PP is widely favored for its durability, heat resistance, and flexibility. It's commonly used for child-resistant and tamper-evident caps. It can handle mechanical stress and works well with sealing inserts like pressure-sensitive liners or induction foil.
PS, on the other hand, is often used for transparent or decorative caps. It's rigid, cost-effective, and offers excellent dimensional stability. While it's more brittle than PP, it suits applications where clarity and appearance are prioritized.
Understanding the properties of each plastic helps buyers make informed decisions. For functional, everyday use-especially in healthcare or food sectors-PP is often the better choice. For promotional or cost-sensitive packaging, PS provides a reliable alternative.