I'm not trying to put the scare into anyone. But something isn't right about Teflon .
And if you google, you get hits like "Teflon linked to birth defects and illness; but is it safe to use in cooking?"
I do not think there's any harm using Teflon-insulation for cables. Should you decide not to use Teflon, it should be because of greater environmental issues, like manufacturing, and, perhaps, that triboelectricity thing.
And if you google, you get hits like "Teflon linked to birth defects and illness; but is it safe to use in cooking?"
I do not think there's any harm using Teflon-insulation for cables. Should you decide not to use Teflon, it should be because of greater environmental issues, like manufacturing, and, perhaps, that triboelectricity thing.
I would encourage you to analyze the source of your information regarding fluoropolymers, phn. I'm not saying they have a malicious agenda, but they are not the most well qualified scientific pannel to analyze the impact of these materials. The best evidence I have seen on fluoronated hydrocarbons is that they are safe when handled properly. They are innert when polymerized, and though there are indeed environmental concerns (especially when heated), the dangers of gasoline and the impact caused to your system by pumping a tank of gas grosly outweighs a lifetime's proper use of teflon.
Just food for thought.
Still, if anyone is concerned, they still do make cast iron cookware!! I am still using some of the stuff my grandmother got when she was young.
Just food for thought.
Still, if anyone is concerned, they still do make cast iron cookware!! I am still using some of the stuff my grandmother got when she was young.
Teflon makes superb audio capacitors; extremely clean and perhaps slightly warm. Next step up from polystyrene, but substantially more expensive. Used where extremely low DA is needed, such as sample and hold circuitry, and also of course in high temperature environments. Drawback is that the related low Dielectric Constant makes for large capacitors.
The harmful qualities of teflon is an urban legend that's been around for 30 years that I know of. The extreme bonding of fluorine makes it very difficult to break the bonds. Good luck on doing so at cooking temperatures. If it caused flu-like systems, half of America would be staggering around, and someone might have noticed by now.
There is a material used in the manufacture of teflon that is harmful, has escaped factories, and is subject to stronger restrictions as it is being phased out. But it is not present in the final product, although it wouldn't hurt to wash your new non-stick pan before using it.
The harmful qualities of teflon is an urban legend that's been around for 30 years that I know of. The extreme bonding of fluorine makes it very difficult to break the bonds. Good luck on doing so at cooking temperatures. If it caused flu-like systems, half of America would be staggering around, and someone might have noticed by now.
There is a material used in the manufacture of teflon that is harmful, has escaped factories, and is subject to stronger restrictions as it is being phased out. But it is not present in the final product, although it wouldn't hurt to wash your new non-stick pan before using it.
I respectfully disagree. This is not an urban legend. I'll try and prove my point below, but if this isn't coherent, I am at the end of a VERY long day in my lab, so bear with me (BTW, I am working in my chemistry lab as I type this, so if you want a more in-depth discussion of this topic, I am sure I can pull one of my old polymer text books off the shelf and get a little deeper if we need to. . . )Curmudgeon said:
Here's some quick chemistry background: carbon-fluorine bonds are indeed pretty stable (~110 kcal/mol for fluoromethane), but fluoropolymer degradation pathways typically follow carbon-carbon bond cleavage pathways (ball park those at 80 kcal/mol). Though the electronegativity of the fluorine does impact the bond strength of the carbon polymer backbone, it does NOT do so to an extent to prevent polymeric breakdown at reasonable temperatures. Thus, though the C-F bonds are indeed IN the polymer, the "extreme bonding of fluorine" isn't directly responsible for the stability of fluoropolymers.
Typical hydrocarbon polymers (let’s take polymethylmethacrylate, or plexiglass) under a glass transition phase change upon heating in which solid plastics begin to exhibit better flow characteristics. If you heat further, like most hydrocarbons, they will catch on fire and burn, undergoing a combustion degradation.
Fluorocarbons (let’s take polytetrafluoroethylene, or PTFE, for example, since it is pretty simple and it’s what’s most commonly applied to cookware), on the other hand, still undergo glass transitions, but will not ignite! Rather, the non-flammable gasses will be evolved. This is not to say that fluoropolymers can’t self combust, but it is not as common as with hydrocarbon polymers.
Let’s bring in some experimental evidence:
http://www3.interscience.wiley.com/cgi-bin/fulltext/109617130/PDFSTART
Especially interesting are the thermo-oxyluminescence studies (see page 56). At ~350 C (~660 F for us Americans) particle emission becomes apparent. This is WELL within the range of temperatures reachable on a common household cook top in a bare pan on high heat. The calculated activation energy for this process is 56 kJ/mol (or about 13.4 kcal/mol to keep units consistent within this argument) which roughly corresponds to the breakdown of the polymeric backbone into lower molecular weight, gaseous products. We’ll leave the discussion of what those products are for another time if we really need to get into it.
So why is it that a typical CC bond is ~80 kcal/mol but it only requires 13.4 kcal/mol to break down a CC bond based polymer? Well, since the cleaved bonds re-form other bonds, the thermodynamics of the new bonds help offset the energy required to cleave the initial bond. Remember, we aren’t doing this chemistry in a vacuum.
So, what’s the moral of the story?
If you are using a Teflon pan for cooking veggies or sauces or something else below ~400 F, then there is little danger of releasing toxic chemicals. If, however, you want to sear, blacken, or leave the pot on the stove with nothing in it, you are running the risk of degrading the fluoropolymer coating on your non-stick pan and releasing bad stuff into the air you are breathing. No urban legend to it.
Interesting...what harm can occasional scraping with non-plastic tools do (to make cuts into the coating)? Is the pan potentially dangerous from that time on?
What if a pan is over-hrated once, but the used "for veggies"
What if a teflon pan is very old and worn, is it more dangerous?
Cheers to dfdye
What if a pan is over-hrated once, but the used "for veggies"
What if a teflon pan is very old and worn, is it more dangerous?
Cheers to dfdye
That is just mechanical damage. The polymer will still be inert and non-toxic. If it starts to flake, you probabaly don't want to ingest the flakes, so I would toss the pan, but as long as it is just a scratch (or several) and the coating isn't peeling, it should be fine.Zombie said:
The gas release is heat activated, and does not continue once the polymer is cooled. It will be fine.
Not that I know of, but I must admit that I have not seen long term thermocycling data for PTFE. Based on what I know about OTHER materials like Delrin, as long as the material isn't stressed past its breakdown threshold, it should be fine undergoing continual thermocycling.
Thanks.
Any cooking pot can vouch that if a non-stick pan is heated too much on the stove the coating will discolor and the pan will release yukkie fumes. That scent also goes into the food that is fried in the pan. After a non-stick pan has been overheated it is better to toss it cause the teflon taste will haunt you.
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