Sciencemadness Discussion Board

Glassware without crafting nor buying it ?

Arthis - 17-11-2002 at 09:56

Hello everyone.

Like almost all of us, we always wanna have much glassware, and it's not always easy to obtain all you want, like a particulary condenser or whatever. I was wondering if anyway it would be possible to use standard glass tubes and use teflon (PTFE tubes) to make them hold together.

I know that teflon is particularly resistant to corrosion and heat, and has excellent chem. properties. The fact is I'm wondering whether it could be well suitable for making a condenser for example.
Imagine just 2 tubes, 1/3'' by 1' another 1' by 2/3'', one inside the other, and linked by a teflon cap.

But wouldn't it be damageable any way ?
That would be the easiest solution to have a lot of glassware without having to pay lots of money. Just need to buy glass tubes and teflon tube. The first shouldn't be expensive, but the second ? Is PTFE tube expensive ?

That's all fox, have a nice day, I'm going to work.

IodineForLunch - 23-11-2002 at 18:45

I'm pretty sure teflon (like many plastics and polymers) has poor heat conductivity, and thus would not be suitable for a condensor.

David Hansen

kingspaz - 24-11-2002 at 09:52

poor heat conductance or not if you run say 3m of PTFE coiled into a spiral through the running water stream that should be sufficient. lower heat conductance just means you'll need more time for the heat to be removed and thus a longer tube.

teflon and glass

Organikum - 16-2-2003 at 04:15

One problem which may occur if glass and teflon is combined depends on the fact that teflon has a extremly high thermic expansion rate, glass a extreme low one. So a perfect fitting stopper in a glasstube can burst the tube by heating.

On the other way this might be a perfect way to fix glass and teflon tubes together provided that the teflontube has thin walls to compense the differences.

But anyways you can use PVC or PE/HDPE most times and this costs near nothing.



mick - 9-10-2003 at 09:54

PTFE is great with glass over about a 50oC range. Then they start sticking. PTFE creeps, especially under vacuum and warm.
PTFE is the most chemical resistance stuff known to man.
If you heat PTFE over about 250oC you could make HF gas (possible test, put it on the corner of a tile, warm it until it just starts going clear and white smoke, cool, if the tile is etched, its PTFE, do not inhale at this point.

Hermes_Trismegistus - 28-11-2003 at 01:10

Virgin Teflon is neither particularly easy to work nor is it CHEAP!

If you can procure borosilicate tubing, WHY not condensers?

Try LABX for wonderful used anon supplies!!!