Most industrial thermoplastics can be recycled when they’re clean and kept separate. HDPE (#2) and polypropylene (#5) are the easiest and most in-demand for post-industrial recycling, followed by PET (#1) and LDPE (#4). PVC, polystyrene and mixed or multi-layer plastics are harder and have fewer buyers. Wide-spec resin, which falls outside a producer’s tight specification, is not waste and is usually sold for less demanding uses. Whether a given load actually gets recycled depends less on the resin than on how clean and well sorted it is.
Key takeaways
- HDPE and polypropylene production scrap is the easiest industrial plastic to recycle, and it’s what AP&J mainly processes.
- Recycling codes 1 through 7 tell you the resin family, not whether a recycler will take it.
- Contamination and mixed resins cause more rejected loads than the type of plastic itself.
- Wide-spec and off-spec material is still usable plastic and can often be recycled or sold.
Why some plastics recycle more easily than others
Almost all packaging and molded parts are thermoplastics, which means they soften when heated and harden again as they cool. In principle they can all be ground and remelted. In practice, a few things decide whether a plastic gets recycled:
- Demand. A recycled resin only gets recycled if a molder or compounder wants to buy it. HDPE and polypropylene have large, steady markets.
- Purity. Mixing two resins, or leaving labels, metal or residue in the load, lowers the quality of the regrind and can make it unusable.
- Heat stability. Some resins hold their properties well through reprocessing. Others, like PVC, can break down and need careful handling.
- Construction. Multi-layer films, laminates and parts with several bonded materials are hard to separate, so they’re harder to recycle.
Post-industrial scrap has a large advantage on all four counts. It’s usually one known resin, clean and produced in steady volume. That’s why factory scrap is recovered at much higher rates than household plastic.
Common industrial plastics and how they recycle
| Resin (code) | Where you see it in industry | How it recycles |
|---|---|---|
| PET (#1) | Bottles, thermoformed trays, strapping, clamshells | Widely recycled, especially bottle grade; needs to be clean and dry, and thermoformed PET is less in demand |
| HDPE (#2) | Bottles, drums, crates, pallets, pipe, totes | One of the easiest to recycle; strong demand for regrind |
| PVC (#3) | Pipe, profiles, siding, wire coating | Recyclable in clean industrial streams but must be kept away from other resins; fewer buyers |
| LDPE / LLDPE (#4) | Stretch wrap, shrink film, bags, liners | Clean, clear film recycles well; dirty or printed film is harder |
| Polypropylene (#5) | Caps, closures, automotive parts, containers, yard signs | Easy to recycle from clean production scrap; good demand |
| Polystyrene (#6) | Trays, cups, protective foam | Possible but limited; foam is bulky and expensive to move |
| Other (#7) | ABS, nylon, polycarbonate, blends, multi-layer | Depends entirely on the specific material and whether it’s clean and separated |
The resin code molded into a part identifies the plastic family. It doesn’t promise that a recycler will accept it. Ask your recycler about each material you generate.
HDPE and polypropylene: the workhorses
AP&J mainly processes HDPE and polypropylene, and for good reason. They’re two of the most common resins in manufacturing and packaging, they hold up well through grinding and remelting, and molders and compounders use a lot of regrind made from them.
HDPE scrap from blow molding, injection molding and pipe extrusion, as well as worn HDPE crates, drums and pallets, can be ground and sold back into new molded products. Polypropylene scrap from caps, closures, containers and automotive parts recycles the same way. One example: polypropylene campaign yard signs. AP&J has accepted them at no charge, and in 2021 the Fort Worth Star-Telegram reported that signs we collected were going to be made into one-gallon paint bottles.
AP&J takes HDPE, PP, LDPE film, PET, ABS and regrind in nearly any form, including parts, purgings, bales and film. If you’d like to know more about what happens to these resins once they leave your dock, see our guide to plastic grinding and toll processing.
PET, LDPE and the harder materials
PET
PET is the most familiar recycled plastic because of drink bottles. Bottle-grade PET has a strong market. Other PET items, like thermoformed trays and clamshells, are recyclable in principle but have weaker demand. PET also has to be dried before it’s remelted, which adds a step.
LDPE and stretch film
Warehouses and distribution centers generate a lot of stretch wrap and shrink film. Clean, clear film baled on its own is recyclable. Film mixed with tape, labels, paper or food residue is much harder to place.
PVC and polystyrene
Clean PVC production scrap can be recycled, but even small amounts of PVC can ruin a batch of another resin, so it must be kept fully separate. Polystyrene, especially foam, is light and bulky, which makes collection costly compared to its value.
Medical and engineering plastics
Plants that mold medical device components or engineering parts often use polypropylene, polycarbonate, polystyrene and ABS. Clean production scrap from those lines, like runners, rejects and changeover material, can be recycled in the same way as other post-industrial plastic. Used medical items are a different matter, because anything that has contacted patients or bodily fluids is regulated medical waste and doesn’t belong in a plastic recycling stream.
What wide-spec plastic is, and why it isn’t waste
Resin producers make plastic to tight specifications for properties like melt flow, density and color. Material that falls outside those limits, for example during a grade change or a process upset, is sold as wide-spec or off-spec resin. It’s still good plastic. It simply doesn’t meet the narrow spec for its original grade.
Wide-spec resin is usually sold at a discount for applications that can tolerate more variation, such as many molded goods, crates, pipe and blends. Plants that end up with wide-spec material, or with off-spec parts from their own processes, shouldn’t treat it as garbage. Depending on the resin, it can be ground and sold, blended or put to use in a less demanding part. The waste problem only shows up when no one finds a home for it and it ends up in a dumpster.
How to get more of your plastic recycled
- List every plastic your plant throws away, by resin and roughly how much.
- Give each resin its own labeled container, and keep film separate from rigid scrap.
- Keep trash, metal, paper and wood out of plastic containers.
- Store scrap covered so it stays clean and dry.
- Ask your recycler which materials have value, which they’ll take at no cost and which they can’t place.
Material that can’t be recycled as plastic may still be kept out of the landfill through other routes. Our landfill diversion and commercial recycling services look at a plant’s whole waste stream rather than just one resin.
Frequently asked questions
What is the easiest industrial plastic to recycle?
Clean, single-resin HDPE and polypropylene production scrap are the easiest. They’re common, reprocess well and have steady demand from molders and compounders.
Does the number in the triangle mean a plastic is recyclable?
No. The resin identification code only says what family the plastic belongs to. Whether it gets recycled depends on whether a recycler has a market for that material in that condition.
Can mixed plastics be recycled?
Mixed plastics are much harder to recycle because different resins don’t blend well when melted. Separating materials at the plant, before they go into a container, is the most effective way to keep them recyclable.
Can AP&J take plastics other than HDPE and polypropylene?
HDPE and polypropylene are our main focus. If you have something else, call us with the resin, form and rough volume and we’ll tell you what we can take.
Not sure what your plant’s plastic is worth or whether it can be recycled? Call AP&J at (682) 841-1303 or send us the details through our contact form, and we’ll take a look.
