Sciencemadness Discussion Board

What material should be used as a vacuum seal?

AdamAlden - 16-2-2019 at 13:08

I need a sheet of a rubber like material to be used between two surfaces to form a vacuum seal. The surface is an acrylic cylinder and two acrylic disks on either side. So the material needs to go between the lip of the cylinder and the disks to seal it when a vacuum is applied.

Does anyone know what kind of material is best? I need to buy it as a sheet and cut it to the right size.'

Also sorry for my previous posts I've been diagnosed with schizoaffective disorder and gone on medication for almost a year and it seems to have helped me out a lot.

Ubya - 16-2-2019 at 13:22

neoprene rubber sheet should work for you

elementcollector1 - 16-2-2019 at 19:32

Silicone's another good option (get the softer stuff, obviously). Pretty sure you can buy sheets as some sort of kitchen accessory?

Twospoons - 17-2-2019 at 12:24

Neoprene is better than silicone. The gas permeability of silicone is surprisingly high. I make a product that uses silicone tube as a gas diffusion membrane. That may or may not matter in your application of course.

SWIM - 17-2-2019 at 16:32

Neoprene is what they used to use as a seal in old-style Virtis lyophilizer flasks , and high vac is the whole point with those babies so it must work well.

If you only need one open end, you might be able to bond the other end on with some monomer based adhesive instead of using a gasket. I know this can be done with plexiglass, but don't know much about acrylic.

This ought to result in a stronger vac chamber if its doable.

AdamAlden - 17-2-2019 at 17:19

Neoprene looks kind of stiff or tough but it should still make a good seal with some pressure applied. Thanks for advice guys I'll give it a try.

XeonTheMGPony - 18-2-2019 at 06:11

use a silicone based lube, Vitron is my general go to due to its fairly good chemical compatibility

Sulaiman - 18-2-2019 at 08:41

Although silicone rubbers are more porous than natural rubber or many synthetic rubbers,
it is a good choice because - it is cheap and it works.
Chemical resistance is good,
you probably will not notice the porosity unless you are going for high vacuum.

Have you calculated the force on the end disks ?
I worry sometimes when I see YT videos of folks applying vacuum to large thin acrylic disks.