Sciencemadness Discussion Board

Sulfuric Acid resistant Glue/Adhesive

Hilski - 25-5-2012 at 08:40

I need to affix a small glass container to the bottom (inside) of a larger glass container. I need to come up with a glue/adhesive that is resistant to 40% - 60% H2SO4, at between 40 and 80 degrees C. I'm sure I can find something that will work, but I wanted to see if anyone here had any recommendations for my specific requirements.
It would be nice if it was something I could pick up locally, and not have to order it online, but I'm open to all suggestions. I live in a major city in the US, so pretty much every store you can think of is within reasonable driving distance.

Thanks is advance.

[Edited on 25-5-2012 by Hilski]

Pyro - 25-5-2012 at 09:04

put amounts of different glues on something, a microscope slide for example, and put them in the acid at the required conc. and temp.
then just look and see if there is any visible reaction, or if it is weaker afterwards

Mailinmypocket - 25-5-2012 at 09:52

You could take say, 10mm lengths of glass tube, and dip one end very slightly in various glues. Then submerge the coated tip into a beaker of the acid... then wait to see if any of the glues or sealents fail by watching for the tubes filling with acid due to atmospheric pressure. That way you not only see if the material degrades but it also shows if it maintains a good adhesion to the surface.

Hilski - 25-5-2012 at 11:55

Quote: Originally posted by Mailinmypocket  
You could take say, 10mm lengths of glass tube, and dip one end very slightly in various glues. Then submerge the coated tip into a beaker of the acid... then wait to see if any of the glues or sealents fail by watching for the tubes filling with acid due to atmospheric pressure. That way you not only see if the material degrades but it also shows if it maintains a good adhesion to the surface.

I think I may give that a try. Thanks for the idea.
I'm pretty sure someone told me once that non-metallic based epoxy putty is non reactive to almost every acid, even HNO3, with the exception of concentrated H2SO4. I think I may give that stuff a try as well.

hissingnoise - 25-5-2012 at 15:51

Most strong glues are attacked by oxidising acids and they usually fail fairly quickly . . .


watson.fawkes - 25-5-2012 at 16:48

Quote: Originally posted by Hilski  
I need to affix a small glass container to the bottom (inside) of a larger glass container.
Sounds like a straightforward glassblowing job. No chemical compatibility issues with that approach.

Hilski - 25-5-2012 at 17:07

Quote:
Sounds like a straightforward glassblowing job. No chemical compatibility issues with that approach.

Yeah, that would be nice. Unfortunately, my glassblowing experience is limited to shaping small glass tubing for various purposes. What approach (glass blowing-wise) would one take to fuse a small shallow dish to the bottom of a large glass jar? Neither of the pieces are made of borosilicate glass.

Thanks

watson.fawkes - 25-5-2012 at 17:55

Quote: Originally posted by Hilski  
What approach (glass blowing-wise) would one take to fuse a small shallow dish to the bottom of a large glass jar? Neither of the pieces are made of borosilicate glass.
Melt a bead (just like a weld bead) around the circumference where the outer wall of the small dish meets the floor of the large container. The hard part is heat management so that the work doesn't crack. Preheat the whole piece, anneal with a sooty flame (cooler), and cool off slowly (insulated box). Since it's not borosilicate and you don't need to hold to mechanical tolerances, there's many an ornamental glassblower who could do the work.

Magpie - 26-5-2012 at 16:24

You might try some waterglass. But be aware that the bond may be permanent. If you try to separate the two pieces of glass they may be marred or even ruined. I really don't have any experience in doing this in an H2SO4 environment so can't say for sure what will happen.