| 摘要 |
A process for making polyethylene impervious comprises slightly degrading the surface of the polyethylene, depositing on the degraded surface one or more layers of a coating made from a copolymer of vinyl acetate and then covering the thus treated surface with one or more layers of a copolymer of vinylidene chloride. Co-monomers with the vinyl acetate may be butyl or octyl fumarate or maleate, or methyl, ethyl, butyl or 2-ethyl-hexyl acrylate; co-monomers with the vinylidene chloride may be vinyl chloride, vinyl acetate or another vinyl ester, or acrylic or maleic acid or an ester or amide thereof. Examples are given of degrading polyethylene bottles by treatment with a dichromate-sulphuric acid mixture and degrading polyethylene sheet by high frequency electrical discharges followed by coating according to the invention. |
