This one’s for my kids, specifically the Junior Mad Scientist and the Little Man. Remember how I told you that they are looking for people to specialize in Materials Sciences, and you both looked at me funny? Well, these might help you understand just how cool, and diverse, that field is. Also, there are scholarships and grants for college going begging in this field. So! check it out, and if this whets your curiosity, I’ll find more stuff to read and do experiments with. Especially experiments, because hands-on is fun.
You might not think of sugar as being a material to build with. But in this case, it’s being used as a coating and it made the underlying structure stronger, as well.
Hong, Hyo-Wan Anh, and their colleagues wanted to make antibacterial films for plastics that would endure conditions in the mouth, which has a hodgepodge of enzymes and varying pH.The films would also need to be safe for oral use and made with easily available materials and simple synthesis methods. They chose to create a multilayer film made of two polysaccharides: chitosan, which is derived from crustacean shells, and carboxymethylcellulose, a common thickener used in food and pharmaceuticals.
They used an approach called layer-by-layer assembly, which consists of electrostatically depositing alternating layers of opposite charge onto a surface. They deposited five layers each of negatively charged carboxymethylcellulose and positively charged chitosan onto sheets of polyethylene terephthalate (PET), the transparent plastic used to make most dental devices. This resulted in a clear, 1.8-µm-thick coating. The carboxyl groups in carboxymethylcellulose and the amine groups in the chitosan are superhydrophilic: They attract water, creating an ultrathin, smooth water film on the plastic surface that keeps bacteria from sticking
Jose Chirino, technical director for the High Performance Materials business unit at Lanxess, believes his company offers a solution. “We have been active in the automotive industry for many years, implementing glass-filled, nylon-based polymers to replace metal in structural components,” Chirino says.
For example, Lanxess has developed a high-temperature-stabilized polyamide that can withstand temperatures up to 230 °C. When combined with 35% of glass fibers, the product is ideal for making parts that need to withstand high temperatures, such as intake manifolds.
Coatings, strong but light frameworks… how about growing some cushions? Yup, you can do that with fungus. If you follow the link, you can do almost anything with fungi… Little Man, you don’t have to eat it. This scientist doesn’t like the texture any more than you do!
More recent innovations have moved fungi applications from the reductionist use of individual chemicals to a holistic use of the entire organism. Commercial examples range from small—eco-friendly shipping materials and vegan leather for shoes and purses—to large, with biodegradable fungi insulation and custom-molded furniture.
And of course, the wave of the future use of materials to make things, from engine parts to human organs and beyond is 3D printing. While you’ve seen it done – and designed projects to be printed! -with hard plastic resin, scientists are working hard on being able to print with liquid.
in fused deposition modeling, a 3D digital computer-aided design (CAD) model is converted into a physical object through layer-by-layer deposition of thermoplastic by melting of a solid filament. After deposition, the plastic rapidly cools and serves as support for the next layer, allowing the object to be built from the bottom up. While conceptually straightforward, success requires specific combinations of materials properties and printing process parameters to meet application criteria [4]. The search for the right parameter combination can become even more complex with new materials and new 3D printing methods. For example, silicone elastomers have emerged as a viable material for applications in wearable sensors and medical devices, yet these polymers are often liquids before crosslinking and face gravity-driven collapse using traditional 3D printing. Recently, our group and others have reported new approaches to soft material 3D printing by depositing material within a sacrificial support bath [5–7]. We have termed this process freeform reversible embedding (FRE) [6]. In FRE the support bath is a yield stress fluid; above its yield stress, such as that applied by the nozzle, the bath fluidizes and allows deposition of the printed material. Then, once the stress is relieved with the passage of the nozzle, the support bath resolidifies into a viscoelastic solid, and holds the print in place. After the printing is complete, the liquid polymer is crosslinked and can then be removed from the bath as a free-standing object.
Far from being boring and obscure, this is a really cool field of study. I think that if you’re both still considering engineering, you should look at these links to articles and papers. Also, look up a broom bot. It made me laugh, but it would be a great project later this summer. We could see how Tricksy reacts to a small robot chasing her!
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14 responses to “Material Excitement”
Ga Tech offers under and post graduate degrees in Material Sciences.
As does Wright State (providentially located next door to Wright-Patt AFB), and it was at a talk there I heard a dean practically begging for students to take Material Science, which made me pay attention. Evidently it’s a growing field but so poorly known it doesn’t attract graduates.
My employer, NDSU, also offers degrees in Coatings and Polymeric Materials. According to their webpage “The department provides the only academic research focused on polymer organic coatings in North America, and is one of only very few such departments in the world”
Very cool. Makes me wish I could A. hack the math and was B. young enough to explore options.
Yeah, math ain’t my strong suit anymore. In high school I was pretty good at math. Got to college and started doing calculus and …well, I knew there was a relationship there, but I just couldn’t see it like I could with algebra, geometry and and trig. When I got to Diff EQ it was obvious I needed to change majors.
and c. hadn’t just finished a degree?
Well, I do want to pursue a Master’s. But not in this I think.
A masters in my field just means you teach, and i really didnt want to get stuck teaching in CA.
And in mine it makes it more likely I’ll be able to do research, or advance up the career ladder, depending which leg I choose.
in the middle of my Sophmore year the guy teaching my science classes told me i cold probably make it through an Engineering (or at least engineering tech) major with some math coaching, but by then i was committed to the course i was on, largely because the credits i had wouldn’t transfer at that point.
That is so interesting. Makes me wish for a time machine.
Hmm. Could that nonstick-for-bacteria coating be adapted to coat natural teeth as well as plastic?
[There used to be a fluoride paint that made your teeth plaque-proof for ~3 years, but no dentist today seems to remember it. Tasted sour like nothing else you’ve ever had in your mouth, but man did it work.]
Back when Pa did injection molding (from machining the mold to delivering to finished parts) one place was terribly concerned about how “that cheap plastic” (why did they go with it then, hrm?) would perform. So.. nylon which, aside from UV issues, is pretty hardy stuff. And glass fiber filled, up to the maximum that was available or that the machinery would take. And then the first sample were delivered. And tested. And sure enough, something snapped and parts of the assembly went flying… “Cheap plastic…”
BUT then someone walked over to see just what broke and where. The fiber-filled nylon had held. The steel pin they were sure wouldn’t be any trouble? That failed. Not another word about “cheap plastic.”
I still occasionally see someone our age make fun of “The Graduate.” Really! One of the few Hollywood films that was actually bang-on prophetic!