Preparation of inorganic–organic hybrid gas barrier films by atmospheric-pressure plasma-enhanced chemical vapor deposition

Abstract

Inorganic–organic hybrid gas barrier films were prepared using atmospheric-pressure plasma-enhanced chemical vapor deposition (AP-PECVD) with tetramethoxysilane (TMOS) and methyltrimethoxysilane (MeTMOS). The effect of MeTMOS content on the gas barrier properties [oxygen permeability coefficient and water vapor transmission rate (WVTR)] of the films was investigated. The oxygen permeability coefficient of the hybrid layer was low, approximately one-fourth that of polyvinylidene chloride (PVDC). The WVTR of the hybrid layer (normalized to 25 µm thickness) was of the same order as that of PVDC. The light transmittance of the hybrid gas barrier film coated on polyimide (PI) was 75.7 % at 600 nm, and the pencil hardness (750 g load) was 5B. In the flexibility tests, where the film was bent ten times around a 2 mm diameter stainless steel rod, no cracks were observed on the surface of the film. The hybrid gas barrier films exhibited excellent oxygen and water vapor barrier properties, in addition to transparency, hardness, and flexibility.