Key Differences Between PP and PE
Both are from the polyolefin family, but each is produced for different properties and different applications. Which is preferred in which case?
Chemical structure
PP (polypropylene) is produced from the propylene monomer, and PE (polyethylene) from the ethylene monomer. Both belong to the polyolefin family, but their chain structures differ — PP's chain carries a methyl side group, which generally makes the material stiffer and gives it a higher melting temperature.
Stiffness and melting temperature
PP is typically stiffer than PE and has a higher melting temperature (PP melts at around 160-170°C, PE at around 105-135°C depending on density).
PE itself splits into two groups by density: AYPE (low-density) is more flexible and lower-density, common in film applications. YYPE (high-density) is stiffer and preferred for pipe and rigid packaging applications.
Which one, in which case?
PP: stands out in applications requiring strength and heat resistance, such as injection-molded parts, yarn/fiber, packaging closures and woven sacks.
AYPE: preferred for applications requiring flexibility, such as shopping bags, shrink film and lamination film.
YYPE: preferred for drinking water/sewage pipes, rigid containers and structural parts.
Suitable formulations exist in both materials for food-contact use, but approval should always be confirmed from the specific grade's own technical data (food-contact suitability field) — not assumed from generalization.
Related product group
See the related spec tables in our catalog.
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