Oxygen Barrier Coating Resin OB-100 (EVOH-based)

EVOH is a semicrystalline polymer where oxygen permeation is blocked by the crystalline regions and the strong hydrogen bonding between hydroxyl groups. At low relative humidity (<60% RH) the hydrogen bonds remain intact and oxygen transmission is exceptionally low (<0.5 cc/m²/day). At high humidity (>80% RH), water molecules compete with hydroxyl-hydroxyl hydrogen bonds, plasticizing the polymer, increasing chain mobility and allowing oxygen diffusion through the matrix. For applications in high-humidity environments, OB-100 coatings should be laminated or topcoated with a moisture-barrier layer to protect the EVOH from humidity-induced performance loss.