Ash Content

testing

The percentage of inorganic residue remaining after complete combustion of a plastic material at high temperature, indicating the level of inorganic fillers, additives, or contaminants.

In Simple Terms

Ash content tells you how much non-plastic material is in your resin. When you burn a plastic sample completely, what's left behind is ash - mostly from fillers like calcium carbonate, talc, or glass fibers. Higher ash content means more inorganic additives.

Why It Matters

Ash content directly affects material properties, processing behavior, and cost. It helps verify filler loading levels, detect contamination, ensure batch consistency, and validate supplier specifications. Critical for quality control in resin trading and processing.

Technical Details

Determined by ASTM D5630 or ISO 3451, samples are heated to 575-900°C in air until complete oxidation. Typical ranges: unfilled resins <0.1%, calcium carbonate filled compounds 5-40%, glass-filled grades 10-50%. Results correlate with density, stiffness, and thermal properties.

Real-World Examples

Glass-filled nylon resin verification

A 30% glass-filled PA66 should show 25-28% ash content. Lower values indicate insufficient glass loading, affecting mechanical properties and pricing.

Calcium carbonate filled PP quality check

CaCO3-filled polypropylene with specified 20% filler loading should yield 18-20% ash content. Deviations indicate formulation inconsistencies.

Virgin resin contamination detection

Virgin HDPE showing 2% ash content instead of expected <0.1% indicates contamination with filled materials or processing aids, requiring investigation.