Oxygen permeability of novel organic–inorganic coatings: II. Modification of the organic component with a hydrogen-bond forming polymer

The oxygen permeability of composite materials, consisting of a LDPE substrate coated with a thin layer (0.7–1 μm) of new hybrid organic/inorganic materials based on SiO2 and PE-PEG block copolymers, has been characterized at 35 and 50 °C. The effect of adding a second organic component capable to form hydrogen bonds, namely either poly(4-hydroxystyrene) (PHS) or malic acid, has been studied. While the addition of PHS leads to a further significant decrease (50–70%) of the oxygen permeability both at 35 and 50 °C, on the contrary, the addition of malic acid leads to poorer barrier properties. A slight decrease of the permeability was obtained after plasma treatment of the LDPE surface.