What are the effects of hydrolysis on the structural integrity of polypropylene?

Hydrolysis, a chemical reaction involving water, significantly impacts the structural integrity of polypropylene (PP), a widely used thermoplastic polymer. When exposed to moisture, especially at elevated temperatures or in acidic/alkaline environments, polypropylene undergoes hydrolysis, leading to chain scission and molecular weight reduction. This degradation weakens mechanical properties such as tensile strength, flexibility, and impact resistance.

The extent of hydrolysis depends on factors like polymer crystallinity, additive composition, and environmental conditions. Stabilizers and hydrophobic coatings can mitigate these effects, but prolonged exposure inevitably compromises PP's durability. Understanding hydrolysis is crucial for applications in packaging, automotive, and construction, where moisture resistance is critical. Proper material selection and protective measures are essential to prolong polypropylene's lifespan in humid or wet environments.