What is Polyester?
The British scientists John Whinfield and James Dickson first invented polyester cloth in 1941 in England. After World War II was over, in 1945, the United States company DuPont bought the right to make polyester and by 1950 a factory in Delaware was beginning to actually make it.
People make polyester out of oil. You take the oil, which is a kind of very big hydrocarbon molecule, and break it down into two smaller molecules, ethylene glycol and dimethyl naphthalate, both still made entirely of oxygen, carbon, and hydrogen atoms. Dimethyl terephthalate is an ester, and ethylene glycol is a kind of alcohol. When you mix the ester and the alcohol together, they form molecules with both positive and negative charges, and the charges force the molecules to line up in chains of crystals that hold together as long fibers.
Recycling plastic bottles into polyester thread
The polymerized material comes out of the machine in long ribbons, and you cut the ribbons into little chips and let them harden. Then you melt the chips again and push the goo out through little holes to make thinner ribbons, and wind the thinner ribbons around spools. Then you heat the thinner ribbons and stretch them out to about five times their original length, to make them thin enough to use as thread to weave cloth.
Since the 1960s, polyester has been the cheapest kind of cloth, and almost half of all the world's clothing is made of polyester. You are probably familiar with polyester mainly from team shirts like for soccer or basketball.
Because we make polyester out of oil, polyester clothing will get more expensive as we run out of oil and it gets more expensive.