How to dissove nylon but not Neoprene 1

[magnasanti]

I have Neoprene foam rubber laminated with Nylon but It is necessary to remove the nylon any thoughts on how I could achieve this?

 

[moltenmetal]

Doubtful you could do it with a selective solvent, but nylon is a polyamide and hence can be hydrolyzed by acids. Whether that will allow you to practically separate it from your foam rubber is another matter.

 

[MikeHalloran]

Some nylons, not all, will dissolve overnight in alcohol, e.g. ethanol. Neoprene should resist it.


Mike Halloran
Pembroke Pines, FL, USA

 

[chicopee]

MikeH, I think that you meant rubber will dissolve in alcohol and we have all seem this type of problem with engine carburetors in which rubber diaphragms disintegrate due to the excessive alcohol content in gasoline.

 

[MikeHalloran]

No, chicopee, I mean that:

Neoprene is generally rated 'excellent' for resistance to alcohols.

I have personally conducted room temperature solvent resistance tests of custom molded plastic items for use in specialized medical equipment. One particular part, molded of a nylon sample I got from Dynamit Nobel (surprise; a major plastic resin producer) disappeared completely overnight. The laboratory was under my control. The part was not stolen. It dissolved. I don't remember exactly which alcohol was in the jar. I think it was ethanol, because the stuff is everywhere in medical environments. Methanol is uncommon in medicine, so we had no reason to test with it. Similar items molded of other nylon resins did not show any deterioration in the same test on the same night.

So, I stand by my statement that _some_ nylons will dissolve in alcohol, and neoprene generally should not.



Mike Halloran
Pembroke Pines, FL, USA

 

[btrueblood]

"Rubber" does not dissolve in alcohol. Isoprene is natural rubber, and it (along with a lot of other rubbers like neoprene, EPR, SBR, Butyl and the fluoro-elastomers) is quite resistant to ethyl alcohol. What does break down in alcohol is nitrile rubber, which is one of the go-to elastomers for fuel systems, as it doesn't break down in gasoline or other non-polar hydrocarbons. Isoprene, neoprene, EPR, butyl - don't hold up to gasoline. Mix gas and alcohol, and you are stuck with using the fluoro-elastomers (and even then, you need to pick the right one).

 

[Compositepro]

Some nylons do dissolve in ethanol. Aggressive agitation will speed the process.

 

[btrueblood]

Again, be careful - denatured ethyl alcohol sometimes has naptha or other hydrocarbons added to it to make it un-drinkable. Neat ethanol is what you should use to avoid damaging the neoprene rubber; you may need to go to a liquor store to buy this (I'd suggest Everclear brand).

 

[chicopee]

I guess it depends on the type of rubber and type of alcohol. I do remember a case in which excessive alcohol was used in a coolant to prevent it from freezing while a bolt hole pattern was being drilled. This excessive alcohol leached out the rubber from the hose thru which the coolant was being piped. In essence the coolant turned black from the rubber.