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posted by janrinok on Wednesday October 26 2022, @08:37PM   Printer-friendly
from the fiber++ dept.

Arthur T Knackerbracket has processed the following story:

Single-use plastics have saved many lives by improving sanitation in health care. However, the sheer quantity of plastic waste—which can take from tens to hundreds of years to decompose—is a global pollution scourge. But now, in a study recently published in ACS Nano, researchers from The Institute of Scientific and Industrial Research (SANKEN) at Osaka University and collaborating partners have developed exceptionally versatile hydrogels and moldings that might replace conventional plastics.

The global scale of plastic waste urgently requires solutions and is being addressed from diverse perspectives. For example, in August 2022, National Geographic published a feature on recycling and repurposing plastic waste. Nevertheless, "the only long-term solution is to develop inexpensive, high-performance, plastic-like alternatives that don't persist in the environment," says Takaaki Kasuga, lead and senior author. "This is an active area of research, but the proposed alternatives to date haven't met society's needs."

Various techniques are currently available for molding nanofibers into a controlled orientation; i.e., to exhibit anisotropy. However, a simple technique that enables one to mold cellulose nanofibers from the nano- to macroscopic scale, on multiple spatial axes, has long been unavailable. To meet this need, Kasuga and coworkers used electrophoretic deposition to fabricate anisotropic cellulose-nanofiber-based hydrogels and moldings.

[...] There were several especially impressive outcomes of this study. One, cellulose nanofibers were oriented horizontally, randomly, and vertically by simply changing the applied voltage. Two, a multilayer hydrogel was easily prepared with alternating nanofiber orientations, in a manner that's reminiscent of biological tissue. Three, "we easily prepared complex architectures, such as microneedles and mouthpiece molds," says Kasuga. "The uniform nanofiber orientation helped suppress hydrogel cracking, and thus resulted in a smooth surface, upon drying."

The technique used in this study is not limited to cellulose nanofibers. For example, the researchers also used sodium alginate and nanoclay. Thus, multicomponent materials that exhibit controlled nanoscale orientations are also straightforward to prepare. An immediate application of this study is straightforward manufacturing of complex, hierarchical hydrogels and moldings over a wide range of spatial scales. Such ecofriendly hydrogels and moldings will be useful in health care, biotech, and other applications—and thus will help alleviate the need for petroleum-based plastics.

More information:
Takaaki Kasuga, Tsuguyuki Saito, Hirotaka Koga, et al. One-Pot Hierarchical Structuring of Nanocellulose by Electrophoretic Deposition, ACS Nano (2022). (DOI: 10.1021/acsnano.2c06392)


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  • (Score: 3, Funny) by krishnoid on Wednesday October 26 2022, @08:56PM (10 children)

    by krishnoid (1156) on Wednesday October 26 2022, @08:56PM (#1278628)

    To meet this need, Kasuga and coworkers used electrophoretic deposition to fabricate anisotropic cellulose-nanofiber-based hydrogels and moldings.

    Jargon being turned into real products, representatives producing more and more anachronistic metaphors [youtu.be] ... it's glorious.

    • (Score: 0) by Anonymous Coward on Wednesday October 26 2022, @10:23PM

      by Anonymous Coward on Wednesday October 26 2022, @10:23PM (#1278636)

      It's all about appealing to media and investors, and investors love syllables, and anything that sounds complex and important.
       

    • (Score: 4, Informative) by RamiK on Wednesday October 26 2022, @10:28PM (4 children)

      by RamiK (1813) on Wednesday October 26 2022, @10:28PM (#1278638)

      It just means they're electrocuting some pulp goo to orient the cells to such a uniform result that, once dry, the the solid is hard, smooth and clear like plastic.

      Anyhow, you could probably use the technique to coat fiberwood or something? Otherwise, the yields probably won't scale.

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      compiling...
      • (Score: 5, Interesting) by Immerman on Thursday October 27 2022, @01:35AM (3 children)

        by Immerman (3985) on Thursday October 27 2022, @01:35AM (#1278675)

        As I recall converting wood fiber to micro- or nano-cellulose is a relatively cheap mechanical process. Essentially a fine grind and water rinse to remove the lignin and other bonding agents, I think.

        There's a reason nano-cellulose is a popular food additive (it's a powerful food-safe gelling agent good for thickening sauces), and the lumber industry has been pushing hard to find additional real-world applications for the materials. It has the potential to convert mountains of near-worthless sawdust into a valuable cash stream. And the material properties really are pretty astounding - I seem to recall cast nanocellulose has a tensile strength comparable to aluminum.

        • (Score: 2) by RamiK on Thursday October 27 2022, @02:42AM (2 children)

          by RamiK (1813) on Thursday October 27 2022, @02:42AM (#1278687)

          I don't think cellulose nanofibers are cheap but I'm not a chemist so...

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          compiling...
          • (Score: 3, Informative) by Immerman on Thursday October 27 2022, @03:27PM (1 child)

            by Immerman (3985) on Thursday October 27 2022, @03:27PM (#1278755)

            A quick search suggests $1-2/kg in small packages, presumably much cheaper by the ton.

