RECYCLED POLESTER (rPET)
How can the polyester in your sweater be so soft if it is made from hard plastic bottles?
Both polyester and plastic bottles are made of the same material - polyethylene terephthalate, PET for short.
Used bottles are sent to a recycling center, where the plastic bottles are shredded to relatively big bits and then manually sorted out by color, mainly separating the clear plastic from the colored one: clear transparent plastic can be made into material that can be dyed, making it more valuable.
The bigger plastic bits are shredded again to tiny bits and then sent through two different baths: the first bath through water where the shredded bottle caps, made of lightweight plastic unsuitable for polyester production, floats. A worker can then strain them off the top. A second bath, containing caustic soda removes all the stickers.
The clean but wet plastic shreds must then go through the rotary dryers to slowly dry out for about ten hours.
The dry plastic shreds are then sent through an Archimedes screw, heated to 270° degrees Celsius, melting the shreds and force the now liquid plastic through lots of very fine holes to make continuous filaments, several times finer than a human hair.
After cooling down, these filaments solidify and are cut to the desired length, giving origin to very fine and soft fibers which are then blended with the Cashmere, Wool, and Tencel™ fibers and spun together into the yarn.
Recycling plastic bottles give a second life to a material that is not biodegradable and would otherwise end up in landfill or the ocean.
A yearly average of 8 million tons of plastics ends up in the oceans, on top of the 150 billion tons that are already there (NGO Ocean Conservancy). And these plastics will actually stay there for an average of at least 450 years... although It can really take some plastic bottles THOUSAND years to biodegrade!
At this rate, no wonder there will be already more plastic than fish in the ocean by 2050.
As for landfill, 23 million tons of plastic have been disposed of, in USA's landfills in 2015 alone (USA Environmental Protection Agency).
In addition to removing plastic waste away from the environment, the resulting recycled polyester has actually the same quality as polyester from virgin oil and require 59% less energy to produce (Swiss Federal Office for the Environment, 2017 study), thus reducing CO2 emissions and oil/gas consumption.
POLYESTER (rPET) recycling facts:
PETCORE
TEXTILE EXCHANGE'S RECYCLED POLYESTER ROUND TABLE