What Does “Poly” Mean?

What does poly mean? If you frequent our website or worked with us over the years, you’ve probably heard us mention poly bags once or twice…or 500 times. We can’t help it! We love plastic bags and want to share the convenience of poly bags with the world. But unless you’re as obsessed with poly bags as we are, you probably are a little unsure as to what the “poly” in bags means. It actually refers to polyethylene and polypropylene.

What is Polyethylene?
The sturdier of the two “polys”, polyethylene (Wikipedia) is a type of polymer that is classified as a thermoplastic. This means that it can be melted into a liquid as it returns to a solid state. It is a found in many household items such as food wrap, shampoo bottles, milk jugs, toys, and our favorite—plastic bags! In addition to these handy household items, polyethylene is used in products that contain plastic components like artificial knee and hip replacement parts, bulletproof vests, and even the flooring for ice skating rinks.

What is Polypropylene?
The melting point for polypropylene (Wikipedia) is much higher than other plastics, so it is often used in products that are dishwasher or microwave safe. Polypropylene is the more durable of the two plastics and is used in heavy-duty industrial plastic bags, as well as plastic hinges, or tops for travel mugs. It is very easy to add dyes to and is often used as fiber in carpeting.

View our list of Custom Poly Bag Products to find out just what we do with our poly!