            • (Score: 3, Informative) by RamiK on Thursday October 27 2022, @06:24PM

              by RamiK (1813) on Thursday October 27 2022, @06:24PM (#1278808)

              I'm not a chemist so I was trying to avoid this topic since I know the raw is just cheap wood but:
              I was trying to avoid the topic since I'm not qualified to talk about it but processed CNF is quite expensive and it sounds like they processed theirs extensively: https://www.researchgate.net/figure/Production-Prices-of-Different-CNF-Grades-and-the-Cost-to-Obtain-a-75-Increase-in_tbl3_280234082 [researchgate.net]

              TEMPO-oxidized cellulose pulp (carboxyl content, 1.8 mmol/g) was supplied by DKS Co., Ltd. The TEMPO-oxidized cellulose pulp slurry was homogenized using a high-pressure water-jet system (Star Burst, HJP-25008, Sugino Machine Co., Ltd., Japan) equipped with a ball-collision chamber. The injected slurry was repeatedly passed through a small nozzle (⦶ 0.15 mm) under a pressure of 200 MPa. A 0.2 wt % CNF/water dispersion was obtained after the slurry was passed through this nozzle 50 times. The width of the CNFs was ∼3 nm, and the average length of the CNFs was 181 ± 77 nm. The length of the CNFs was determined using an atomic force microscope (AFM, Nanocute, SII Nano Technology Inc., Japan) in the dynamic force microscope (DFM) mode and by using ImageJ software. Laboratory-grade sodium alginate was purchased from Nacalai Tesque, Inc. (Japan) and dissolved in distilled water at a concentration of 0.2 wt %. The nanoclay (laponite)/water dispersion was kindly provided by Dr. Zhifang Sun, RIKEN (Japan). Laponite XLG (LPN, thickness ∼1 nm; lateral size ∼25 nm) was purchased from Rockwood Additives Ltd. (UK). LPN powder (4.5 g) was dispersed in water (50 mL) and vigorously stirred for 10 min at 25 °C to form a homogeneous slurry with a concentration of 9 wt %. The slurry was diluted to 0.4 wt % before use.

              But again, I'm not a chemist and I'm not qualified to determine how the costs in energy and materials and yields scale here so I really shouldn't say anything more.

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              compiling...
    • (Score: 2) by FatPhil on Wednesday October 26 2022, @10:30PM (3 children)

      by FatPhil (863) <{pc-soylent} {at} {asdf.fi}> on Wednesday October 26 2022, @10:30PM (#1278639) Homepage
      I think that translates to "we grew cotton". Because that's how I would create a cellulose-based fibre that would be useful for making an alternative to plastic bags, or what-have-you.
      --
      Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
      • (Score: 2) by Barenflimski on Wednesday October 26 2022, @10:57PM (2 children)

        by Barenflimski (6836) on Wednesday October 26 2022, @10:57PM (#1278648)

        So far I've got electrocuted cotton.

        • (Score: 2) by FatPhil on Thursday October 27 2022, @02:48PM

          by FatPhil (863) <{pc-soylent} {at} {asdf.fi}> on Thursday October 27 2022, @02:48PM (#1278737) Homepage
          You lucky puppy! My local kink store doesn't stock those :(
          --
          Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
        • (Score: 2) by krishnoid on Friday October 28 2022, @12:45AM

          by krishnoid (1156) on Friday October 28 2022, @12:45AM (#1278873)

          At least you weren't trying to open a bag [youtu.be] in a cotton factory when that happened.

  • (Score: 2) by c0lo on Thursday October 27 2022, @12:30AM (9 children)

    by c0lo (156) on Thursday October 27 2022, @12:30AM (#1278663) Journal

    have developed [a solution] that might replace some of the conventional plastics

    I mean, renewable as it may be, I don't think the plants can regenerate so fast to satiate the demand. Note that we already close to using wood and cellulose, for other purposes, in an unsustainable way - adding one more pressure on supply won't help.

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    https://www.youtube.com/watch?v=aoFiw2jMy-0
    • (Score: 5, Interesting) by Immerman on Thursday October 27 2022, @01:38AM (8 children)

      by Immerman (3985) on Thursday October 27 2022, @01:38AM (#1278676)

      They regenerate millions of times faster than than our petrochemical reserves...

      They're also potentially a lot more cost effectively to recycle, and can be composted instead of leaching toxic chemicals into the environment for centuries

      • (Score: 2) by Tokolosh on Thursday October 27 2022, @02:47AM (2 children)

        by Tokolosh (585) on Thursday October 27 2022, @02:47AM (#1278688)

        Plastics are "toxic chemicals" now? I don't think you the technical meaning of "toxic".

        Landfill plastic and be done with it. A properly designed and maintained landfill does not leach anything into the environment, toxic or not. Less environmental impact than recycling - prove me wrong.

