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Flame-retardant coating for wood is made from ... wood

Flame-retardant coating for wo...
HefCel-coated wood (left) and untreated wood, after a 30-second flame test
HefCel-coated wood (left) and untreated wood, after a 30-second flame test
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HefCel-coated wood (left) and untreated wood, after a 30-second flame test
HefCel-coated wood (left) and untreated wood, after a 30-second flame test

Wood is an established and versatile construction material, used to build everything from high-rises and airports to apartment buildings. It also, however, is not immune to catching fire. A new coating could help keep that from happening, and it's actually made from wood.

Developed by scientists at the VTT Technical Research Centre of Finland, the solution incorporates nanocellulose – this material in turn consists of microscopic cellulose fibers obtained from wood pulp.

Manufactured utilizing a patented technology known as HefCel (High-Consistency Enzymatic Fibrillation of Cellulose) the gel-like nanocellulose reportedly has 10 times the solids content of similar materials. As a result, when applied to wood – which nanocellulose naturally adheres to – it's very good at forming an airtight barrier that keeps oxygen from reaching that wood's surface. This means that the wood is significantly less likely to combust when exposed to a flame.

It is thought that the coating could be particularly useful when mixed with a pigment, then applied to wood in the form of a sprayed- or brushed-on paint or stain.

Initial batches of the HefCel-based coating have reportedly performed well in lab tests, and an energy-efficient production process has been developed. The scientists are now working on scaling up that process, making it simpler yet at the same time even more efficient. They're also currently looking for an industry partner to help commercialize the technology.

Source: VTT

Wood doesn't really burn. It's the volatiles from heated wood that burn, and the changes in shape from driving those volatiles out of the wood's molecular structure. So yeah, it makes sense that protecting the surface would be a good fire-retardant step.
amazed W1
In the UK there is currently a built in fear of anything "combustible" being used in building fabric. This is mainly due to the media and political extravaganza after the Grenfell Tower disaster. So assuming components treated with the product pass the test required by Building Regulations, we may unfortunately not be able to get the benefits for some time.