Abstract: The provision of blunt protrusions on a grounded screen of a plasma reactor in combination with a working gas diluted with a predominant quantity of an inert gas provides enhanced back corona discharge and greatly increased quantities of neutral radicals near and below the grounded screen of a plasma reactor vessel operated at near atmospheric pressure. Use of helium as the inert gas allow production of reactive species of oxygen, nitrogen or both.

Abstract: A system for treating at least one surface of a material may include a reaction vessel containing a first electrode and a second electrode separated by a gap. A power source may generate an electrical potential across the first electrode and the second electrode. A mixture of a non-reactive fluid and a reactive fluid exposed to the electrical potential may produce a back coronal plasma discharge from the second electrode to the first electrode. The reactive gas may further form a treatment material within the plasma. Depending on the reactive fluid introduced in the reaction vessel, a substrate disposed distally with respect to the second electrode may be coated with the treatment material, thereby increasing the hydrophobic character of the substrate. The treated substrate may be incorporated into a composite composition composed of a hydrophobic matrix.