I make a thermal actuator that works with the expansion of diethyl ether at its boiling point of around 34 °C. For sealing and lubrication of the polypropylene piston and barrel, I need a lubricant that is immiscible with diethyl ether and does not react with it.
I found that diethyl ether is slightly soluble in water, and that it dissolves oils. I suppose this means that many of the everyday oil- and water-based lubricants are not fit for this application (as diethyl ether will dissolve in the lubricant)?
Any other suggestions for a lubricant that can be used here?