People await the start of a product launch event at Apple’s new campus in Cupertino, California, US September 12, 2017. REUTERS/Stephen Lam
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Aug 1 (Reuters) – Apple Inc is dropping its mask mandate for corporate employees at most locations, the Verge reported on Monday, citing an internal memo. (https://bit.ly/3oJ3EQN)
This comes even as COVID-19 infections in the United States have been on the rise with the BA.4 and BA.5 subvariants of the Omicron variant accounting for more than 90% of infections, according to the US Centers for Disease Control and Prevention .
These subvariants have significant mutations from the earliest versions of Omicron and protection from vaccines wanes over time.
“Don’t hesitate to continue wearing a face mask if you feel more comfortable doing so,” the report quoted Apple as saying in the internal email. “Also, please respect every individual’s decision to wear a mask or not.”
Apple did not immediately respond to Reuters’ request for comment outside regular business hours.
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Reporting by Kanjyik Ghosh in Bengaluru; Editing by Subhranshu Sahu
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Video game spending in 2022 has continued to decline. According to a report from the NPD Group, spending has dropped 13% in the second quarter of 2022, as compared to the same period of time last year.
Total consumer spending on video gaming in Q2 amounted to $12.35 billion, a drop of $1.71 billion as compared to Q2 2021. Non-mobile subscription spending did increase in this period, but it was the only broad spending category to increase. In fact, decreased mobile spending accounts for much of the decline, according to the report. Spending on mobile games decreased by 12%. In other categories, hardware spending decreased by 1% and accessory spending by 11%.
Most of the most popular games in this period are mobile and multiplayer staples including Among Us, Diablo Immortal, Call of Duty: Warzone, Candy Crush Saga, GTA V, Minecraft, Mario Kart 8, and Pokémon Go. Elden Ring, LEGO Star Wars: The Skywalker Saga, Kirby and the Forgotten Land, as well as The Sims 4 were all also massive titles this quarter. In terms of hardware sales, Nintendo Switch took the crown, while PlayStation 5 generated the highest dollar sales.
The report attributes the decline to a broader return to work and other public places as well as an uncertain economic environment. Increased gas prices and general inflation have made budgets tighter. There’s also less widespread obstacles of fewer new releases and ongoing hardware shortages. However, even with all these factors, spending is still above pre-pandemic levels.
The pandemic broke video game spending records and kicked off a massive period of growth for the industry. Just this year however, spending began to decline. Q1 2022 saw a similar decline and May 2022 was the industry’s worst spending month since February 2020. As the report says, the overall state of the economy will have a large impact on future months.
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Apple Watch Series 7 is down to its lowest-ever price on Amazon. Photo: Apple
Amazon has an irresistible deal on the Apple Watch Series 7 that you should not miss. The 41mm Apple Watch Series 7 is down to $279.99 from $399—down to its lowest-ever price.
This is the same price the smartwatch was available for during Prime Day in July.
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Apple Watch Series 7 is the perfect smartwatch for your iPhone
Apple Watch Series 7 features a 20% bigger and brighter Retina Display than previous models. The front casing is also more durable and crack-resistant. Apart from an internal spec bump, the main highlight of the Apple Watch Series 7 is its faster charging speeds.
With the new charging puck that Apple bundles with the watch, you can top its battery from 0-80% in just 45 minutes. That means the watch will spend more time on your wrist and less on the charger.
With Apple Watch Series 8 not expected to bring any significant improvements, now would be a good time to pick up the current-gen model at its heavily discounted price.
Apple Watch Series 7 gets a massive $119 discount
Amazon is currently taking a whopping $119 off the Apple Watch Series 7. However, the deal is only available on the 41mm Green Aluminum Case model with Clover Sport band. Other 41mm Apple Watch variants are discounted by $69.01, bringing their price down to $329.99.
If you want the bigger 45mm Apple Watch, that’s on discount as well. The GPS-only configuration is available with a $39.01 discount, with an additional $30 off automatically applied at checkout. This translates into a total savings of $69.01.
