Recycled Polyester from PET Plastics
Similarities to Polyester
Note that due to the similarities between polyester and recycled polyester, no terms previously defined in the polyester section will be defined here.
History
Only twenty years after polyester burst onto the fabric scene, polyester was being made from plastic bottles made of PET [1]. Since then, dozens of companies have begun manufacturing polyester and touting their "recycled" label. Unfortunately, like many other fabrics that claim to be recycled, very few pieces of clothing are 100% recycled. In this case, a lower percentage of recycled polyester is due to the dyeing process detailed below.
Manufacturing
Production of recycled polyester is almost identical to virgin polyester, except for the first few steps:
1) Bottles are collected and shredded into chips to remove traces of food before they are sent overseas (bottles may or may not be sorted by color in this step depending on the company)
2) Once the chips arrive at their factory destination, they are sorted by color
3) The sorted chips are sent to a bath, and since caps and other materials float above the desired plastic, they are skimmed off top
4) To remove labels, chips are sent to caustic chemical bath to remove the labels and glue residues
5) To dry the now wet plastic, the chips are sent to oven that rotates for about 10 hours
6) Chips are then mixed with lighter plastics to make a more even-colored, white cloth. At this stage, chlorine dyes are often used to make a more uniform color [2].
7) The clean, dry chips are now sent to rotating screw that rotates and melts the plastic at 270°C (518°F) and melted down into a thick syrupy solution.
After this point, there is little difference between the recycled polyester process and the virgin polyester process. This may cause many to wonder, is recycled polyester really so green if a lot of the same dyeing and energy processes are being used?
Note: For a wonderful video documenting the above process, I highly recommend this National Geographic video on how plastic bottles become clothing.
Note that due to the similarities between polyester and recycled polyester, no terms previously defined in the polyester section will be defined here.
History
Only twenty years after polyester burst onto the fabric scene, polyester was being made from plastic bottles made of PET [1]. Since then, dozens of companies have begun manufacturing polyester and touting their "recycled" label. Unfortunately, like many other fabrics that claim to be recycled, very few pieces of clothing are 100% recycled. In this case, a lower percentage of recycled polyester is due to the dyeing process detailed below.
Manufacturing
Production of recycled polyester is almost identical to virgin polyester, except for the first few steps:
1) Bottles are collected and shredded into chips to remove traces of food before they are sent overseas (bottles may or may not be sorted by color in this step depending on the company)
2) Once the chips arrive at their factory destination, they are sorted by color
3) The sorted chips are sent to a bath, and since caps and other materials float above the desired plastic, they are skimmed off top
4) To remove labels, chips are sent to caustic chemical bath to remove the labels and glue residues
5) To dry the now wet plastic, the chips are sent to oven that rotates for about 10 hours
6) Chips are then mixed with lighter plastics to make a more even-colored, white cloth. At this stage, chlorine dyes are often used to make a more uniform color [2].
7) The clean, dry chips are now sent to rotating screw that rotates and melts the plastic at 270°C (518°F) and melted down into a thick syrupy solution.
After this point, there is little difference between the recycled polyester process and the virgin polyester process. This may cause many to wonder, is recycled polyester really so green if a lot of the same dyeing and energy processes are being used?
Note: For a wonderful video documenting the above process, I highly recommend this National Geographic video on how plastic bottles become clothing.
Not So Green
Like virgin polyester, recycled polyester has the exact same chemical make up. PET (polyethylene terephthalate, essentially the monomer in polyester) is also used to make plastic water bottles. Given the alarming rate of plastic bottle sales (see chart below), it is shocking that more PET plastic bottles aren't being recycled. In 2011 alone, approximately 802 thousand tons of PET plastic bottles were recycled nationwide in the United States alone, but 1.9 million tons of PET plastic bottles were wasted [3]. That's a recycle rate of only about 42%.
However, many people hail polyester as the next big eco-friendly fabric because it utilizes recycled PET and has the potential to be reused over and over again without wearing out like natural fibers. Yet this argument is flawed because of the fact that many polyester producers mix their recycled PET with virgin PET, thereby contributing to the unsustainable practice of using petroleum based products.
To understand exactly why polyester manufacturers dilute recycled polyester with virgin polyester, you must understand two things:
1) On the technical side, recycled polyester does not have uniform color, and a lot of dye must be used to make it an acceptable color, making the process less cost effective.
2) On the economical side, cheap production cost is the reason manufacturers like polyester so much anyways.
Therefore, while claiming to recycle in the interest of ecological benefits, many companies operate with the larger cost of production in mind and have minimal, if any, benefit to the environment as a result.
What You Can Do
While recycled polyester is not perfect, it is still better than virgin polyester from an environmentalist's point of view, for cutting a pollutant, unsustainable energy out of the picture is almost always the best policy. Given the choice, chose recycled polyester.
However, the best thing we as individuals can do is to recycle our clothing, especially fabrics that don't biodegrade easily like polyester. Companies are beginning to realize that this is both economically and ecologically beneficial, and recently H&M has begun collecting clothing from customers in an effort to be more earth-conscious.
Nevertheless, the single best thing you can do is to simply buy less clothes. By investing in your clothing, you'll save money in the long run and use less of the earth's resources while you're at it!
Like virgin polyester, recycled polyester has the exact same chemical make up. PET (polyethylene terephthalate, essentially the monomer in polyester) is also used to make plastic water bottles. Given the alarming rate of plastic bottle sales (see chart below), it is shocking that more PET plastic bottles aren't being recycled. In 2011 alone, approximately 802 thousand tons of PET plastic bottles were recycled nationwide in the United States alone, but 1.9 million tons of PET plastic bottles were wasted [3]. That's a recycle rate of only about 42%.
However, many people hail polyester as the next big eco-friendly fabric because it utilizes recycled PET and has the potential to be reused over and over again without wearing out like natural fibers. Yet this argument is flawed because of the fact that many polyester producers mix their recycled PET with virgin PET, thereby contributing to the unsustainable practice of using petroleum based products.
To understand exactly why polyester manufacturers dilute recycled polyester with virgin polyester, you must understand two things:
1) On the technical side, recycled polyester does not have uniform color, and a lot of dye must be used to make it an acceptable color, making the process less cost effective.
2) On the economical side, cheap production cost is the reason manufacturers like polyester so much anyways.
Therefore, while claiming to recycle in the interest of ecological benefits, many companies operate with the larger cost of production in mind and have minimal, if any, benefit to the environment as a result.
What You Can Do
While recycled polyester is not perfect, it is still better than virgin polyester from an environmentalist's point of view, for cutting a pollutant, unsustainable energy out of the picture is almost always the best policy. Given the choice, chose recycled polyester.
However, the best thing we as individuals can do is to recycle our clothing, especially fabrics that don't biodegrade easily like polyester. Companies are beginning to realize that this is both economically and ecologically beneficial, and recently H&M has begun collecting clothing from customers in an effort to be more earth-conscious.
Nevertheless, the single best thing you can do is to simply buy less clothes. By investing in your clothing, you'll save money in the long run and use less of the earth's resources while you're at it!