        • (Score: 3, Informative) by Immerman on Thursday October 27 2022, @03:12PM (1 child)

          by Immerman (3985) on Thursday October 27 2022, @03:12PM (#1278748)

          Plastic breaks down into a wide range of pseudo-hormones which cause long term health problems. A chronic toxin rather than an acute one, but a problem nonetheless.

          Meanwhile we've been doing a piss-poor job of consistently getting plastic into the landfills (and keeping it there) so far. And despite our best efforts landfills tend to leach there toxins into the surrounding environment, especially oncethe plastic lineers start to break down.

          • (Score: 2) by Tokolosh on Friday October 28 2022, @04:06PM

            by Tokolosh (585) on Friday October 28 2022, @04:06PM (#1279015)

            Please provide an example of harm caused by plastics in a landfill.

      • (Score: 2) by c0lo on Thursday October 27 2022, @03:27AM (4 children)

        by c0lo (156) on Thursday October 27 2022, @03:27AM (#1278692) Journal

        They regenerate millions of times faster than than our petrochemical reserves

        It still doesn't automatically make the use of them sustainable.

        (I wasn't making the point of "don't use them and continue to use plastic", but just "be careful how you use them, they may not be enough if you try to replace all the conventional plastic". Not like there aren't alternative solutions)

        --
        https://www.youtube.com/watch?v=aoFiw2jMy-0
        • (Score: 2) by Immerman on Thursday October 27 2022, @03:22PM (3 children)

          by Immerman (3985) on Thursday October 27 2022, @03:22PM (#1278752)

          True, cost-effectively recyclable materials are much preferable - but so far they've all also been more expensive and less convenient. Do you want to buy meat pre-packaged in opaque foil rather than clear plastic, so you can't see it's condition? I'm not sure we're going to realistically get back to the butcher cutting and wrapping your meat on request - not for the mass market. And of course paper is made from exactly the same stuff and these new materials.

          However, micro- and nano-cellulose should actually be highly recyclable, just as their macro-cellulose cousin paper is. And nothing says we have to make it from slow growing trees - that's just a result of the lumber industry being the ones to push it as they try to turn their waste stream into a profit source. Practically every plant is composed of mostly cellulose, and fast growing plants like hemp have long been recognized as a superior alternative to wood fiber in virtually every application other than actual lumber - which is why the lumber industry helped back the demonizing of cannabis in the first place.

          • (Score: 2) by c0lo on Thursday October 27 2022, @03:53PM (2 children)

            by c0lo (156) on Thursday October 27 2022, @03:53PM (#1278767) Journal

            but so far they've all also been more expensive

            Not when you factor in the externalities.

            Do you want to buy meat pre-packaged in opaque foil rather than clear plastic, so you can't see it's condition? I'm not sure we're going to realistically get back to the butcher cutting and wrapping your meat on request - not for the mass market.

            Honestly, I'm buying my meat from the local butcher, and I get it wrapped in waxed paper. True, I drive 12 km for it and back, but I do it 2/w together with the other shopping; it was me that moved into an area that far from the closest commercial zone - I can't keep a horse around tho - so probably my choice damages the environment more that some plastic foil.

            And nothing says we have to make it from slow growing trees - that's just a result of the lumber industry being the ones to push it as they try to turn their waste stream into a profit source.

            It would be good if that was what they were doing, but it seems it's far less costly to them to waste some more [soylentnews.org] than to collect their waste. Wrong incentives from the part of the society.

            and fast growing plants like hemp have long been recognized as a superior alternative to wood fiber

            I wonder what happens with the wheat straws? The farmers certainly collect and bale them, but they aren't that good as fodder, are they?

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            https://www.youtube.com/watch?v=aoFiw2jMy-0
            • (Score: 2) by Immerman on Thursday October 27 2022, @05:05PM

              by Immerman (3985) on Thursday October 27 2022, @05:05PM (#1278785)

              >Not when you factor in the externalities.

              Sure. But externalities are, sadly, mostly irrelevant within a market economy - hence the name, they are external to the market. They can only be addressed with other externalities - be they taxes, bans, or enough customers banding together to boycott products that manufacturers change strategies (hey, it can theoretically happen)

              I believe straw is still decent fodder - the whole point of ruminants having multiple stomachs is to ferment cellulose into more digestible molecules. And cellulose is the main ingredient in pretty much every part of the plant (maybe not of fruit and nuts?).

              But yeah. Straw, algae, dead leaves... they don't have the long, strong fibers of hemp, but for nanocellulose you're breaking those long fibers down nearly into individual polymer units, so I don't think it matters.

            • (Score: 2) by Tokolosh on Friday October 28 2022, @04:18PM

              by Tokolosh (585) on Friday October 28 2022, @04:18PM (#1279019)

              What is the carbon footprint of the waxed paper compared to plastic film? Where does the wax come from? What are the environmental consequences of your move 12 km from civilization?

              What is the environmental cost of a methane-emitting horse, which takes up space, consumes resources and produces effluent even when not in use? Does it have less environmental impact than a gas-powered car, relative to its utility?

              Correcting for externalities is a noble endeavor. Sadly, it is mostly done by emotion and not science and economics.

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