You can also save an additional 20% on the Beats Studio Buds or Beats Fit Pro if you pair them with your Apple Watch Series 7 purchase. You need to have both items in the cart together while checking out to be eligible for the deal.
As the Apple Watch Series 8 launch draws closer, we should continue to see such deals on Series 7 for now.
TEM images for the particle sizes of red, green, cyan, and blue QDs used for the device fabrication and charge transport simulation. dQD is the average diameter of the QD nanoparticles. Insets are the snapshots of EL-driven monochromatic red, green, cyan, and blue QD-LED devices fabricated by the transfer printing technique. The size of the manufactured device is 3.0×1.5 mmtwo. Credit: Nature Communications (2022). DOI: 10.1038/s41467-022-31853-9
Researchers have designed smart, color-controllable white light devices from quantum dots—tiny semiconductors just a few billionths of a meter in size—which are more efficient and have better color saturation than standard LEDs, and can dynamically reproduce daylight conditions in a single light .
The researchers, from the University of Cambridge, designed the next-generation smart lighting system using a combination of nanotechnology, color science, advanced computational methods, electronics and a unique fabrication process.
The team found that by using more than the three primary lighting colors used in typical LEDs, they were able to reproduce daylight more accurately. Early tests of the new design showed excellent color rendering, a wider operating range than current smart lighting technology, and wider spectrum of white light customization. The results are reported in the journal Nature Communications.
As the availability and characteristics of ambient light are connected with well-being, the widespread availability of smart lighting systems can have a positive effect on human health since these systems can respond to individual mood. Smart lighting can also respond to circadian rhythms, which regulate the daily sleep-wake cycle, so that light is reddish-white in the morning and evening, and bluish-white during the day.
When a room has sufficient natural or artificial light, good glare control, and views of the outdoors, it is said to have good levels of visual comfort. In indoor environments under artificial light, visual comfort depends on how accurately colors are rendered. Since the color of objects is determined by illumination, smart white lighting needs to be able to accurately express the color of surrounding objects. Current technology achieves this by using three different colors of light simultaneously.
Quantum dots have been studied and developed as light sources since the 1990s, due to their high color tunability and color purity. Due to their unique optoelectronic properties, they show excellent color performance in both wide color controllability and high color rendering capability.
The Cambridge researchers developed an architecture for quantum-dot light-emitting diodes (QD-LED) based next-generation smart white lighting. They combined system-level color optimization, device-level optoelectronic simulation, and material-level parameter extraction.
The researchers produced a computational design framework from a color optimization algorithm used for neural networks in machine learning, together with a new method for charge transport and light emission modeling.
The QD-LED system uses multiple primary colors—beyond the commonly used red, green and blue—to more accurately mimic white light. By choosing quantum dots of a specific size—between three and 30 nanometers in diameter—the researchers were able to overcome some of the practical limitations of LEDs and achieve the emission wavelengths they needed to test their predictions.
The team then validated their design by creating a new device architecture of QD-LED based white lighting. The test showed excellent color rendering, a wider operating range than current technology, and a wide spectrum of white light shade customization.
The Cambridge-developed QD-LED system showed a correlated color temperature (CCT) range from 2243K (reddish) to 9207K (bright midday sun), compared with current LED-based smart lights which have a CCT between 2200K and 6500K. The color rendering index (CRI)—a measure of colors illuminated by the light in comparison to daylight (CRI=100)—of the QD-LED system was 97, compared to current smart bulb ranges, which are between 80 and 91.
The design could pave the way to more efficient, more accurate smart lighting. In an LED smart bulb, the three LEDs must be controlled individually to achieve a given color. In the QD-LED system, all the quantum dots are driven by a single common control voltage to achieve the full color temperature range.
“This is a world-first: a fully optimized, high-performance quantum-dot-based smart white lighting system,” said Professor Jong Min Kim from Cambridge’s Department of Engineering, who co-led the research. “This is the first milestone toward the full exploitation of quantum-dot-based smart white lighting for daily applications.”
