TGA Analysis

testing

Thermogravimetric Analysis (TGA) is a thermal analysis technique that measures weight loss of a material as a function of temperature or time, used to determine decomposition temperatures and filler content.

In Simple Terms

TGA analysis heats up a plastic sample while continuously weighing it. As temperature increases, components like moisture, additives, and the polymer itself decompose and evaporate, causing weight loss. This creates a curve showing exactly when and how much material is lost at each temperature.

Why It Matters

TGA analysis is crucial for quality control in resin trading, helping verify filler content, thermal stability, and material purity. It enables processors to select resins with appropriate decomposition temperatures for their applications and helps identify contamination or degradation issues.

Technical Details

TGA typically operates from ambient temperature to 800°C in controlled atmospheres (nitrogen, air, or oxygen). The technique measures sample weight with microgram precision while following programmed heating rates (usually 10-20°C/min). Results show onset decomposition temperature, peak decomposition rate, and residual ash content, providing quantitative data on thermal stability and composition.

Real-World Examples

Filler Content Verification

A resin trader receives a shipment of glass-filled nylon claiming 30% glass fiber content. TGA analysis shows 28% residual weight at 800°C, confirming the actual filler level matches specifications within acceptable tolerance.

Thermal Stability Assessment

An injection molder needs to process PVC at 200°C but TGA shows decomposition begins at 180°C, indicating the need for additional thermal stabilizers or lower processing temperatures to prevent degradation.

Contamination Detection

TGA analysis of a polypropylene batch shows unexpected weight loss at 150°C, revealing moisture contamination that could cause processing defects like splay marks or bubble formation during molding.