Steam corrosion of glass under polymer thin films

Polymer films averaging 600 A in thickness were deposited on the outer surfaces of glass bottles to increase the lubricity and scratch resistance of the glass. The bottles were autoclaved in steam at 3 atm absolute pressure. Direct pull tests and in‐depth XPS profiles were made to learn how adhesion and the polymer–glass interface changed with autoclaving time. It was found that sodium was depleted from the surface region under the polymer coating. The sodium depletion zone increased linearly with autoclaving time. Sodium was also leached from the uncoated surface, but after 30 min of leaching the sodium depletion depth remained essentially constant. The organic film continued to adhere well independently of autoclaving time.