Chiff and Fipple Forums

cut

Let me know if this works well for you.
I don't treat my polymer flutes with anything except for the occasional warm water rinse.
With polymer you really don't have the issues that you have with wood that requires oiling and special care to enhance the tone or avoid cracking.
The main thing on a polymer instrument is don't leave it in direct sunlight (photolysis is a Bad Thing), and don't leave it in the trunk of your car if it is 115 degrees outside. Basically the flute is safe in any environment in which you are comfortable.
--James
http://www.flutesite.com

PVC coats nicely with polyurethane. It will help keep the material clean. Don't get any of it in the embouchure hole though.