| 摘要 |
<p>A coating composition for regenerated cellulose film comprises copolymers made from 35-96.5 per cent vinylidene chloride, 0.5-2.5 per cent itaconic acid, and 3-40 per cent of one or more of the following compounds: acrylonitrile, alkyl esters of acrylic and methacrylic acids having from 1 to 18 carbon atoms in the alkyl group, e.g. phenyl methacrylate, cyclohexyl methacrylate, p-cyclohexyl phenyl methacrylate, methacrylonitrile, methyl vinyl ketone, and vinyl chloride. Copolymerization may be carried out by any known method. It may be performed in aqueous media with a catalyst, e.g. ammonium persulphate, an activator, e.g. sodium metabisulphite, and any emulsifying and/or dispersing agent, e.g. sulphated methyl oleate, sodium lauryl sulphate, and sodium naphthalene sulphonate condensed with formaldehyde. Alternatively the copolymer may be prepared in bulk, or in organic solvent media. Mercaptans such as ethyl mercaptan, lauryl mercaptan, and tertiary dodecyl mercaptan may be used to modify the copolymer. The coating of base film of regenerated cellulose with the copolymer to provide a moisture-proof, heatsealable material may be effected either from aqueous emulsion, or from solution in an organic solvent, e.g. 1,3-dioxalane, dioxane and cyclohexanone.</p> |
