Plastics: What’s Recyclable, What’s Trash, and Why?

Plastic is a compound polymer that can be shaped or molded into a massive variety of valuable products, from bags to bicycle seats. What surprises most consumers about plastic is that there isn’t just one type of plastic but several, from polyethylene terephthalate (PET or PETE) and polystyrene (PS) to polypropylene (PP) and several more. Different types of plastic are used for different products and purposes.

Now, the average consumer would likely have a difficult time discerning the differences between the types of plastics. To answer the question of what plastics are recyclable, what are trash, and why, you need to look more closely at the two primary categories of plastic.

The Key Differences Between Plastics

To answer the question of which plastic is recyclable, and which isn’t, you must first determine what type of plastic you’re dealing with between the two main categories: thermoplastics and thermosetting plastics. One of the two is nearly infinitely recyclable, while the other isn’t. Let’s take a look at the main differences between these two categories of plastic.

Thermoplastics

Used in a wide variety of injection molding and extrusion projects, thermoplastic can be softened, melted, and reused when they reach the end of their useful lives. In short, they can be continuously recycled and made into new products.

One thing to note is that thermoplastics typically have the prefix “poly” (meaning “many”) in their names. Thus, a thermoplastic using styrene is polystyrene, and one using ethylene is polyethylene.

Thermosetting Plastics

When formed, thermosetting plastics can withstand much higher temperatures than thermoplastics. They’re also much more durable, and amazingly, they can be used as replacements for metal parts such as gears.

However, the most significant difference between thermosetting plastics and thermoplastics is this: you can’t recycle thermosetting plastic. Even with the application of heat, you can’t recycle thermosetting plastics.

As we’ve seen, most plastic products fall into two major categories: thermoplastics and thermosetting plastics. When it comes to what’s recyclable, what’s trash, and why, thermoplastics are almost infinitely recyclable, while thermosetting plastics can’t be recycled at all. Thus, the differences between plastics comes down to these two main categories. Each has its place and uses, of course. Only thermoplastics, however, win the recycling game, ready to be turned into other products when their previous uses have come to an end.