Need help finding a certain kind of foam

[leroyjenkens]

I'm looking for some foam that can be used as an airtight seal, but it needs to be soft. Maybe a little bit firmer than memory foam, if you know how soft that is. So it needs to be closed cell foam, that's relatively soft, but I don't know what kind of foam to search for. I'd have to buy it online because I don't know of any stores that specialize in foam. I just don't know what kind of foam to look for. I don't know any of the names. Anyone have any suggestions?

 

[lisab]

Does it have to be chemically resistant? How long does it have to last? Will it be exposed to sunlight or UV?

 

[Evo]

I'm looking for some foam that can be used as an airtight seal, but it needs to be soft. Maybe a little bit firmer than memory foam, if you know how soft that is. So it needs to be closed cell foam, that's relatively soft, but I don't know what kind of foam to search for. I'd have to buy it online because I don't know of any stores that specialize in foam. I just don't know what kind of foam to look for. I don't know any of the names. Anyone have any suggestions?

What do you plan to use it for? That might help us find what you need. I use a spray foam to create seals around certain things. Hobby stores sell various types of foam in many textures and sizes. An upholsterer could sell you foam. Like I said...more info please.

 

[leroyjenkens]

Does it have to be chemically resistant? How long does it have to last? Will it be exposed to sunlight or UV?

No it doesn't have to resist chemicals and it's not going to be exposed to UV light.

What do you plan to use it for? That might help us find what you need. I use a spray foam to create seals around certain things. Hobby stores sell various types of foam in many textures and sizes. An upholsterer could sell you foam. Like I said...more info please.

It's going to be a seal for a vacuum chamber. I don't want it permanently stuck to the table, though.

I could check a hobby store. Then I could actually feel the foam to make sure it's what I want. Thanks.
I'll have to search for upholsterers.

 

[Danger]

Leroy, is there any particular reason that this has to be foam? I ask because most of the seals that I've seen in similar roles were neoprene, Teflon, etc..

 

[leroyjenkens]

Leroy, is there any particular reason that this has to be foam? I ask because most of the seals that I've seen in similar roles were neoprene, Teflon, etc..

I figured foam would provide the softness I wanted.

I have some neoprene, but it's kinda hard. It's like foam rubber. Is there a softer version of it?

 

[Danger]

Is there a softer version of it?

I don't know, but I think that the formula is reasonably alterable. There is also, of course, silicone sealant such as Imperial or DuPonte, or bathtub caulking. They're fairly soft. They're also messy as hell before they're dry, so might be more trouble than they're worth.

 

[lisab]

Neoprene is what SCUBA suits are made of. It's pretty soft, durable, and it's closed foam. Maybe a dive shop might have some they use as patches?

 

[jim hardy]

It might be worth a phonecall or email to a manufcturer. If you can reach a sales engineer they'll generally point you to a commercial otc product.

I found a few with a search...

http://www.clarkfoam.net/polyurethane_foam_products.html
http://canada.foambymail.com/polyurethane-foam.html
http://www.foamfabmn.com/polyurethane.html
http://www.generalplastics.com/?_vs...ign=General+Plastics&ex=ccfxuh-13c8k9q-dm09nf

also check your local auto parts store ... there's lots of gasket making plastic goop in tubes.

and boat supplies. Closed cell polyurethane is used for floatation because it doesn't soak up water.

 

[Q_Goest]

McMaster Carr has everything.

 

[chemisttree]

It's going to be a seal for a vacuum chamber. I don't want it permanently stuck to the table, though.

If you are going to use it for a high vacuum chamber, you will be very disappointed with foam of any kind. You will never get the pressures you need. High vacuum chambers use soft metal (zero outgassing) seals. You might get by with a solid silicone seal, though.

I wouldn't consider any kind of foamed seal in a vacuum environment.