“The ability to better reproduce daylight through its varying color spectrum dynamically in a single light is what we aimed for,” said Professor Gehan Amaratunga, who co-led the research. “We achieved it in a new way through using quantum dots. This research opens the way for a wide variety of new human responsive lighting environments.”
The structure of the QD-LED white lighting developed by the Cambridge team is scalable to large area lighting surfaces, as it is made with a printing process and its control and drive is similar to that in a display. With standard point source LEDs requiring individual control this is a more complex task.
Optoelectronic devices that emit warm and cool white light
More information:
Optoelectronic System and Device Integration for Quantum-Dot Light-Emitting Diode White Lighting with Computational Design Framework, Nature Communications (2022). DOI: 10.1038/s41467-022-31853-9
Provided by University of Cambridge
citation: Smart lighting system based on quantum dots more accurately reproduces daylight (2022, August 3) retrieved 3 August 2022 from https://phys.org/news/2022-08-smart-based-quantum-dots-accurately.html
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Who among us isn’t depressingly familiar with the constant tug of war between putting off tasks that require focus, and, like a moth to a flame, being drawn to distraction?
Sometimes we blame ourselves, cursing our tendency to procrastinate. But we should give ourselves a break. We’re living in an unprecedented age where billions of dollars have been made by machines designed to tempt us away from doing what we had planned to do.
These thoughts are hardly new. But something happened recently, which—ironically—has captured no small amount of attention and provided me with a glimmer of hope that the Internet that has rewired our minds could also be used to untangle them.
Last month, YouTube suddenly suspended Lofi Girl, a music livestream that had been broadcasting, uninterrupted, for some 20,843 hours—more than two years—gathering 660 million views in the process. The takedown was due to a false copyright claim and was later reversed. But such is Lofi Girl’s popularity that its fans were, briefly, bereft.
why? Ella’s Lofi Girl is a nonstop playlist of “lofi beats,” set to a video animation of a student working at her desk. Lofi (low fidelity) beats are soft hip-hop rhythms with no vocals, optimized to engender calm and focus. The images of the student, made by Colombian artist Juan Pablo Machado, are also vital to the channel’s purpose. As day passes into night, the cityscape changes, a cat wags its tail, and Lofi Girl keeps writing as the beat goes on.
For Emma Winston, an ethnomusicologist at the University of London who has studied Lofi Girl, its appeal is that it’s “cozy and calming and often designed to sound analogue and aged, like it’s from a past era that may or may not have actually existed. ” Central to the channel’s function, she says, is a chat window alongside the video where users leave positive “you-got-this” comments for one another, which is rare on sites like YouTube. “That can offer a sense of companionship, but it’s one that’s very low pressure—you can enjoy the music completely alone, nobody needs to know you’re there, but you can still feel co-present with others in a space.”
Winston has observed that while many types of music thrive on the Internet, lofi beats is, uniquely, a genre created because of the Internet to answer the cravings of those who, like me, aren’t seeking silence but peace. “There’s very little going on in the sonic range we associate with excitement,” says Reed Arvin, a record producer based in Nashville. “We call that range ‘bright.’ Lofi Girl’s music isn’t just musically mellow, it’s sonically mellow.”
Also mellow is the way Lofi Girl rejects some of the core mechanisms underpinning the business models of Big Tech. Its continuous playback deprives YouTube of any moments in which to serve up new content and ads designed to send users down the so-called rabbit hole. Winston likens the stream to “a still point” in the storm of content that demands our attention from all sides.
Lofi Girl also provides a more satisfactory answer to suggestions that we should simply ignore digital distractions. Tyler Lok, a fan from Salt Lake City, says the effect of the Internet on our minds is that interruptions can only be turned “off” if something else is “on.”
“We occupy ourselves with stimulation constantly… to the point that our brains begin to lose the ability to be bored,” says Lok. “Streams [like Lofi Girl] allow us to stay plugged into digital stimulation and still get some work done.”
