Sidmadra - 5-8-2018 at 22:27
I have a wet mixer that has some exposed plastic parts that are definitely not resistant to common solvents like acetone, as it is not intended for
chemistry purposes. I'm looking for some sort of spray coating that would cure on the surface and resist most solvents (at RT). These parts won't be
heated or used with strong acids or anything like that. Just in contact with simple organic solvents.
I believe I found some silicone sprays that cures after you spray it on, but I am not sure about the chemical compatibility of silicone gel, even with
many room temperature solvents (namely Hexane, Acetone, Alcohols, and so on). I also considered just spraying on a PTFE spray, however I'd be
concerned about solvents washing it off the surface as it would not be cured.
Vanry - 6-8-2018 at 02:18
hi !
Use silicone caulk maybe ? I'm not certain it would be all-solvent-proof but you might give it a try.
CouchHatter - 6-8-2018 at 05:01
As it will be rotating hundreds or thousands of times in the presence of solvents, i would be concerned about anything i applied coming right off with
little use. Automotive clear coat spray comes to mind, as well as a concrete sealer.
However, I would use a 2-part epoxy and brush it on. Like i said, due to the mechanically accelerated exposure to solvents, I would not imagine many
other solutions holding up over time. At that point contamination could become an issue.
Sidmadra - 6-8-2018 at 09:37
Fortunately the plastic components aren't going to be under any sort of mechanical friction. The actual grinding/mixing components are steel, the
plastic parts serve more to hold the rotating body together.
I may just get a spray-gun like the ones used for paint and spray on a pre-mixed polymer mixture of some sort that will be crosslinked and solvent
resistant after hardening. I'd just need to work quick so it doesn't harden in the gun, which I don't think will be too much of a problem. Cheap spray
guns can be had for like $14 in a worst case scenario.
weilawei - 6-8-2018 at 13:39
I spend a lot of time working with silicone (specifically polydimethylsiloxane and derivatives). It's soluble in at least acetone, MEK, and heptane
from experience. E.g., silicone spray is acetone, heptane, and PDMS (the brand I use anyway). MEK is also quite a good solvent.
Try this paper.