Sciencemadness Discussion Board

Anti-Corrosion Oil Additives

Striker - 26-10-2023 at 13:09

I'm trying to formulate a lubrication blend that's chemically-compatible with polycarbonate. The blend will be based on motor oil and may also contain automatic transmission fluid (ATF) subject to my ongoing test of ATF's compatibility with PC.

I want to add a corrosion inhibitor to the blend to prevent rust beyond the protection offered by the other components. PC HATES amines and dislikes cresols, which are common additives for this purpose, so I need to find other options that will play well with both the motor oil (miscible in it if not liquid) and PC.
Any ideas or insight? I'd like to consider the options before beginning empirical testing.

This is my first post after lurking a while, so please excuse if I'm posting in the wrong place or tripped on a rule.

Elemental Phosphorus - 18-11-2023 at 09:02

Maybe calcium sulfonate might be a good option? It's commonly used as a lubricant thickener and rust preventing agent. I couldn't find compatibility data on a chart unfortunately, but it seems like it might be better, compatibility-wise than other solvent-y additives like heavy amines and cresols. Polycarbonate in general, as long as I remember, really doesn't like slightly polar solvents, I believe it can be solvent glued using MEK.

Perhaps calcium sulfonate could work as a corrosion inhibitor?

B(a)P - 18-11-2023 at 11:15

An interesting YouTube video popped up on my feed just the other day about this. You might like to watch this video.

[Edited on 18-11-2023 by B(a)P]

Striker - 27-11-2023 at 08:48

Quote: Originally posted by Elemental Phosphorus  
Maybe calcium sulfonate might be a good option? It's commonly used as a lubricant thickener and rust preventing agent. I couldn't find compatibility data on a chart unfortunately, but it seems like it might be better, compatibility-wise than other solvent-y additives like heavy amines and cresols. Polycarbonate in general, as long as I remember, really doesn't like slightly polar solvents, I believe it can be solvent glued using MEK.

Perhaps calcium sulfonate could work as a corrosion inhibitor?


Thanks for the advice. I came across Calcium Sulfonate in my quest at one point, but sulfonates are esters and I read that PC doesn't like esters. Maybe I'm misunderstanding or maybe it's not all esters? But yeah, at least it doesn't seem as bad for PC as amines et al.

Maybe I'll buy some to try since you suggest it also.

Texium - 27-11-2023 at 08:52

It might be fine. “Esters” in that context is probably referring to organic esters used as solvents, such as ethyl acetate. Sulfonate esters are very different.

Striker - 27-11-2023 at 13:46

Ah. Gotcha. Thanks.