Plasma polymer coatings were deposited from perÑuoro-1,3-dimethylcyclohexane (PFDMCH) and their composition and surface properties studied by XPS, grazing-angle Fourier transform infrared spectroscopy and contact angle measurements as a function of time after fabrication as they were stored under ambient conditions for more than 2 years. The spontaneous ambient oxidation of PFDMCH plasma polymers was found to be a multi-step process. The rapid initial oxygen uptake, assigned to reaction between carbon-centred radicals incorporated into the coating during deposition and in-di †using atmospheric was similar to that of plasma polymers deposited from O 2 , hydrocarbon-based monomers (alkanes, alkylamines, alcohols), suggesting that the density of radicals incorporated during deposition was similar. Subsequently, however, the extent of oxidation was much lower for PFDMCH coatings. This can be attributed to the lack of availability of hydrogen abstraction reactions, which are important for radical propagation in hydrocarbon-based plasma polymers. While XPS recorded a continuous incorporation of oxygen for more than 2 years, the air/water contact angles decreased only during the Ðrst 2 months and on further storage remained stable. There appeared to be only a small extent of surface restructuring as assessed from the small depth variations of compositions. The surface was enriched in groups at all times.