I can’t stop playing with Midjourney. It may signal the end of human creativity or the start of an exciting new era, but here’s me, like a monkey at a typewriter chucking random words into the algorithm for an instant hit of this-shouldn’t-be-as-good- as-it-is art.
For those who don’t know, Midjourney is one of a number of image-generating AI algorithms that can turn written prompts into unworldly pictures, It, along with OpenAI’s DALL-E 2, have been having something of a moment in the last month as people get their hands on them and try to push them to their limits. Craiyon – formerly DALL-E mini – is an older, less refined and very much wobblier platform to try too. It’s worth having a go just to get a feel for what these algorithms can and can’t do – though be warned, the dopamine hit of seeing some silly words turn into something strange, beautiful, terrifying or cool within seconds is quite addictive. A confused dragon playing chess. A happy apple. A rat transcends and perceives the oneness of the universe, pulsing with life. Yes Sir, I can boogie.
Within the LBB editorial team, we’ve been having lots of discussions about the implications of these art-generating algorithms. What are the legal and IP ramifications for those artists whose works are mined and drawn into the data set (on my Midjourney server, Klimt and HR Giger seem to be the most popular artists to replicate but what of more contemporary artists?). Will the industry use this to find unexpected new looks that go beyond the human creative habits and rules – or will we see content pulled directly from the algorithm? How long will it take for the algorithms to iron out the wonky weirdness that can sometimes take the human face way beyond the uncanny valley to a nightmarish, distorted abyss? What are the keys to writing prompts when you are after something very specific? Why does the algorithm seem to struggle when two different objects are requested in the same image?
Unlike other technologies that have shaken up the advertising industry, these image-generating algorithms are relatively accessible and easy to use (DALL-E 2’s waitlist aside). The results are almost instant – and the possibilities, for now, seem limitless. We’ve already seen a couple of brands have a go with campaigns that are definitely playing on the novelty and PR-angle of this new technology – and also a few really intriguing art projects too…
Heinz – ‘AI Ketchup’
Agency: Rethink
The highest profile commercial campaign of the bunch is Rethink’s new Heinz campaign. It’s a follow up to a previous campaign, in which humans were asked to draw a bottle of ketchup and ended up all drawing a bottle of Heinz. This time around, the team asked Dall-E 2 – and the algorithm, like its human predecessors, couldn’t help but create images that looked like Heinz branded bottles (albeit with a funky AI spin). In this case, the AI is used to reinforce and revisit the original idea – but how long will it take before we’re using AIs to generate ideas for boards or pitch images?
10 Iconic Brands
Agency: 10 Days
Creative agency 10 Days decided to get experimental with a project that was all about letting their team get their heads around the possibilities and limitations of the technology. They used Midjourney to create ads for ten iconic brands – and for each brand they created 24 images. As well as being a very timely PR opportunity for the agency, it was a chance to test, produce and consider. Florence Burge spoke to LBB here.
Short Film – ’31 Days’
Animation: Jeremy Higgins
This artsy animated short by art director and designer Jeremy Higgins is a delight and shows how a sequence of similar AI-generated images can serve as frames in a film. The flickering effect ironically gives the animation a very hand-made stop motion style, reminding me of films that use individual oil paintings as frames. It’s a really vivid encapsulation of what it feels like to be sucked into a Midjourney rabbit hole too… I also have to tip my hat to Stefan Sagmeister who shared this film on his Instagram account.
Cosmopolitan – ‘The AI Issue’
For the latest issue of Cosmopolitan, creative Karen X Cheng used Dall-E 2 to create a dramatic and imposing cover – using the prompt: ‘a strong female president astronaut warrior walking on the planet Mars, digital art synthwave’. There’s a deep dive into the creative process that also examines some of the potential ramifications of the technology on the Cosmopolitan website that’s well worth a read.
