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Wetting problem

 

Wetting problem! I need something to prevent liquid cling and accumulate around glass capillatory tubing(OD:500um). The property of liquid is like water. I heard that Teflon coating is the best way to come over(preventing accumulation of liquid around the outlet of tubing when it is dropping from the tubing). It would be good if Teflon coating is dried out easily. Thanks.

Your advice will be a great help to my experiment.

Se-Jung Moon
UIUC - Urbana, Illinois, USA

That's a mighty small tube! Would it be possible to alter the surface tension of the liquid (ie: a surfactant additive) so that it won't bulb up when it hangs from the tube? Just a thought. Good Luck.

Dan Brewer
chemical process supplier - Gurnee, Illinois

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Hi Se-Jung,

You did say or at least infer 'outside', didn't you?

What Dan Brewer suggested sounds like a very good idea.

But why glass? Why not use pure teflon? Why can't you wax the outside and then polish it? That, too, would deter wetting out and promote tracking.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

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If you can't alter your liquid by adding something to break the surface tension, could you use something like Teflon mold release sprayed on the outside of the capillary tube? With the size tube you are talking about, the Teflon spray may make the outside just hydrophobic enough to accomplish your task. I have used Teflon mold release by Miller-Stephenson when we needed a bit of Teflon temporarily deposited on something as a lubricant or mold release. (TFE Release Agent--MS-122/CO2) You would have to test your liquid to make sure that after you sprayed the capillary tube and dipped it in your liquid that nothing was left behind..... As far as I know,the product is just TFE with a CO2 propellant. Not very expensive and very easy to use.

Ronna Erickson
- Amherst, Massachusetts