Materials

Bioplastic made from wood powder entirely degrades in three months

Bioplastic made from wood powd...
Scientists have used waste products from a lumber mill to produce an environmentally friendly bioplastic
Scientists have used waste products from a lumber mill to produce an environmentally friendly bioplastic
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Scientists have used waste products from a lumber mill to produce an environmentally friendly bioplastic
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Scientists have used waste products from a lumber mill to produce an environmentally friendly bioplastic

Motivated by our growing problem with plastics, which are environmentally damaging both to produce and after they're disposed of, scientists are tinkering away with more eco-friendly forms of the material. Researchers at Yale University have put forward a candidate that ticks a number of important boxes, developing a new bioplastic with high strength but an ability to degrade entirely in the space of three months.

The pursuit of more environmentally friendly bioplastics has seen scientists turn to all sorts of biomass as their starting point. These possibilities include egg shells, plants and even tequila waste, and all invariably raise the prospect of a material that is not only greener to produce, but doesn't take centuries to break down like conventional petroleum-based plastics do.

The team at Yale began with a wood powder that is a typical waste product at lumber mills, and used a biodegradable solvent to reduce it to a slurry of organic polymers and cellulose with hydrogen bonding and entanglement at a nanoscale level. This slurry was then able to be cast as a bioplastic, which the team put to the test against conventional plastics.

The experiments involved burying sheets of the bioplastic in soil, where they became fractured after two weeks and degraded completely in three months. The bioplastic also exhibited high mechanical strength, stability when made to hold liquids, and resistance to UV light.

“There are many people who have tried to develop these kinds of polymers in plastic, but the mechanical strands are not good enough to replace the plastics we currently use, which are made mostly from fossil fuels,” says co-author Yuan Yao. “We’ve developed a straightforward and simple manufacturing process that generates biomass-based plastics from wood, but also plastic that delivers good mechanical properties as well.”

In addition to degrading at a rapid rate, the bioplastic can also be returned to its original slurry form, which allows the solvent to be recovered and reused.

“That, to me, is what really makes this plastic good: It can all be recycled or biodegraded,” says Yao. “We’ve minimized all of the materials and the waste going into nature.”

The team imagines a number of uses for this new bioplastic, such as molding it into a film for bags and packaging, or even into products for use in construction and automotive manufacturing.

The research was published in the journal Nature Sustainability.

Source: Yale University

17 comments
17 comments
Worzel
The BIG question is, what triggers the biodegrade function?
Do you go to the product store, and find a pile of biodegraded sawdust?
Sawmills produce large amounts of sawdust, which they often just burn, but the cost of collecting it, and transporting it to a factory would probably outweigh its value. Therefore the next step would be to use wood directly from the forests, which are presently being decimated at an unprecedented rate, both by human predation, diseases, and forest fires.
Anything which increases this destruction, cannot be good, in spite of its ''Green'' intentions.
Virtually al the present plastics being discarded irresponsibly, are recyclable, so its not the actual product, but bad behaviour by humans that is the problem, and which needs to be corrected.
Alien
The biodegrading sounds excellent...so long as it doesn't happen in use. Could we be told about the duty life of items made with this plastic. For example a plastic garden chair: how long would it last in normal use?
piperTom
Like @Worzel, I'm curious about what triggers the biodegrade. I'd like to drink my soda before the bottle starts to rot. But unlike @Worzel, I'm not alarmed about loss of forest area. For several decades, the reforestation of North America has kept pace with the demand for wood products (not counting pandemic effects). As to the rest of the world, the deforestation has been declining there, too. For reference see https://www.humanprogress.org/what-do-the-numbers-show-about-global-deforestation/
guzmanchinky
That is really cool, but what if you want your water bottles to last a long time (say as an emergency supply)?
Kevin Ritchey
My father helped build and maintain paper mills for a variety of companies in several countries and pretty much learned everything while only graduating from the 8th grade. The rest came from correspondence courses and pure on-the-job learning essentially earning the equivalent of a doctorate in chemical engineering. Given the opportunity after 46-years in the business, he could have come up with something similar if asked. It sounds like a cellophane derivative to me but I wouldn’t know since my knowledge base was in psychology. Never got to practice because of spinal cancer complications but life is like that. He was successful and I was not. Let’s see if they can make something of their “discovery” that actually gets applied in and benefits the real world.
Non-Compos_Mentis
Re comment by Worzel: "... the next step would be to use wood directly from the forests, which are presently being decimated at an unprecedented rate ...."
__ Pulpwood is grown as a farm crop. I have a farm which is all in Loblolly Pine, which is used for cardboard boxes, paper bags. etc.
Robt
Re Worzel,
According to NASA and accompanying satellite photos, the world is approximately ten percent greener now than it was twenty years ago.
Yes, there are some very severe issues in the Amazon basin, and also elsewhere, but overall the world’s forests are not, “being decimated at an unprecedented rate”.
JustSaying
Yay! Paper bags at the grocery store again!
CAVUMark
Plastic should be banned soon. I suggest a Manhattan project to create plastics replacement. Now that we have a COVID vaccine why not put that brain power on a new project.
toni24
The idea of plastic grocery bags and bags for other consumer products thta will bio-degrade in land fills and eliminate that source of micro plastics is great. But how long would a plasti hulled kayak or boat last in sea water, or as others have asked, the durability of water and soft drink bottles. How long would those things last?
I personally like the technology where they collapse the cellular walls of wood fibers and compress the plywood to a fraction of its original volume and makes it a :plastic: moldable product. Being made of wood fibers and held together by the lignin of wood, it would be a bio friendly product that should last like wood and break down like wood by the same b acteria ad fungus that decays wood