Hi,

 

Does anyone know if it is possible and if so how to go about making a metal or plastic (durable material) semi permeable? I may be using the incorrect terminology but basically i need to know if it is possible to change a material to enable it to allow air to pass through however not liquids.

 

One way I thought you could do this was by inserting lots and lots of minute holes in the metal, holes big enough to allow air particles to pass through but not liquids.

 

Another way would be to use a material that has these properties anyway?

 

Does anyone know of such a material?

 

Any help would be appreciated

 

Thanks!

Like a 'breathable' waterproof jacket?

yes kind of. But needs to let more air flow through

Please explain exactly what you are planning to do, then we might be able to give you a useful answer. "liquid" is a very broad term - are we talking water, heavy oil, pressurized gas, molten metal?

well yes water , and any spilt drinks etc..

i'm not sure you're going to get a large air flow through something that won't let liquid pass.

if you throw a cup of water at a bed sheet while it's hanging up you won't get much out the other side, but you want something that will react on the molecular level

 

what application is this for?

how much air needs to pass through it?

Basically as much air as possible im going to be using it as a cabinet for some laptops which will be running and need to be kept away and it will be in the range of spilt drinks etc. !! But also needs to be quiet i know this is asking for a lot but lots of fans would be too loud and take up power etc..

 

So needs to let as much air as possible through and minimal amounts of substances such as water etc..

 

Cheers

Well you don't need it to be really waterproof to stop drinks and stuff, something like a sheet would work fine. Other than that I would suggest something like what tents are made of....

You could coat a porous material in a substance that repels water (Hydrophobic). Because the coating would repel the water, it would stop it passing through the holes.

so the air is for cooling?

you should have said.

there's a number of ways you can make a cabinet to dissapate heat without letting liquids through.

a well designed heat sink ought to do it, but if you're really concerned, you can purchase a coolant system.

 

you can get peltier devices to bolt onto the CPU, they move 70W of heat (silently), a laptop shouldn't put out more than that. i've seen them for about $12 aus.