True or false: Bio-based textile materials are less durable and of lower quality than fossil-based

What are the pros and cons of natural versus synthetic materials?

Materials are usually chosen based on the desired features. Synthetic fibres may have strength and endurance, or they can better transfer moisture and release sweat, for example. Natural fibre fabrics, on the other hand, may be better at draping well and providing warmth. 

Then again, there are many other factors at play as well. Synthetic fibres have the advantage that they can be modified already when the fibres are manufactured. For instance, it is possible to influence the cross-sectional shape and curliness of the fibre.

Are natural fibres always more sustainable than synthetic ones?

It is not evident. Production of bio-based polyester, for example, may have smaller carbon footprint than, say, cotton. Then again, not all bio-based materials are necessarily more sustainable than fossil-based. To determine this, the entire lifecycle of the material has to be assessed.

Do all bio-based textiles biodegrade? Can they start to rot while still in use?

The origin of the raw material doesn’t determine whether the material will biodegrade or not.

At their purest form, natural fibres like cotton or wool do biodegrade, but that may not be the case after several dyes or chemical treatments. On the other hand, there are fossil-based materials that can be biodegradable.

Polyester made with UPM’s wood-based mono ethylene glycol (MEG) is chemically identical to the conventional petroleum-based polyester. This is why it’s called a drop-in solution. It has the same properties and fulfils the same specifications that manufacturers are used to. It can be implemented both into existing polyester manufacturing processes and, once recycling of fabrics becomes feasible, recycling streams.

This also means that it won’t decompose or mold any more than fossil-based polyester.

Are new synthetic materials automatically of poorer quality?

On a general level, it may be safe to stick with existing materials but replace the fossil-based feedstocks with bio-based drop-in alternatives. Polyester has been used for decades, during which it has been optimised for several applications.

It would be unfair to judge any new material against polyester though – to reduce dependency on fossil-based polyester and water-intensive cotton, all solutions at hand are needed in making fashion materials more sustainable.

There are constant technological advances that bring about new materials and new ways of working with materials. Cellulose-based viscose and wood-based synthetic fibers are good examples of innovative solutions that can replace cotton and fossil-based materials.

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