A thermoplastic container or packaging material is given low oxygen
permeability by coating with a crosslinked acrylate layer and a layer of
oxygen barrier material deposited over the acrylate layer. Another
acrylate layer may be deposited over the oxygen barrier. The oxygen
barrier is selected from the group consisting of silicon oxide, aluminum
oxide and metal. The acrylate layer may be formed from a
photopolymerizable polyfunctional acrylate that is sufficiently low
viscosity to be sprayed on the substrate or applied by dipping.
Alternatively, the acrylate layer is a polymerization product of an
acrylate monomer which is evaporated in a vacuum, condensed on the
substrate and polymerized by irradiation by ultraviolet or an electron
beam. The surface of the thermoplastic substrate is prepared for
deposition of the acrylate by either flame treating the surface of the
substrate to heat it above its melting point without deforming the
substrate to thereby smooth the surface, or by plasma treating the surface
for enhancing adhesion of the acrylate. Chilling the substrate enhances
deposition efficiency.