I came up with an idea when handling these 0.75mm thick teflon plates at my local store. Could one use to cut round platelets and insert them on the
inside of any normal plastic bottle tops and screw them tight against the glass mouth of the bottle to hold against harsh chemicals? Please see image
if you didn't get my point.
smaerd - 27-11-2012 at 14:51
I didn't know hard-ware stores sold teflon plates. I usually use PTFE 'plumbers tape' for the same purpose for small vials.chucknorris - 27-11-2012 at 15:29
At us they sell HDPE, PTFE, viton and other plates from 0.5mm to 30mm thickness, although the price is rather nasty and they must be pre-ordered to
the local market.
But that the concept itself should work? I can get all sort of bottles, cans, jars, jugs and shit for few cents a piece, but man do their caps hold
anything next to tap water, nope. The glass will hold just any shit, but I once put nitric acid in one can and the bottle top was literally vaporized
in less than 24 hours. cyanureeves - 27-11-2012 at 16:08
1" teflon tape could work also and i dont see why that teflon plate shouldn't work if it covers the mouth of the bottle entirely.i have stored nitric
acid in an amber vitamin bottle with original cap for over a year with no problem. DCM was another thing though because it sucked a vortex about two
inches deep until it eventually broke through. funny thing was that every other day or so i would check the bottle cap at the inverted tit looking
vortex and it was always hard and stiff yet it looked like it was soft and had melted inwards.
[Edited on 11-28-2012 by cyanureeves]chucknorris - 27-11-2012 at 17:28
My case could be a reason because the nitric was white fuming.
Teflon tape is OK, but I think it could chafe through eventually while the 0.75mm plate will withstand harsh use almost forever. watson.fawkes - 27-11-2012 at 19:01
I can get all sort of bottles, cans, jars, jugs and shit for few cents a piece, but man do their caps hold anything next to tap water, nope.
The problem I anticipate with cheap bottles is that the circular opening that the PTFE disk would seal
against is not particularly planar. The more out-of-plane that opening is, the more deformation you need in the disk to get a good seal. That means a
more flexible material, more force by the cap against the disk, or a thinner disk. None is desirable.
You could easily grind the openings flat with the kind of machine used for lapping or lens grinding. With some patience and a simple jig you might do
it entirely by hand on a properly flat surface.Dr.Bob - 27-11-2012 at 19:22
This will work for some chemicals, but the chemicals might still attack the cap, so the cap has to be resistant to the chemical to a large degree.
So simple solvents might work fine, but for some chemicals, like Br and SOCl2, the cap must still be very sturdy and resistant. They do sell special
caps for media bottles for instance, which are just a harder plastic with a fluoropolymer liner in the cap. We have even replaced them before with
replacement liners made of sheet Teflon like material. Teflon itself does not form good liners, too hard and deformable, but other ones work OK.
Gore made some amazing materials for this, but the cost was astronomical. But they could resist almost anything.
