How To Differentiate Between The Most Common Types Of Plastic

Plastic is an important component of many items, including water bottles, combs, various containers, etc, but not all of them are made the same and often we get confused when it comes to recycling. Knowing how to differentiate between them will really help and make a difference, as well as the SPI codes, allowing you to make a more informed decision about recycling.

Since we have produced almost 9.1 billion tons of plastic, it is important that, for the sake of the environment, to know the different types of plastic, what they are used for, as well as identification codes for each of them. This will help you make an informed decision when it comes to choosing the appropriate plastic for a certain product as well as what to do when it comes to recycling.

Recycling Codes for Plastic

Understanding the meaning of a plastic item’s code can help you make a more informed decision for the longevity of a product, your health, and the environment. In addition, it’s important to become familiar with an item’s code so as to be able to better classify the different types of plastic so that you can make a more informed decision when sorting plastic for recycling.

What Are the Different Types of Plastic?

When walking through your house or office you are unlikely to only be surrounded by one type of plastic. There is a large variety. It’s easy to just look at one item and see the plastic as “plastic”, but different types are made differently, and are used for different things. Here are the 7 different classification types.

Number 1 – Polyethylene Terephthalate (PETE or PET)

Created in 1940, this plastic is one of the most commonly used types today. In the 70’s it was heavily commercialized and used for the first time to sell beverages such as Coca-Cola and Pepsi, boosting its prevalence in our society and environment.

Today PETE plastics makeup about 96% of all plastic bottles and containers in the US but are unfortunately poorly recycled. These plastics are recyclable and should be processed correctly so as to keep them out of landfills and cause less pollution.

Number 2 – High-Density Polyethylene (HDPE) 

Created in 1953 this plastic was made using catalysts and low pressure to create a high-density polyethylene. Initially, this was used for pipes in storm sewers, drains, and culverts, but is used for an even wider variety of products. The professionals behind explain that it is a strong and rigid material and is easily processable. This means that it is perfect for cutting, drilling, and even routing.

Due to the easily processable nature of HDPE, it is also the most commonly recycled plastic as it will not break under exposure to extreme temperature. Unfortunately, only around 12% of all HDPE products created in a year are recycled.

Plastic Number 3 – Polyvinyl Chloride (PVC) 

PVC is one of the oldest synthetic materials in industrial production and was accidentally discovered twice. Once in 1838 by a French physicist and again in 1872 by a German chemist.

It is one of the least recycled materials; typically less than 1% is recycled each year. It also has various negative connotations surrounding it, so please recycle your PVC.

Plastic Number 4 – Low-Density Polyethylene (LDPE) 

Similar to HDPE, LDPE was actually the first polyethylene to be produced. It is less dense than HDPE, which is why it’s considered a different material for recycling.

Packaging and containers made from this type of plastic make up about 56% of all plastic waste, about ¾ of which come from the household. Fortunately, many recycling programs are evolving to curb this issue and are making special provisions to stop LDPE from ending up in landfills.

Plastic Number 5 – Polypropylene (PP) 

PP was discovered in 1951. At the time, the inventors were trying to convert propylene into gasoline but discovered instead a new catalytic process for making plastics.

Less than 3% of PP products are recycled in the US, which means a lot of this plastic is created, but only a small amount is recycled.

Plastic Number 6 – Polystyrene or Styrofoam (PS) 

Polystyrene was discovered in 1839. It is a lightweight, easy to form the material and is often used to form takeaway containers. Due to its effortless breakability, it is single-use plastic and litters beaches everywhere. It fills up about 35% of landfill sites in the US.

Plastic Number 7 – Miscellaneous Plastics

The remaining plastics include polycarbonate, polylactide, acrylonitrile butadiene, fiberglass, acrylic, styrene, and nylon. There are plenty of differences in the plastics classified as miscellaneous by recycling programs, but the commonality is that these plastics are not easy to recycle. They are very strong and require extremely high temperatures to melt them down.

Different plastics have different purposes. It is important to know the various types of plastics and how to recycle them once you no longer have a use for them. Doing so will help you make the right use of this resource for your personal and professional needs.

About the author

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Benjamin Noah

Benjamin is a professional blogger and marketer, who frequently writes about custom packaging, technologies, news and health to help businesses understand and adapt new ways to reach and inspire their target audience.