 (compositional analysis by TGA), ASTM E1868 (loss-on-drying), ASTM D6370 (rubber composition), ISO 11358 (general TGA method), and USP <731> (loss on drying for pharmaceuticals).
Infinita Lab: Your Material Testing Partner
Contact Infinita Lab for TGA Testing and enjoy major benefits like end-to-end testing management, faster turnaround, and reduced administrative burden. Gain confidence in accurate results and reduced stress in vendor coordination. Enhance your reputation for product reliability and innovation. Engineers and R&D managers can focus on core work rather than testing logistics.
Looking for a trusted partner to achieve your research goals? Schedule a meeting with us, send us a request, or call us at (888) 878-3090 to learn more about our services and how we can support you. Request a Quote
Frequently Asked Questions (FAQs)
What does TGA measure? TGA measures mass changes in a sample as it is heated, providing data on moisture content, volatile components, polymer decomposition temperature, filler/ash content, and overall thermal stability.
What is the difference between TGA and DSC? TGA measures mass changes (decomposition, volatilization), while DSC measures heat flow (melting, crystallization, glass transition). Together, they provide a comprehensive thermal characterization of materials.
What ASTM standards cover TGA? ASTM E1131 covers compositional analysis, ASTM E1868 covers loss-on-drying, ASTM D6370 covers rubber analysis, and ASTM E2550 covers thermal stability by TGA.
How does TGA determine polymer composition? Sequential mass loss steps in TGA correspond to different components: moisture, volatile additives, polymer matrix, carbon black, and inorganic fillers. Each step’s percentage quantifies that component’s contribution.
What atmosphere is used for TGA testing? An inert atmosphere (nitrogen or argon) is used for pyrolysis and decomposition studies. An air or oxygen atmosphere is used for oxidative stability, carbon content determination, and complete combustion to ash residue.
