Oxygen permeability of novel organic–inorganic coatings: I. Effects of organic–inorganic ratio and molecular weight of the organic component

The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate coated by a thin layer (0.7–1 μm) of new hybrid organic–inorganic materials based on SiO2 and PE-PEG block copolymers, have been characterized at 35 and 50 °C. A significant decrease (25–40%) of the oxygen transfer rate has been observed for coated samples with respect to bare substrate both at 35 and 50 °C. The effects on the coating permeability of organic–inorganic ratio, molecular weight of the PE-PEG block copolymers and temperature are discussed.