The Difference Between Polyethylene (PE) & Polypropylene (PP)

A start-up bakery and coffee shop owner recently contacted us to source branded cold drink packaging. When we discussed designs for her new PET cups over email, she replied and asked if I was finding her a cup for pets or humans! There are many types of plastic, and it could seem confusing to an industry newcomer. Different varieties of plastic and poly materials are needed for different applications, from stretch film to tape, plastic sheeting to strapping. While we source a wide range of packaging materials, poly bags are our most requested item.

Below, we’re covering two of the most common types of plastic — polyethylene (PE) vs. polypropylene (PP) — and the critical differences between them.

Polyethylene (PE):

• Known for its crystal-clear transparency, customers can see the contents inside, making them a leading poly in food packaging.
• Soft, flexible, and good tensile strength.
• Generally less expensive than PP.
• Available in various thicknesses and sizes and are therefore used for packaging a wide range of products, including baked goods, groceries, and various consumer goods.

Polypropylene (PP):

• Offer high clarity and excellent moisture resistance, but not as much clarity as PE.
• Good heat resistance and can withstand higher temperatures compared to PE.
• Often used for packaging products with higher fat content or require additional moisture protection, such as snacks, candies, and baked goods.
• Used in various industries, including food packaging, textiles, and medical applications.

Sustainability of PE and PE

Both materials are recyclable, varying by density. Polypropylene can be recycled up to four times. High-density polyethylene can be recycled up to ten times, whereas low-density polyethylene can only be recycled once, making high-density polyethylene a far more sustainable material. Although they are reusable, neither is compostable or biodegradable, unlike other eco-friendlier films on the market.

Having the correct poly bag or film for your application makes all the difference, and arming yourself with that information upfront protects you from costly mistakes early on. If you require packaging, ForeFront Packaging leverages 40 years of experience in food manufacturing to assist customers with selecting the right material for their packaging requirements.