Voice over
What do the strips used to wrap mummies and this boat's hull have in common?
Both are made of flax fibres. This plant material, highly-popular with Egyptians has never gone out of fashion and is even attracting new interest among industrial firms that wish to create more eco-friendly materials. Flax fibres actually have numerous qualities.
Johnny Beaugrand, Research Director. Biobased materials specialist- INRAE
They're very long and quite fine.
Alain Bourmaud, Research Engineer. Biobased materials specialist - Université de Bretagne Sud
The plant doesn't need watering.
Alessia Melelli, Post-doctoral Researcher in biobased materials - Synchrotron SOLEIL
And, it grows really quickly.
Johnny Beaugrand
The fibres are much lighter, less dense, compared to synthetic ones. Their mechanical performance is really incredible.
Alain Bourmaud
Along the lines of the fibreglass one.
Voice over
So, high performers, but to what extent? To assess the resistance of flax fibres, artificial ageing experiments can be carried out in the laboratory, but nothing can replace real conditions that are much more instructive. So, a team of scientists decided to study just how much really old flax (linen) textiles from different environments had deteriorated:
- a mummy in its sarcophagus,
- a tunic in an underground sanctuary
- as well as a fishing net exposed to seawater.
Alessia Melelli
We expect to have, for example, fibres in a tomb that have been in contact with a mummy's body, that have aged differently to the textiles discovered in a sanctuary, in contact with the ground.
Voice over
Biochemical changes in the linen were observed, first of all, using the Imaging part of Synchrotron SOLEIL's DISCO beamline. Today, it's a little sample of fibres taken from the strips used to stuff an Egyptian mummy from the Louvre Museum that's placed under an ultraviolet microscope. The other samples will follow.
Alessia Melelli
It's the linen that was found on the Pebos mummy and there are differences between these fibres here that are on the outside and these fibres here that are more so on the inside of the yarn.
Voice over
On the images, the cross-sections of each fibre, just around a dozen microns, appear clearly and seem to be in good condition. We can see the natural constituents of flax, such as lignin, in blue and green, and, around the edge of the yarn, proteins in red, from likely contamination of the mummy.
Frédéric Jamme, DISCO Beamline Manager - Synchrotron SOLEIL
The advantage of coming here, is that we can ensure them that their samples won't be destroyed, because this deep ultraviolet beam will naturally make their samples fluoresce. I can sort of light up or turn off specific molecules.
Alessia Melelli
Another thing that's really important for us, are the treatments that the fibres were subjected to. The Egyptians used resins or wax and, for us it's really important to see how the fibres have changed, how they've deteriorated upon contact with these types of materials.
Alain Bourmaud & Johnny Beaugrand
- It's beautiful!
- Yes, they're really beautiful. It's a wonderful observation area.
Voice over
To go further, to see if the structure of the fibres is well preserved, analyses are pursued on another Synchrotron SOLEIL instrument, the multiphoton microscope.
The cellulose chains, the main component of the fibres, can be seen on the screen.
Johnny Beaugrand
This is a polymer that can be really resistant in nature. It's organized in a crystalline fashion, it's interesting. All these resistant cellulose chains bathe in a sort of matrix that gives the fibre suppleness.
Alessia Melelli
Here, for example, it's really fine, but we can see it. This means that the cellulose is well organized. In this item here, it's well preserved.
Voice over
Another area of focus are the defects in the fibre known as kink-bands, which industrials seek to reduce.
Alain Bourmaud
We're really interested in fibre defects because they're like entry doors for micro-organisms, for humidity, sometimes areas where the fibre's cracked. The more defects the fibre has, the weaker its mechanical properties.
Voice over
The information collected for each sample will be used to model flax (linen) ageing in different types of environments (humid, warm, acid) and to provide industrials with valuable markers to anticipate fibre deterioration. They'll also help them identify resins to use or, on the contrary, to avoid when manufacturing new composite materials from flax. And a host of sectors are likely to be interested in these indicators.
Johnny Beaugrand
The automotive sector is a great example if we don't mention clothing, for example, there's a lot of flax fibres in hidden parts.
Alain Bourmaud
Aircraft seats made by some manufacturers contain a bit of flax.
Johnny Beaugrand
Mixed with plastics to make them lighter and to provide a bit more support.
Alain Bourmaud
The last winner of the Paris tennis tournament had a racket made from flax fibres. There's less vibration than with a carbon or fibreglass racket and the same goes for boats.
Voice over
And, although today, flax based materials only total a small share of the composite market, they seem to be heading for a great tomorrow in Europe.