Which Plastics Are Recyclable?
by 3devo on Apr 16, 2020 3:02:00 PM
Plastic recycling is essential to sustainable living, but not all plastic materials can be recycled. In this blog post, we will explore the different types of plastics, how to recognize them, and the challenges associated with recycling.
In our previous blog post, we introduced you to our recycling journey and the mini-series we created for you on our YouTube channel. If you missed it, we recommend you check it out first before continuing on with this blog.
Which plastic materials can and cannot be recycled?
As you probably know, there are different types of plastic materials, and not all can be recycled. In this blog post, we are going to dive deeper into the different types that are out there and how you can recognize them.
There are 7 types of plastic materials; PETE or PET, HDPE, V or PVC, LDPE, PP, PS, and Other / Miscellaneous Plastics. Let's take a closer look at each type:
For most plastic consumables, you can recognize the type of plastic used by an indented icon of each plastic code stated below.
1. PETE or PET – Polyethylene Terephthalate
PET is the most common plastic material name nowadays. It’s used mostly in beverage bottles, oven–tray detergent, and cleaning product bottles. It is also used for the finishing of objects such as liquid crystals, displays, carpets, clothes, guitars, and pianos. Therefore, this material is suitable for recycling into filament; however, it absorbs odors and flavors from foods and liquids stored in it, which can prevent you from being able to recycle PET into filament. Furthermore, the plastic is designed for blow-molding, not extrusion (it does not flow easily inside an extruder).
2. HDPE – High Density Polyethylene
Another common plastic material is HDPE, which is known for having a low risk of leaching into foods and or liquids. This material is mostly used in the making of children's toys, yogurt cups, milk jugs, shampoo bottles, and other similar products. Recycled HDPE is mostly turned into pens, plastic lumber, plastic fencing, picnic tables, and bottles. This material is suitable for recycling into filament. However, it is not easy to turn into filament; it flows easily but requires special cooling.
3. V or PVC – Polyvinyl Chloride
PVC plastics contain very harmful chemicals that have been linked to various diseases. This material is usually used for the making of plumbing pipes, tiles, windows, and medical equipment. Due to the fact that this material has harmful chemicals, it is not recommended to recycle it yourself. PVC only gets recycled by specialized programs that recycle it into flooring, paneling, and roadside gutters.
4. LDPE – Low-Density Polyethylene
This material is a very safe and clean plastic. It is recognized by its flexible and thin texture. It is commonly found in household items like grocery bags, plastic wraps, frozen food containers, and food-holding bottles. LDPE is recyclable but not recommended to recycle into filament due to its behavior in the molten state and the shape of the items it usually comes in (grocery bags being a good example of something painful to shred). Recycled LDPE is usually found back in garbage cans, paneling, furniture, flooring, and bubble wrap.
5. PP – Polypropylene
Another known safe plastic is PP. This material has a sturdy texture, and it is commonly found back in Tupperware, syrup bottles, medicine bottles, and yogurt containers. It is also heat resistant as it is also used in making microwavable food containers. PP is suitable for recycling into filament (depending on the item you want to recycle), and it is usually recycled into heavy-duty items like pallets, ice scrapers, rakes, and battery cables.
6. PS – Polystyrene
This material is your everyday plastic, found in beverage cups, plastic utensils, insulation, packing materials, egg cartons, and disposable dinnerware. Although some would say that it is notorious for leaching and poor recyclability, we actually managed to recycle it into filament. Polystyrene is the material we used in our recycling video, and therefore, we can recommend you recycle your PS objects into filament. However, it is a possibility that random PS items could react differently and, therefore, work differently as well,
7. Other / Miscellaneous Plastics
SPI 7 is seen as all kinds of plastic that do not fall in the 1 to 6 category. Miscellaneous plastics are usually found back in nylon, baby milk bottles, sunglasses, computer casings, and compact discs. This is actually the most important category since it contains all of the interesting plastics. All of the cool engineering and high-performance ones would correspond to 7. It consists of an immense variety (Nylon6 and other types of nylon, PEEK, PEKK, PEI, TPU, PC, and many more). This category is a lot harder to define, but there is a lot of potential.
The Challenges of Recycling Different Plastics
Recycling plastics comes with its set of challenges. For instance, plastics like PEEK, PET, etc., come in various grades, and not all can be easily extruded and printed. Additionally, parts made from commodity plastics (1 to 6, with a few in 7) are often originally injection-molded, which complicates their compatibility with extrusion recycling. However, regardless of the plastic type, the recycling methodology remains consistent, involving purity of the batch, shredding to an even size, and finding appropriate settings for successful extrusion.
Next Steps: Shredding the Plastic Correctly for Extrusion
Having gained insight into different plastic types and their recycling challenges, our next focus is on shredding the plastic correctly to enable successful extrusion. That step will be made more accessible with our GP20 Hybrid Plastic Shredder.
Our Plastic Shredder is an innovative solution for plastic recycling, featuring an intelligent feeding system and interactive display for easy and efficient recycling of various plastic waste. Combining a smart plastic shredder with an integrated granulator, the GP20 Hybrid simplifies the recycling process, making it accessible and convenient. With its user-friendly interface, automated settings, and enhanced safety features, this shredder empowers individuals and businesses to take charge of their recycling efforts, contributing to a greener and more sustainable future. Check it out here:
As we continue our recycling journey, it's crucial to understand the diversity of plastic materials and their recycling potential. By recognizing the different plastic types and their specific challenges, we can take informed steps towards a more sustainable future. Join us next week as we explore the art of shredding plastic for successful extrusion. Together, let's positively impact our environment by embracing the possibilities of plastic recycling.
Please remember to recycle responsibly and sort your collected plastic to facilitate the next steps of our recycling journey. Together, we can make a significant difference!
Additional Resources and Contact Information
If you are still left with some unanswered questions, we recommend you visit our webpage, which is dedicated to the polymer pyramid. You can also download all material guides in just one PDF file on that same webpage. It is also always possible to contact us and to speak with one of our material experts.
We hope to see you back next week. In the meantime, sort out your collected plastic so we can move on to the next step together!
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