Towards Roll-to-Roll Deposition of High Quality Moisture Barrier Films on Polymers by Atmospheric Pressure Plasma Assisted Process
Abstract
An atmospheric pressure dielectric barrier discharge (DBD) was applied for the deposition of silica-like moisture barrier films on polyethylene 2,6 naphthalate foil. The diffuse plasma was sustained between two cylindrical drum electrodes in N2/O2/Ar gas flow with the addition of tetraethyl orthosilicate. The chemical composition, morphology and water vapour transmission rate of the moisture permeation barrier layers were studied as a function of the dynamic deposition rate and substrate temperature. It was demonstrated that dense silica-like layers of 100 nm thick with a good permeation barrier of ≈1.8 × 10−3 g · m−2 · day (at 40 °C, 90% RH), corresponding to three orders of magnitude barrier improvement with respect to the pristine polymer, can be deposited in an atmospheric pressure process.




