Patent GB-965022-A (GB)
Title: Improvements relating to vinylidene chloride copolymers
IPC: C08J7/052
Filed: 1962-06-07
Abstract: Vinylidene chloride copolymers are prepared by copolymerizing 80 to 97 weight per cent of vinylidene chloride with 3 to 20 weight per cent of other mono-olefinic material copolymerizable therewith in the presence, as polymerization modifier, of 0.1 to 20% based on the weight of monomers of at least one cyclomonoolefin. Specified cyclomonoolefins are cyclohexene, cycloheptene and cyclooctene. Preferred comonomers are alkyl acrylates and methacrylates, and acrylic, methacrylic and itaconic acids, but many others are specified including vinyl esters, vinyl and allyl ethers, vinyl ketones, vinyl aromatic hydrocarbons, unsaturated acids and the anhydrides, esters, amides and nitriles thereof, halogen substituted olefins and vinyl heterocyclic compounds.  Polymerization may be effected in the presence of catalysts, e.g. hydrogen peroxide, persalts, organic peroxides, azines and ketazines, which may be activated by reducing compounds and salts of iron, manganese or cobalt; in aqueous media in the presence of emulsifiers, e.g. salts of alkylaryl sulphonates, fatty alcohol sulphonates, paraffin oil sulphonates and long chain fatty acids, quaternary ammonium compounds, and salts of mono amides of dibasic acids.  Examples describe the copolymerization of vinylidene chloride, methyl acrylate and itaconic acid in aqueous media in the presence of sodium lauryl sulphate and (1, 5 and 6) cyclohexene, ammonium persulphate, sodium meta bisulphite and ferrous ammonium sulphate; (2) cycloheptene, ammonium persulphate, sodium toluene sulphinate and ferrous ammonium sulphate; (3) cycloheptene, hydrogen peroxide and ferrous ammonium sulphate; and (4) cyclooctene and azodiisobutyronitrile.  The copolymers may be dissolved in organic solvents e.g. toluene/tetrahydrofuran mixtures, and used to coat flexible substrates, e.g. regenerated cellulose film, paper and films of cellulose derivatives, polyesters, polyolefins and polyamides, to provide packaging material for food and cigarettes. Specifications 545,523, 593,947, 634,105 and 964,221 are referred to.ALSO:Flexible substrates may be coated with vinylidene chloride copolymers prepared by copolymerizing 80-97 weight per cent of vinylidene chloride with 3-20 weight per cent of other monoolefinic material copolymerizable therewith in the presence, as polymerization modifier, of 0,1-20% based on the weight of monomers of at least one cyclomonoolefin. Specified substrates are regenerated cellulose film, paper, and films of cellulose derivatives, polyesters, polyolefins and polyamides. The copolymers may be applied from solutions in organic solvents, e.g. toluene/tetrahydrofuran mixtures, by dipping, brushing or spraying.  Specified cyclomonoolefins are cyclohexene, cycloheptene and cyclooctene.  Preferred comonomers are alkyl acrylates and methacrylates, and acrylic, methacrylic and itaconic acids, but many others are specified including vinyl esters, vinyl and alkyl ethers, vinyl ketones, vinyl aromatic hydrocarbons, unsaturated acids and the anhydrides, esters, amides and nitriles thereof, halogen substituted olefins and vinyl heterocyclic compounds.  Examples describe the coating of regenerated cellulose film with copolymers prepared by copolymerizing vinylidene chloride, methyl acrylate and itaconic acid in the presence of (1, 5 and 6) cyclohexene, (2 and 3) cycloheptene, and (4) cyclooctene.  The films may be used for packaging food and cigarettes.  Specifications 545,523, 593,947, 634,105 and 964,221 are referred to.