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In my research we have a method of making polymer open-cell foams with high tortuosity and pore sizes on the order of 50–200 nanometers. I can make thicknesses of 100 µm to 2 mm thick (and up to 5 inch diameter disk). I am looking for some cool things to do with this material, and one idea was to try to fill it with metal and then dissolve the polymer away to leave a nanoporous metal structure.

The problem is that so far I cannot get water to penetrate inside the pores, I tried up to 4 MPa pressure and it just won’t go through (small pores and hydrophobic) but acetone will get absorbed in very quickly. My question is, could there be a way to use acetone as an electrolyte and deposit metals (copper, nickel, whatever) to fill these open-cell pores?

I haven’t taken chemistry since intro chem back in undergrad so I really don’t know much of anything about electroplating, so I will be very grateful for any help on this experiment. Thank you very much, I hope I was clear in explaining what I am trying to do.

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  • $\begingroup$ Do you know the polymer foam porosity? $\endgroup$ – Jaroslav Kotowski Jul 2 '15 at 7:14
  • $\begingroup$ What is the chemical structure of your polymer? Maybe somebody can suggest another solvent. $\endgroup$ – Burak Ulgut Jul 2 '15 at 10:43
  • $\begingroup$ Thanks for the replies. The polymer is polyetherimide or polysulfone (both can be made porous) and depending on processing parameters these can be 10-60% void (air). I tried isopropyl and it goes in the pores although it takes longer to diffuse in, maybe 5-10x slower than acetone. $\endgroup$ – Nic Jul 2 '15 at 19:57
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Electroplating might be possible, but getting good coverage of internal pores is tricky, even with aqueous electrolytes, as deposition will likely occur preferentially at the outer edge of the workpiece, leaving the internal passages lightly- or un-coated.

A more effective approach is likely electroless nickel deposition. As long as you can find a suitable acetone-soluble reducing agent, it might work out.

I would also recommend testing other solvents for their ability to permeate the polymer structure -- if you could find a protic solvent that wets it (even something like 50/50 ethanol/water!), you'd have a much better chance of success at electrodeposition proper, and also at making electroless work for you, since (I think) most electroless recipes are aqueous-based.

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