Video Game – ‘Daydreams’
Studio: T&DA
Why stick to one viral trend when you can combine two? Sydney-based studio T&DA has created a Wordl-inspired game called ‘Daydreams’ in which players are served up with a Midjourney-generated image and challenged to guess the writing prompts. This reverse engineering process might well prove to be handy for copywriters trying to figure out how to write for the algorithms. You can access an invite to the Discord server here.
BT Sport – ‘Believe It’
Here’s a cheeky sixth entry to High Five. This execution is part of a wider summer platform for BT Sport, centered around belief – in this case football pundit Robbie Savage is served up a Dall-E 2 image of striker Aleksander Mitrović lifting the golden boot. Fulham have just been promoted to the Premier League – but though Robbie can see it, he can’t quite believe it.
Another Houston Outlaws rebuild may be on its way as the organization has been actively offering three players, including 2021 Overwatch League Rookie of the Year Se-Hyun ‘Pelican’ Oh, to other teams, multiple sources have told Dexerto.
Sources said that the Outlaws management has held talks with multiple teams around the Overwatch League with a view to offloading DPS Pelican, support Seung-Hyun ‘Ir1s’ Kim and Tank Min-Jun ‘PIGGY’ Shin.
Despite their best efforts, the Outlaws have not yet managed to find suitors interested in these players. The same sources also stated that the Outlaws have been looking to move Pelican and PIGGY as a package deal.
Houston Outlaws
2021 Rookie of the Year Pelican is one of the players the Outlaws have been offering to other teams
A key reason for the Outlaws looking to ship three players, the sources noted, is Dante ‘Danteh’ Cruz’s wish to revert to his main DPS role. The North American player, who joined the Outlaws in 2018, has mainly played on Doomfist since Pelican’s arrival from Atlanta Reign at the end of last year.
The news will come as a surprise to many Overwatch League fans as the Outlaws currently sit fourth in the West standings with a 9-3 regular season record and made both the Kickoff Clash and the Midseason Madness playoffs. The team will take on the New York Excelsior on August 11 in their first Summer Showdown qualifying match.
We got our latest look at Pokemon Scarlet and Pokemon Violet tonight and a bunch of new information was revealed.
The biggest piece of information was definitely the fact that the Legendary Pokemon Koraidon and Miraidon will be available from the get go and they’ll act as mounts to get through the open world which is the brand new Paldea region. This includes driving, flying and getting through the sea on your trust Pokemon mount.
There are three modes of transportation:
Spring/Drive: Traveling through Paldea on foot can be quite the hassle. If you learn how to ride Sprinting Build Koraidon or Drive Mode Miraidon, you’ll be able to traverse the expansive Paldea region more freely and at full speed.
Swimming/Aquatics: On your adventure, you’ll be able to jump into rivers, lakes, and vibrant oceans to approach the Pokémon that live there or cross perilous waters in a snap by riding Swimming Build Koraidon or Aquatic Mode Miraidon.
Gliding/Glide: You can jump from mountains, towering cliffs or tall buildings and glide toward your destination. Not only does this offer you more options when choosing what to do, but you can also freely glide around and enjoy a view that you can see only from the Paldean skies.
We got another look at multiplayer which also includes the ability to get around the open world with friends on your legendary mounts alongside three friends.
There will be 8 gyms in the game which is one of the three stories that the game will feature. The other two haven’t been spoken about yet, but it was said that you’ll be able to go through the three grand stories as you see fit.
There will also be a greatly expanded Pokedex. We got a new look at new Pokemon including Wooper (Paldean Form), Fidough, Cetitan, as well as Tera form Pokemon (basically big crystal Pokemon) which are able to change types and enhance moves in Tera Raids (which seem to by like Dynamax raid).
THE CHEAPEST POKEMON SCARLET/VIOLET COPIES
Those that pre-order the game will be able to get a special Pikachu that cannot be caught in game. It knows the move fly and its Tera Type is flying.
