Hydrophobic coatings on selected polymers in an atmospheric pressure dielectric barrier discharge

We present results on the development of hydrophobic coatings on polymers in an atmospheric pressure dielectric barrier discharge (DBD). The effects of X + N-2 DBD are studied, where X refers to chlorine- and/or fluorine-containing precursors, aiming at surface modification with chemically bound halogen-bearing entities. The discharge parameters and the treatment conditions were optimized, both in terms of diminution of the oxygen level in the reactor and efficient creation of X + N-2 environments. Surface analysis and characterization were performed using x-ray photoelectron spectroscopy, contact angle measurement and scanning electron microscopy. The deposition of stable hydrophobic coatings, with a complex structure due to polymerization and cross-linking, with contributions from both halogen species, fluorine and chlorine, is demonstrated.