Fatigue Energy Dissipation in Polypropylene via Untreated Calcium Carbonate

Assumption under test

Mineral fillers uniformly reduce fatigue life in polypropylene by increasing brittleness.

Why this assumption matters

Commodity plastics are evaluated almost exclusively under static tensile and impact tests. Fatigue resistance is inferred, not measured, despite its dominance in real-world failure.

Edge of Practice experiment

Injection mold polypropylene containing 15 wt% untreated calcium carbonate. Subject samples to low-strain cyclic flexural fatigue for 10⁵–10⁶ cycles.

Failure condition

Earlier crack initiation or reduced fatigue life relative to neat polypropylene.

Pass criterion

≥30% increase in cycles to crack initiation compared to neat polypropylene.

Status: Final · Mid-Cycle