Pokemon Scarlet and Pokemon Violet release on November 18th.
the sonic the hedgehog video games are more or less about one thing: blasting through a level with as much speed as possible. So as lovely as this Sonic-themed keyboard from Higround is, it seems almost antithetical to the spirit of the games, at least if you don’t have all your key positions perfectly memorized.
The keyboard is part of a new ‘capsule collection’ (yes, we’re just as upset about writing those words as you are about reading them) from Higround, who partnered with Sega to help pay tribute to the company’s most recognizable characters and one of its most beloved consoles.
The collection includes t-shirts, pants, bags, keycap sets, and even mouse pads, but the highlight definitely has to be the three heavily-themed keyboards. The most flamboyant of the bunch features elaborately decorated keys (with TTC Speed Silver switches underneath) recreating the iconic Green Hill Zone from the first sonic the hedgehogwhile a slightly more subtle alternative mirrors the key art for sonic adventure 2.
The last keyboard of the bunch pays homage to the Dreamcast, with the console’s logo on the space bar and the arrow keys matching the colors and labels from its controller’s action buttons. Each keyboard appears to be completely free from labels to prioritize the artwork on the keycaps, but in reality, the alphanumeric labels have been moved onto the side of each key for aesthetic reasons, prioritizing form over function. At least there’s some form of safety net.
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Amazon Fire 65″ 4K Smart TV
looks good Aside from being 65″ in size, this TV offers UHD 4K visuals which are a constant feast for the eyes, features HDR to make sure you can appreciate the full range of colors and contrasts, and it also allows you to use it as a hub for all of your streaming services.
Higround’s Sega collection officially becomes available starting at noon, PST, on August 5, through the company’s website. Wthread pricing hasn’t been revealed for any of the items yet, other keyboard releases from the company have ranged in price from $135 to $145.
Rigorous chemical treatments of pure bleached pulp are the most common approaches used to obtain cellulose nanofibrils. These processes incur significant expenses and are detrimental to the environment.
Study: Lignocellulosic nanomaterials production from wheat straw via peracetic acid pretreatment and their application in plastic composites. Image Credit: OskarsK/Shutterstock.com
A paper published in the journal Carbohydrate Polymers reports the synthesis of lignocellulosic nanofibrils (LCNF) using wheat straw (WS) feedstock. The LCNF shows great promise in bioplastic applications.
Cellulose Nanofibrils – A Green Alternative to Plastics
Products manufactured from green and renewable sources are in high demand. Cellulose, a plenteous natural resource, is renewable, non-toxic, and biodegradable.
Plastic detritus has accumulated because of the regular dumping of non-biodegradable plastics, causing severe contamination of terrestrial as well as marine environments. Cellulose nanofibrils (CNFs) are a more environmentally friendly alternative to plastics in a variety of applications.
The poor manufacturing volume and significant production costs of cellulose nanofibrils prevent them from reaching their true potential in different industries. Therefore, inexpensive and efficient production techniques must be developed to encourage the use of cellulose nanofibrils as viable alternatives to plastics.
How Are Cellulose Nanofibrils Synthesized?
Cellulose nanofibrils are typically made using bleached kraft fibers, a quality raw material providing nearly pure cellulose. The kraft fibers are mechanically fibrillated to extract the cellulose nanofibrils.
Mechanical fibrillation processes require a considerable amount of energy. To advance the fibrillating phase and minimize energy needs, pre-treatment procedures may be used.
An extensively used pre-treatment process for synthesizing cellulose nanofibrils is TEMPO (2,2,6,6 Tetramethylpiperidin-1-oxyl) oxidation. This technique stimulates cellulose fiber oxidation, which increases the charge density on their surface. This ultimately leads to electrostatic repulsion among the cellulose nanofibrils and yields significant fibrillation output.
Drawbacks of Using TEMPO
The downsides of employing the TEMPO oxidation technique include substantial chemical expenses and the toxic nature of TEMPO. Moreover, costly removal methods like dialysis are required to eliminate small quantities of leftover TEMPO from the cellulose nanofibrils, making scalable application of the approach quite difficult.
