How to Test the Thermal Stability of Hot Melt Adhesive Web in Industrial Settings?

Hot Melt Adhesive Web are widely used in industries such as packaging, automotive, and textiles due to their fast bonding capabilities and versatility. However, their performance heavily depends on thermal stability, especially when exposed to prolonged high temperatures in industrial settings. Proper testing ensures reliability, safety, and cost-efficiency in production.
Why Thermal Stability Matters
Thermal stability determines how well an adhesive maintains its structural integrity, viscosity, and bonding strength under heat. Poor thermal resistance can lead to:
Degradation – Reduced adhesive strength and premature failure.
Charring or Oxidation – Formation of residues that clog application equipment.
Inconsistent Performance – Variability in bonding quality, increasing waste and downtime.
Key Methods for Testing Thermal Stability
1. Thermogravimetric Analysis (TGA)
TGA measures weight loss as a function of temperature, identifying the point at which the adhesive begins to decompose. This helps determine the maximum safe operating temperature before degradation occurs.
2. Dynamic Mechanical Analysis (DMA)
DMA evaluates viscoelastic properties (e.g., storage modulus, loss modulus) under thermal stress, revealing how the adhesive behaves under mechanical load at elevated temperatures.
3. Heat Aging Tests
Samples are subjected to prolonged exposure at controlled temperatures (e.g., 24–168 hours) in ovens, followed by:
Peel/Shear Strength Testing – Assesses retained bond strength.
Melt Flow Index (MFI) Analysis – Checks viscosity changes, indicating thermal degradation.
4. Rheological Testing
Measures viscosity and elasticity under varying shear rates and temperatures, ensuring consistent flow properties during application.
Simulate Real-World Conditions – Test at temperatures slightly above expected operational ranges.
Monitor Thermal Cycling Effects – Repeated heating/cooling can impact adhesive performance.
Combine Multiple Tests – A single method may not capture all failure modes; TGA + DMA provides comprehensive insights.