True or false: Bio-based synthetic fabrics can’t be recycled

What about the clothes fashion brands have labelled as 'recycled material’?

Most of the recycled cotton is not made from recycled clothes but so-called pre-consumer waste like cutting scraps from the factory. Recycled polyester, in turn, comes from recycled bottles. A staggering 99 percent of recycled polyester is made from PET bottles.

In the long run this is not very sustainable as it would be better to keep monomaterial bottles in the closed bottle-to-bottle recycling loop for as long as possible. 

At the moment, textile industry is solving the beverage industry’s waste problem, not its own. Most textiles are recycled into lower value products like cleaning rags and insulation material. One reason for this is that textiles are usually multimaterials, which means they consist of several different materials, the combination of polyester and cotton being the most typical one. For this reason, they are not suitable for chemical recycling yet but require mechanical recycling.

What’s wrong with the mechanical recycling?

In mechanical recycling fabrics are shredded, with all their dyes and chemicals included. Fibres get cut shorter in the process. This means the quality of the outcome is lower than in the original fabric.

In chemical recycling materials are broken into the molecular level, resulting in virgin raw materials to produce again polymer fibres that are as good as the original material.

How to design more sustainable, recyclable fabrics?

In mechanical recycling, you get what you give. The better the quality of the original material, the better the quality of recycled material as well.

Today’s textile producers face many demands: brands and consumers want clothes to perform in a variety of ways, from breathability to water resistance and fire safety. This leads to fabrics with a mixture of materials, dyes and other chemicals, that is difficult recycle.

Thus, any excessive dyes, treatments and layers should be avoided unless they are vital for creating durable fabrics.

The biggest challenge for the recycler is to know what’s in the material. Even if the label says 100 percent polyester, fabric may contain a mixture of different polyesters – while most people would assume this means entirely PET-based material. Things will get easier with the new EU regulation that requires all textile products to have digital product passports that indicate the origin of the materials.

How to make fashion more sustainable?

Polyester dominates the global textile market: nearly 60 percent of all fibres produced are polyester, and the share is growing steadily. Cotton holds the second place with an approximately 25 percent share. In most clothes these two are combined.

The entire industry is vigorously looking for recyclable, renewable or more sustainable alternatives to replace these materials and help curb greenhouse emissions. The greatest advances are likely to come from finding alternative sources for the existing materials.

One great alternative for fossil-based polyester is polyester containing UPM’s wood-based mono ethylene glycol (MEG). It is a drop-in solution that can be easily implemented into existing polyester manufacturing process as it is identical to currently used petroleum-based ingredients of the resin. This also means it can go into the same recycling streams as polyester. And there are high hopes that the chemical recycling possibilities for polyester will dramatically improve in the future. Currently several companies (BlockTexx, Syre and the likes) are developing chemical recycling solutions for polyester, cotton and the mix of the two.

Meanwhile, we all need to buy less and wear what we have for a longer time. As much as 80 percent of greenhouse emissions in the textile industry come from production of fibres and materials. If clothes are used for only a short period of time before they are disposed, enormous amount of raw materials and energy is wasted. 

These experts were interviewed for the story: Gerd Unkelbach and Sebastian Funtan (UPM Biochemicals), Katri Pylkkänen (Finnish Textile & Fashion)