Fabrication of cellulose nanofibrils needs a more economical conversion technique if the scalable implementation of CNFs is to be achieved.
Developing Lignocellulosic Nanofibrils with Wheat Straw
To avoid the drawbacks of TEMPO oxidation, fabrication of LCNF may be the key. LCNF production requires less expensive lignin-carrying feedstock rather than completely bleached pulp. Moreover, moderate treatment procedures may suffice for LCNF, resulting in high-output products comprised of lignin, cellulose, and hemicellulose constituents.
Production of wheat creates a byproduct known as wheat straw. WS contains the residual stalk left after the harvest of the wheat grains.
Wheat straw acts as a suitable raw material for the manufacture of LCNF because it is abundantly available. Being an agricultural leftover, the expenses of using wheat straw are much less as compared to other raw materials.
Wheat straw therefore provides a low-cost and plenty of non-wooden fiber resource to produce LCNF.
Advantages of Peracetic Acid Treatment
Peracetic acid (PAA) is a biodegradable reagent that can engage in reactions with lignocellulose biomass at temperatures less than 100 °C. Therefore, using PAA for pre-processing of LCNF appears to be a viable strategy.
PAA treatment produces greater yields because of its high oxidizing capability, which selectively eliminates lignin while preventing solubilization of the carbohydrates.
Peracetic acid can trigger the oxidation of the reducing parts of carbohydrates, which results in a negative charge on the surface. This could aid in the nanoscale fibrillation process and produce stable colloidal suspensions.
Compared with the traditional TEMPO oxidation process for cellulose nanofibril synthesis, peracetic acid treatment provides several benefits. PAA has lower toxicity and is ecologically friendlier than TEMPO, and it allows more control over the removal of hemicellulose and lignin from the pulp material.
The architecture and content of nanofibrils generated by peracetic acid treatment differ significantly from the cellulose nanofibrils produced by traditional TEMPO oxidation.
Applications of Cellulose Nanofibrils in Plastic Composites
Cellulose nanofibrils may be utilized as reinforcements in plastic composites to minimize the quantity of petroleum components while also improving the characteristics of the plastic composites.
Hydrophilic and biodegradable polymers, like polyvinyl alcohol (PVA), show weaker mechanical characteristics than their synthetic alternatives, necessitating the addition of different additives to improve their qualities.
Higher aspect ratios and better interface interactions with the polyvinyl alcohol array enable cellulose nanofibrils to enhance the mechanical properties of PVA nanocomposites when introduced in small quantities (<5% wt.).
Results of the Study
The team showed that it is possible to fabricate lignocellulosic nanofibrils having excellent plastic reinforcement characteristics using low-cost agricultural residue. They achieved this by alkaline peroxide pulping, after which the LCNF was treated with PAA.
The lignin and hemicellulose parts of the nanofibrils, formed using wheat straw, were retained, which was critical for enhancing productivity.
While the PAA treatment generated nanomaterials with a lower charge density on the surface than TEMPO oxidation, the material characteristics were unaffected. All specimens demonstrated high colloidal stability under aqueous conditions.
PAA-treated materials improved thermal stability due to their decreased charge density and increased lignin level. Furthermore, irrespective of charge density, all nanofibrils dispersed well in the polyvinyl alcohol matrix. This enhanced the tensile strength and Young’s modulus of the composites, showing a unique case of concurrent strengthening and toughening.
The study established a novel way of producing lignocellulosic nanofibrils from agricultural residue. This economically feasible approach has the potential to enable scalable production of nanomaterials with commodity product costs, allowing them to be used in high-volume industries like bioplastics.
Reference
Pascoli, DU, Dichiara, A., Roumeli, E., Gustafson, R., & Bura, R. (2022). Lignocellulosic nanomaterials production from wheat straw via peracetic acid pre-treatment and their application in plastic composites. Carbohydrate Polymers. Available at: https://doi.org/10.1016/j.carbpol.2022.119857
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