Quality Control Tests for Polymer Compounds: MFI, Izod & Tensile Explained
Three tests, run on nearly every batch of polymer compound, tell you whether the material will process consistently and perform as specified in the finished part.
Melt Flow Index (MFI)
MFI measures how easily a polymer melt flows under a standard temperature and load, expressed in grams per 10 minutes. It's the fastest way to check batch consistency - a shift in MFI often signals a change in resin, additive dosage or processing history that could affect downstream performance.
Izod Impact Test
The Izod impact test measures how much energy a notched sample absorbs before breaking under a swinging pendulum, giving a standard measure of toughness. It's commonly run at both room temperature and low temperature, since many plastics behave very differently in cold conditions.
Tensile Strength & Elongation
Tensile testing pulls a standard sample until it breaks, measuring strength (maximum stress before failure) and elongation (how much it stretches before breaking) - both critical for confirming a compound meets its stiffness and ductility specification.
Why Batch Testing Matters
Running these tests on every production batch, not just at initial development, is what allows a compounder to guarantee consistency to customers and catch process drift before it reaches a customer's production line.
Siya Polymer provides MFI, impact and tensile test data with batches on request, backed by in-house quality testing.
Talk to Our Quality Team →
