Teflon, while it seems like a material in a weird class of its own, is actually just the fluorinated analogue of polyethylene - milk jugs and Saran wrap.
Fluorination, however, does funny things to molecules. Difluorine, or F2 is an absurdly reactive molecule. It has a lot of energy to give up in oxidizing a substrate. The flip side of this is that fluorinated molecules tend to be in a deep thermodynamic well (and therefore very inert). For this reason, PTFE is used in cookware coatings and electrical insulation.
The other thing about fluorination is that it confers certain odd colligative properties to materials. Perfluorinated (maximally fluorinated) materials tend to be hydrophobic AND lipophobic, but very fluorophilic. This is why oil and water both bead on teflon. The last third of it, fluorophilicity, is poorly understood (and still being researched). See here for a neat example of something weird that will only every happen with a fluorinated material.
One neat thing about fluorous substrates is that they provide a possible means for purification. Since fluorous sticks to fluorous, you can attach something removable and fluorous to your molecule, flow a solution of it over something fluorous and solid, and later remove it from that solid support. This is a potentially pretty powerful (and singular - we don't get any new light elements, so there's never going to be anything else remotely like fluorine, ever) means of purification, one of the cornerstones of chemistry.
Sorry for the spotty updates - the Internet is still flaky at home. I have no idea what's up. See you tomorrow, hopefully.
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I was just curious about your specialty. Most of the molecules you write about are organic, but Page 3.14's Periodic Table of ScienceBlog's lists you as an inorganic chemist.
No, inorganic chemistry definitely isn't right. "Physical science," the supercategory, sure is, though. Maybe biology, too.
I work in biophysics, which (for me) means I'm one of those guys who never made up their mind and straddles a few subdisciplines, for better or worse. Specifically, I'm interested in nucleic acids.
On an average day, I'm either trying to synthesize a molecule that's either a bit of DNA or very closely related, or trying to ligate it and make modified bits of DNA. I'm sure my subspecialty at MoTD U is biophysical chemistry, but my day-to-day work/thinking tends to be bioorganic chemistry, with a strong physical bent, with the (very) occasional foray into molecular biology.
For example: today, I was working with a CPG (controlled pore glass, the stuff that we use to make oligonucleotides) resin and an RNA phosphoramidite, trying to make a chemically modified RNA. Tomorrow, I'm going to try and attach another functional group to the resin. Later, I'll try and ligate it to existing RNAs (or maybe DNAs). Maybe eventually we'll try and figure out how small molecules bind to it.
No metal ions were harmed in this synthesis. It's a living.
Do you know anything about the dangers of cooking with teflon? I hear a lot of rumors about it being really bad for you, but mostly from people who are eager to embrace any new-ish technology as being evil, and I'd like to learn more about it from someone who understands the chemistry.
I second that question about teflon and its safety for cooking.
I am not a scientist, but when in doubt I feel it is best to avoid the product. I was constantly getting what I thought were sinus headaches and found out they were triggered by all the cleaning spray that I was using. I have thrown out all my teflon and finally after much searching found a Ceramic pan that is made in Italy by a company called Moneta. They directed me to a website www.gocookware.com where I was able to purchase one. I have never seen pans like these and now own three.