I use it every day, but how much do I know about PET plastic?
Category (1) PET - Polyethylene terephthalate
How is PET produced?
PET is produced by combining ethylene glycol and terephthalic acid to form PET granules. These granules, when heated, turn into liquid and easily take the shape of our imagination.
At higher processing temperatures, PET crystallizes and becomes opaque, hardens and loses flexibility. This crystallized form of PET is commonly used for food packaging or containers that can be reheated in an oven or microwave.
PET can also be converted into fibres through a chemical and heat process, and when used for textiles, it is known as "Polyester." When PET is used for food or beverages, it is called "PET" or "PET resin," while an older version of the name was known as "PET-P."
This plastic is mostly used in the textile form as "Polyester," and today more than 80% of our wardrobe contains polyester.
PET is also famous as a packaging material for water, drinks, juices, salad dressings, cooking oils, shampoos, liquid hand soaps, and even tennis balls, among many other products and packaging. Specific grades of PET are used for "take-out" food containers and containers for frozen and prepared foods that can be heated in the microwave.
History of PET
PET was first discovered in America in the mid-1940s by DuPont chemists who were researching polymers that could be used to produce textile fibres, which were named "Dacron." Through this experimentation, in the late 1950s, a new method of stretching PET layers was also discovered, resulting in PET film that is extensively used for videos, photography, X-ray films, and packaging films.
In the 1970s, advanced technology enabled PET to be transformed into strong, lightweight, and break-resistant bottles. Today, PET is one of the most widely used categories of plastic in the market. More than half of the world's synthetic fibres are made from PET, and all single-use bottles contain PET material.
- The PET bottle was patented in 1973 by chemist Nathaniel Wyeth;
- The first PET bottle was recycled in 1977;
- Since 1978, manufacturers have reduced the weight of 2-litre PET bottles by 29%, from 68 grams to 48 grams;
- Recycling 1 ton of PET containers saves 5.6 cubic meters of landfill space;
- In 2005 an average family generated 19.05 kg of PET plastic bottle waste;
- Fourteen half-litre PET bottles contain enough fibres to produce an XXL short-sleeve shirt;
- Fourteen half-litre PET bottles are needed to build 0.09 square meters of carpet;
- Sixty-three half-litre PET bottles are needed to produce a sweater;
- Fourteen half-litre PET bottles are needed to produce a ski jacket;
- Eighty-five half-litre PET bottles are needed to produce a sleeping bag.
Why is PET used so much?
- Lightweight: It is produced at a low cost and requires less energy for transportation;
- Safe: It does not break easily;
- Convenient for carrying;
- It can be recycled and reused many times (although it is not widely recycled);
- It can be shaped into various forms, allowing brands to build their identity;
- Flexible: Manufacturers can switch from one shape or size to another.