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Self-strengthening polymer nanocomposite works best under pressure
No one keeps carbon nanotubes down -- especially not these guys. The always popular allotropes have been enlisted by researchers at Rice University to create a composite material that gets stronger under pressure. When combined with polydimethylsiloxane, a rubbery polymer, the tubes form a nanocomposite that exhibits self-strengthening properties also exhibited in bones. During testing, the team found the material increased in stiffness by 12 percent after 3.5 million compressions. Apparently, the crew is stumped on why it reacts this way, but is no less eager to see it working in the real world -- discussion is already underway to use the stuff as artificial cartilage. And here we thought aerogel was cool. Full PR after the break.
Shape-memory polymer knows when it's hurt, fixes itself
We're no strangers to the futuristic catch-all idea of 'self-healing' -- it's one of the basic tent poles of many conceptions of tomorrow. That said, researchers are currently hard at work at Arizona State on a material that -- you guessed it -- can detect when it is damaged and, of course, heal itself. Though we sound a bit incredulous, the science is pretty simple here, and the progress on the project is very real. The material uses what the researchers are calling 'shape-memory' polymers and have a fiber optic network embedded within them which acts as the damage sensor as well as the heat delivery system. The polymers return to a pre-defined shape when heated to a certain temperature, and, when damage is detected, an infrared laser sends light through the network to the damaged area, triggers the shape-memory, and commands the area to repair the crack or tear -- regaining up to 96 percent of its original strength. The so-called autonomous adaptive structures are part of a long-term research into shape-memory healing which could impact long-term developments of implantable medical devices, for instance. A video of the shape recovery process is after the break.
NC State's refreshable Braille display could revolutionize reading for the blind
While many in Raleigh are wondering whatever happened to the glory days of 1983, Dr. Neil Di Spigna and company are doing far more productive things at NC State. It's no secret that the holy grail of Braille is a tactile display that could change on a whim in order to give blind viewers a way to experience richer content (and lots more of it) when reading, but not until today have we been reasonably confident that such a goal was attainable. Gurus at the university have just concocted a "hydraulic and latching mechanism" concept, vital to the creation of the full-page, refreshable Braille display system. As you may expect, the wonder of this solution is the display's ability to erect dots at the precise points, retract them, and re-erect another set when the reader scrolls through a document or presses a "link" on a website. We're told that the researchers have already presented their findings, and if all goes well, they'll have a fully functioning prototype "within a year." Here's hoping a suitable replacement to Lee Fowler is also unearthed during the same window.
New materials change color when stressed, making fans of mechanochemical transduction positively giddy
A U.S. Army-funded research project at the University of Illinois has developed a material that changes color when it is met with force or becomes overstressed. Among the examples trotted out in this month's issue of Nature are an elastomer that starts out the color of amber and turns progressively more orange as it's pulled, eventually turning red as it reaches its point of failure and snaps (see the photo on the right). Once relieved of stress, the material reverts to its original color -- and it can be used multiple times. Suggested uses for this technology include parachute cords, climbing ropes, coatings for bridges -- anything, really, that you'd want a heads-up on before imminent failure. Pretty wild, huh? [Warning: Read link requires subscription.][Via CNET]
Self-assembling polymer arrays could lead to larger hard drives, boastful Badgers
Most folks up in Madison are readying their face paint and stocking up on tailgating supplies, but the geeks among us (bless 'em!) are focusing their attention on something much more relevant to your future RAID array. A team from UW-Madison (along with partners from Hitachi) is getting set to publish a report that details a patterning technology that could offer performance gains over current methods while reducing time and cost of manufacturing. The process builds on existing approaches by "combining the lithography techniques traditionally used to pattern microelectronics with novel self-assembling materials called block copolymers." So, what does all this technobabble mean for you? Huge gains in density on patterned media, or if that's still not straightforward enough, ginormous HDDs in the near future.[Via Protein OS]
Graphene-polymer hybrid composites look to oust carbon nanotubes
We're pretty certain the world's big enough for the both of 'em, but a graphene-polymer hybrid developed by a brilliant team from Northwestern University could prove to be a suitable -- and much cheaper -- alternative to polymer-infused carbon nanotubes. Put simply, graphite can be purchased for dollars per pound, while single-walled nanotubes are hundreds of dollars per gram. A breakthrough has found that tough, lightweight materials can be created by "spreading a small amount of graphene, a single-layer flat sheet of carbon atoms, throughout polymers," and these composites could eventually be used to make lighter car and airplane parts (among other things). We won't kid you, there's a lot of technobabble in the read link below, but it's well worth the read if your inner nerd is up for it.
Researchers develop scalable circuit printing technique
As if there weren't enough "almost theres" in the world of printable circuits, now we've got yet another team developing their own iteration of a printing press for electronics. The group, which includes scientists from DuPont and Organic ID, has reportedly "fabricated a printing plate used to print the source-drain level of an array of thin-film transistors," essentially solving some of the low-resolution constraints seen on prior competition. The goal is to eventually posses the ability to "print large, flexible circuits using machines similar to printing presses," and while it seems to be a ways from commercialization, initial testing and comparisons to more traditionally-created transistors have produced glowing results.[Image courtesy of HowStuffWorks]
AIST turns transparent glass into mirrors to conserve energy
We've seen two-way displays and undercover mirrors before, but the latest two-faced invention to come from the depths of the National Institute of Advanced Industrial Science and Technology (AIST) can pull double duty in regard to purpose and save a little energy in the process. The "switchable glass" has certain reflexive properties created by the twin coatings of "40-nanometer-thick magnesium-titanium alloy, plus a 4-nanometer-thick layer of palladium," which allows for the mirror to become transparent when a small amount of hydrogen is introduced between the two panes. Alternatively, tossing in a bit of oxygen forms a reflecting mirror, allowing users to "switch" the glass by injecting gases. Contrary to other commercialized approaches, this rendition can purportedly result in up to a "30-percent savings in energy costs" by having to run your air conditioner less, but there's still work to be done. Scientists at the AIST are still toiling away as they try to fight the relatively rapid deterioration that occurs from "frequent switching," but if they can add a dash of durability and get the price down to a respectable level, we could all be living in a house of mirrors before too long.[Via PlasticBamboo]
