Is Polyester Plastic-Free?

What is Polyester?

Polyester is a synthetic polymer, polyethylene terephthalate, made by reacting petroleum-derived purified terephthalic acid (PTA) with monoethylene glycol (MEG). The resulting resin is the identical chemistry used for PET drink bottles. Melted and extruded into filament, that plastic becomes polyester fiber. So yes, unambiguously, polyester is plastic.

Fiber type

Synthetic thermoplastic (petroleum)

Source

Crude oil / natural gas (PTA + MEG)

Biodegradable

No

Sheds microplastics

Yes

How is Polyester made?

PTA and MEG are polymerized into PET chips, melted, and spun through spinnerets into continuous filament or cut into staple. The fiber is then textured, drawn, and finished. Nothing in the chain is plant-derived; it is a petrochemical process from start to finish.

How does Polyester perform?

This is why it dominates: cheap, strong, fast-drying, wrinkle- and shrink-resistant, holds color and shape, and takes performance finishes well. The cost is environmental. It is made from fossil feedstock, it persists for centuries, and laundering it releases microplastic fibers that end up in water, soil, and human tissue.

So, is Polyester plastic-free?

No. Polyester is not plastic-free because polyester is plastic. This is the clearest verdict in the glossary: PET fiber and PET bottle are the same polymer. Recycled polyester (rPET) reuses that plastic but is still plastic and still sheds microplastics. The only way to leave plastic behind is a different fiber, not a different grade of polyester. See plastic-free fabric for the fibers that qualify.

Where you see it: The majority of activewear, fast fashion, linings, fleece, and most performance blends.

The OHZEHN-TEX™ take

Polyester is the fiber a plastic-free brand is usually trying to design out. The reason it is hard to drop is performance: stretch, recovery, and fast drying. OHZEHN-TEX™ is our own bio-based performance fabric platform: bio-based nylon PA6.10 made from castor oil, with a bio-based stretch fibre made from sugarcane. See the full material logic in our plastic-free performance guide.

How much microplastic does polyester actually shed?

A lot, and it has been measured. In a controlled study of domestic washing machines (Napper and Thompson, Marine Pollution Bulletin, vol. 112, issue 1 to 2, pp. 39 to 45, 2016), a single six kilogram wash load of polyester released an estimated 496,030 microplastic fibers, with acrylic the worst synthetic tested at 728,789 fibers per load. A separate study (De Falco et al., Scientific Reports, vol. 9, article 6633, 2019) found that one polyester garment on its own can release up to roughly 250,000 fibers in a single wash. These are not trace amounts, they are hundreds of thousands of plastic fragments leaving one laundry cycle for the wastewater stream. DOI: 10.1016/j.marpolbul.2016.09.025 · DOI: 10.1038/s41598-019-43023-x

The reason this matters for the plastic-free question is what happens after the fiber leaves the machine. Because polyester is PET, what it sheds is a plastic microfiber that does not biodegrade. In a controlled laundering and degradation study (Zambrano et al., Marine Pollution Bulletin, vol. 142, pp. 394 to 407, 2019), polyester fibers plateaued and did not degrade under aerobic aquatic conditions, while cellulosic fibers such as cotton and rayon broke down over the same period. So polyester does not simply shed, it sheds a persistent microplastic that stays in the environment, which is exactly why designing it out beats trying to wash it more gently. DOI: 10.1016/j.marpolbul.2019.02.062

Where this fiber lands in production

Polyester shows up most in performance activewear sourcing, basics and blanks manufacturing, and bio-based swimwear fabric, and the standard that governs all of it is set out at manufacturing program.