Ask the Expert Question-and-Answer Archive

by Ron Joseph

November, 2005

Chemical Resistance of Aerospace Polyurethane MIL-C-83286

Q. Will polyurethane paint, such as MIL-C-83286 protect aluminum surface from Nitrous Oxide?

A. Offhand I don't know, and in all probability this information is not on the Mil-spec because concentrated nitrous oxide is not a chemical with which an aircraft might come into contact. Also, you need to be more specific regarding the exposure. Is this concentrated pure nitrous oxide (NO) or are you referring to a NO as a component of smog? Are you concerned about NO when it comes into contact with water or atmospheric moisture to form an acid? And if so, for what period of time and at what temperature?

Once you have defined the parameters you can refer to the main suppliers of MIL-C-83286, such as Sherwin-Williams, PPG, Deft Inc..etc. for an answer. If you are only concerned with NO as a component of atmospheric smog, then I do not believe that the coating is affected, but that is only my guess. After all, thousands of military aircraft fly through smog on a daily basis.

I hope this answers your question.

Best wishes,

Ron Joseph