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Hardened wood as a renewable alternative to steel and plastic

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21–30 of 282 posts

Re: Hardened wood as a renewable alternative to steel and plastic

#23
post #2

Can't read the article. How energy efficient and environmentally friendly is the hardening process compared to making steel? And is it a "in 20 years" thing again, like all new battery tech?

Not sure if this is exactly the same but cross laminated timber (CLT) is already being used for constructing all kinds of buildings. Executive summary of its qualities: - Stronger and lighter than concrete. Think thinner floors and walls but with similar strength and load-bearing capability; less tonnes of material to move around. That alone is a big advantage. - Several buildings across the world already exist; more…

A blocker to deployment would be getting building codes updated to permit use. From memory, wood was only approved for 3 story or less structures in most of the US. And building codes tend to be updated extremely slowly and conservatively.

Re: Hardened wood as a renewable alternative to steel and plastic

#24
post #12

I've been intrigued for a while about various modified wood technologies (eg hardened wood, transparent wood), but I'm always disappointed because it usually ends up just being a minor support structure for a very non-wood material (generally epoxy). This one shows a compression step, so maybe it's different, but I'd really like more info on whether this is actually renewable or sustainable in any interesting sense.…

Curious about your opinion on bamboo products. I assume you're referring to modern bamboo desks, shelves, and other items that are made from Chinese bamboo and made in China. They typically slice the bamboo grass pieces into ~8 sections, then use planing machines to create planks※. These are then pressed and glued together to make products. These products are then shipped overseas using the same methods as other products.

If the glue used is either sustainable or they don't use very much of it, and the bamboo is grown locally, what makes it less sustainable than using wood? And certainly more less energy-intensive than steel.

※ I am not a woodworker, don't know terminology.

Re: Hardened wood as a renewable alternative to steel and plastic

#25
Here is a non-paywalled description of the process. https://www.popularmechanics.com/science/environment/a167588...

>Lignin is what makes wood rigid and brown. Somewhat counterintuitively, Hu and his team removed the wood's lignin polymers in order to make their wood even stronger.

>The lingin removal allowed the team to compress the wood under a mild heat of around 150 degrees Fahrenheit. Without the lignin binding together the wood's cells, the scientists were able to make its cellulose fibers very tightly packed.

>When the fibers are jammed together...the wood's fibers begin to form hydrogen bonds.

So essentially they found a different (more natural-sounding for sure) way to polymerize cellulose. Right now bamboo or sugar cane are broken down and polymerized all the time via a different process to make plant-based plastics, rayon, etc.

Re: Hardened wood as a renewable alternative to steel and plastic

#26
post #16

I’ve seen this before. It starts getting curious at the “chemical treatment” step.

They're taking the lignite out of the cellulose, and then compressing the resulting soft mesh into a harder material. A few years ago, "transparent wood" was a thing. That was taking out the lignite, and putting some transparent plastic in.

Not clear what's special about their compression step.

Re: Hardened wood as a renewable alternative to steel and plastic

#27
post #2

Can't read the article. How energy efficient and environmentally friendly is the hardening process compared to making steel? And is it a "in 20 years" thing again, like all new battery tech?

Not sure if this is exactly the same but cross laminated timber (CLT) is already being used for constructing all kinds of buildings. Executive summary of its qualities: - Stronger and lighter than concrete. Think thinner floors and walls but with similar strength and load-bearing capability; less tonnes of material to move around. That alone is a big advantage. - Several buildings across the world already exist; more…

Looks like giant plywood. I'm actually really curious how it handles moisture content changes. Does it crack and is it dimensionally as stable as plywood?

Re: Hardened wood as a renewable alternative to steel and plastic

#29
As far as I know, the Earth's surface cannot meet humanity's current need for hydrocarbons, polymers or building materials. Biomass production is limited by sun energy and most importantly phosphorus and nitrogen cycles. Even hundred of years ago, people were already exhausting regenerative capacities and back then there were only around half a billion humans living on all this planet. Petrol chemistry and mineral exploitation saved Earth's ecosphere short term. But obviously that can't last forever.

It's nice to have functional carbon sinks and all, but we will never replace even the majority of petrol, metallic and mineral based production of today with biomass derived alternatives. The surface and geological cycles cannot support that. And food is priority. If phosphorus rock is gone, we're fucked for good.

We need to cut down.

Re: Hardened wood as a renewable alternative to steel and plastic

#30

As far as I know, the Earth's surface cannot meet humanity's current need for hydrocarbons, polymers or building materials. Biomass production is limited by sun energy and most importantly phosphorus and nitrogen cycles. Even hundred of years ago, people were already exhausting regenerative capacities and back then there were only around half a billion humans living on all this planet. Petrol chemistry and mineral ex…

We need to mine in space.
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