Name: I Can't Believe It's Not Wood
Uploaded: 2020-03-30T03:41:45.000Z
Duration: 5 min 25 s
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You can probably spot fake wood a mile away.

And you might wonder why we even bother trying.

wanting to make fake wood -- and some good reasons

One reason we want fake wood is saving our forests.

that looks like wood and has its properties,

we don't have to keep cutting down actual trees.

Plus, wood has an incredibly complex architecture

-- and this has actually inspired materials scientists

the knots -- nothing else really has that.

You'll see this sort of scaffolding that looks like a bunch of tubes squished together.

These tubes are actually the tree's cells, meant to channel water throughout the plant.

Those cells' walls are, in turn, made of cellulose fibers embedded in a blob of hemicellulose

and lignin -- all chemicals that contribute to a fibrous, rigid structure.

And those cellulose fibers aren't just tossed willy nilly into the tree, either.

They're oriented to match the direction of the tree or branch they're on.

This means that the tree's properties are anisotropic: they're different in different

For example, thanks to those aligned bundles of cellulose fibers, trees are stronger across

If you try to chop a tree horizontally, lumberjack-style, these super-strong cellulose fibers will bear

the brunt of the force and make it hard to chop.

But if you try to cut wood vertically, you'll be hitting the not-as-strong lignin-hemicellulose

matrix -- which happens to be much easier to break.

This complexity explains other things, too.

Like why some woods can be 1000 times stiffer than others, since their microstructures and

even their exact compositions can be vastly different.

This complexity also means that wood, and all its awesome properties, are super hard

There has been at least one attempt in the scientific literature.

A 2018 paper published in Science Advances described a way of making artificial wood

using special water-soluble polymers frozen in liquid nitrogen and alcohol to create a

Then they removed the solvents to lock-in that configuration, and heated the whole thing

The authors found that by varying the cooling rate, they could fine-tune the properties

And some of those had similar properties to real wood, like how much they could be compressed.

They even looked similar to real wood, with some advantages like being more resistant

But it's important to note that this was done entirely inside a lab with a homemade

This probably won't translate easily to a much larger scale, so you will likely not

see these artificial woods in stores anytime soon.

There are other methods scientists could use to make wood-like structures, but they have

As a result, many commercial attempts at making artificial wood only focus on replicating

And that inability to mimic all the properties of wood rather than just one or two means

that fake wood won't fool us -- for now, at least.

Many wood substitutes, for example, are made by mixing actual wood byproducts like wood

flour with some sort of plastic or adhesive.

That's basically really fine sawdust, not a gluten-free cupcake ingredient.

You've probably seen these wood-plastic composites in decks or lining your door.

Since these composites are made of, well, wood and plastic, they very often have properties

that lie in between those of their constituent materials.

So they are usually less stiff than solid wood but more rigid than plastic -- in general,

And plastic here actually gives the material another advantage: it won't absorb as much

moisture, so it's less vulnerable to rot.

But what about products that don't have any wood at all?

One material that's gained traction as a wood alternative is something that's used

Cellular PVC is made by blowing bubbles through melted plastic and other additives to form

a solid material with little bubble-like holes throughout it, giving it more structure at

But while that makes cellular PVC more lightweight, it just isn't like wood.

And even if it's more durable than wood, this plastic substitute certainly doesn't

Unless, of course, you do a fancy paint job -- which can help with the looks, but that's

So even if wood's been around a while, we're still working on ways to improve on nature's

And maybe in the future, that'll not only help us save the trees but also synthesize

a whole range of materials we've never even dreamed of.

Outro: Imitating the structure of materials like

wood requires understanding space, shapes, and angles -- the kind of thing you learn

And if that's piqued your interest, Brilliant offers a brand new course on Geometry Fundamentals