PP vs PET: Which Plastic Is Right for Your Packaging Project?

2026-10-17 OriginalChina Plastic Factory Editorial220

Summary: PP and PET dominate food and beverage packaging, but they behave very differently in moulding, barrier performance and recyclability. This guide compares them on the criteria buyers actually evaluate.

The short answer

Choose PET when you need clarity, carbonation retention or a premium shelf look for beverages. Choose PP when you need heat resistance, hinge performance or a low-cost rigid container that will be hot-filled or microwaved.

1. Thermal performance

PP homopolymer survives service temperatures up to about 100°C and can be hot-filled at 85-95°C without deformation. Standard PET softens near 70°C, so hot-fill PET requires heat-set tooling and a thicker wall. If your process includes pasteurisation or microwave reheating, PP is the safer baseline.

2. Barrier and shelf life

PET has roughly 5-10 times the CO2 barrier of PP, which is why carbonated drinks are almost universally PET. For oxygen-sensitive food, both materials need an EVOH or nylon tie layer, or a scavenger additive. For short shelf-life dry goods, the difference rarely justifies the cost gap.

3. Optical properties

Injection-grade PET produces a glass-clear container. PP is naturally translucent to opaque; clarified PP (random copolymer with clarifier) gets close to clear but still reads slightly hazy next to PET. If the product must be seen, PET wins on shelf.

4. Cost per part

PP resin is generally cheaper per kilogram, and PP parts are lighter because the material is less dense (0.90-0.91 g/cm³ versus 1.33-1.40 g/cm³ for PET). A 500ml PP tub typically costs less to mould than an equivalent PET jar, though the gap narrows once labels and closures are included.

5. Recyclability

Both are code 1 (PET) and code 5 (PP) streams with established markets in Europe and North America. Clear PET has the highest value per tonne. PP containers with full-wrap sleeves are harder to sort, so specify perforated or floatable labels if the brand has recycled content commitments.