Meaning
International standardized test methods establish thermogravimetric analysis techniques to measure thermal degradation, filler content and composition in synthetic polymers. Analytical testing laboratories execute ISO 11358 to evaluate material mass changes as a function of temperature under controlled atmospheres. The test determines precise quantities of volatile organic content, polymer resin degradation and residual inorganic filler fractions.
Thermogravimetric Procedure
Test specimens undergo controlled heating ramps inside nitrogen or air atmospheres while sensitive microbalances record mass changes. Executing ISO 11358 generates thermogravimetric curves that show distinct degradation steps for different polymer formulation ingredients. Temperature settings identify initial thermal decomposition thresholds and organic additive volatilization points.
Precise atmosphere control prevents unwanted oxidation during primary decomposition phases.
Material Characterization
Weight loss steps correlate directly with specific component breakdown temperatures within multi-ingredient compounds. Analysts calculate carbon black content, inorganic filler loading and total polymer fraction from high-temperature residues. Distinguishing carbon black from organic polymer requires switching from inert nitrogen to oxidizing air environments at specified temperatures.
Quality Control
Compounding operations utilize thermogravimetric results to verify additive loadings and monitor lot-to-lot formulation consistency. Testing validates whether regrind or virgin resin compounds meet specified inorganic mineral targets. Deviations in residual mass indicate dosing errors during compounding or raw material contamination.
