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Plastic That Changes Shape In Light
JLavezzo writes "Picture a flower that opens when facing the sunlight. In work that mimics that sensitivity to light, MIT Engineer Robert Langer and his German colleagues have created the first plastics that can be deformed and temporarily fixed into shape by light. This material could one day lead to medical devices that build themselves inside a patient's body, or door latches that can be opened with a flashlight. Additional commentary available at The Science Blog"
They, the scientists, have been able to do this for some time with
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heat. The link below is to an article that shows a 30 gram weight
being lifted and lowered by a type of polymer know as nematic
elastomers.
http://www.sciam.com/article.cfm?articleID=0007
they also say in the above article(link) that, "..light can also induce
shape changes anywhere from 10 to 400 percent [in the polymer]."
However, it takes a hours for it to return to the original shape.
One of the best applications,in my opinion, for any fast-acting shape
changing polymer would be as artificial muscles. Not sure how
practical or easy that might be. You would have to get the temperature
range, where the shape changing takes place, down pretty low and find
a way to control it outside of the body's heat influence. I am sure
there are other problems as well.
--greg Vulcan quiescent... Q: What machine shutdown with this message?
I thought you couldn't light the inside your body.
I was under the assumption that was the one place the sun don't shine.
liqbase
No Flash Photography Please
I had one of those Star Wars Speeders that fit Luke and Ben Kenobi action figures as a kid. It was all plastic. I accidentally left it on the dashboard of my mom's car during a sunny day.
Sure enough, light changed its shape irrevocably.
Just to clarify... this plastic changes shape in response to various wavelengths of light... not the quantity, as has been previously done. (Note - the older technology has been adapted for cell phones, too)
HIV Crosses Species Barrier... into Muppets
This could be the ultimate cure for geeks. Simply wear special plastic goggles that restrict vision (and hence computer access) if wearer does not go outside.
The toad can't burp - and for some reason can't fart either, so it swells up and eventually explodes. --Anonymous Coward
Personally, I'd like some self-adjusting miniblinds.
"No fair, you changed the outcome by measuring it!" - Professor Hubert J. Farnsworth
This could allow retail level solar panels to eek out the equivalent to an additional 2 hours of peak sunlight over a 12 hour period. Initially this would appear to be a 10% improvement but in reality it is closer to a 30% improvement (I will leave it as an exercise for the reader to integrate sin(x.pi/12) from 0 to 12 hours [flat panel on the ground with the sun passing directly overhead] to yield 6.28).
I should imagine the cost of the plastic is going to be far less than the processed silicon for solar cells.
da ZombieEngineer
OSU had developed light-tunable plastic magnets. Here the plastic material becomes 1.5 times more magnetic when blue light shines on it. Green light partially reverses that effect.
Another interesting work is from PSU on PLZT, this new material shows a large piezoelectric effect in response to near-ultraviolet light. Piezoelectric materials convert electricity into mechanical energy -- movement. When an electric current is run through piezoelectric ceramic, the ceramic changes size -- it shrinks or expands. Certain ferroelectric materials exhibit stronger photovoltaic (light into electricity) effects. Combining these ferroelectrics with piezoelectrics (electricity into motion), researchers created a single material that would convert light directly into motion.
You have to appreciate the mind of a scientist.
Scientist1: Dude, look at this plastic. When it comes in contact with ultraviolet light, the plastic forms bonds with itself, causing it to change shape.
Scientist2: Awesome! If you hit it with another frequency, the proccess reverses itself.
Businessman: Hm. What sort of applications do you think this could have?
Scientist2: App-li-kay-shuns?
Scientist1: Uh, you could make toys out of it. Or... maybe like you could have it bend into... uh... medical things. For medicine.
Businessman: I'm cutting your funding.
Scientist1: WHY DON'T YOU LOVE ME?!?
"Never attribute to malice that which can be adequately explained by stupidity." -- Hanlon's Razor