Patent GB-656727-A (GB)
Title: Improvements in or relating to method of polymerizing an unsaturated organic compound and product thereof
IPC: C08F4/04
Filed: 1948-02-11
Abstract: Polymers and copolymers are made by polymerizing an unsaturated compound or compounds in the presence of a diazo thio-ether of the formula R-N=N-S-R1, where R is an aromatic or substituted aromatic radical and R1 an aromatic, substituted aromatic, cycloalkyl, substituted cycloalkyl, aliphatic, or substituted aliphatic radical. Specified unsaturated compounds are 1,3-butadiene, isoprene, piperylene, chloroprene, styrene, acrylonitrile, methyl acrylate, butyl acrylate, methyl methacrylate, vinyl chloride, p-chlorostyrene, p-methoxystyrene, vinyl naphthalene, acrylonitrile, methacrylonitrile, vinylidene chloride, methyl vinyl ketone, vinyl ether, vinyl carbazole, vinyl furan and vinyl pyridine.  The polymerization may be effected in bulk, solvent or aqueous emulsion, in which emulsifying agents such as partially or completely neutralized fatty acid soaps, sodium lauryl sulphate, sodium isobutyl naphthalene sulphonate or sulphated and sulphonated succinic acid esters may be used.  The diazo thio-ethers may be prepared by coupling a diazotized aromatic amine with an aromatic, cycloalkyl or aliphatic mercaptan (see Group IV (b)).  Specified diazo thio-ethers are p-methoxy phenol diazo thio-(2-naphthyl)-ether dimethyl phenyl diazo thio-(2-naphthyl)-ether, dimethyl phenyl diazo thio-(p-methoxy phenyl)-ether, p-methoxy phenyl diazo thio-(o-carboxy phenyl)-ether, p-sulpho-phenyl diazo thio-(2-naphthyl)-ether, p-sulpho-phenyl diazo thio(p-tolyl)-ether, 2-naphthyl diazo thio-(carboxy phenyl) - ether, p-chloro - phenyl diazo thio - (2-naphthyl)-ether and where appropriate the ammonium or alkali metal salts.  The diazo thioethers may be water or solvent-soluble and they may be used in conjunction with mercaptans, e.g. t-dodecyl mercaptan and potassium persulphate. Polymerization may be effected in batches or continuously at a temperature between - 10 DEG  and 60 DEG  C., and the diazo thioether may be added in portions as the polymerization proceeds.  The Specification as open to inspection under Sect. 91 comprises also fourteen further examples of polymerizing in the presence of a diazo thioether in conjunction with a mixture of mercaptans, or potassium ferricyanide and trisodium phosphate or in the presence of actinic light.  This subject-matter does not appear in the Specification as accepted.ALSO:Diazo thio-ethers of the formula R-N=N-S-R1 where R is an aromatic or substituted aromatic radical and R1 an aromatic, substituted aromatic, cycloalkyl, substituted cycloalkyl, aliphatic or substituted aliphatic radical are made by coupling, preferably in an alkaline medium a diazotized aromatic amine with a substituted or unsubstituted cycloalkyl, aromatic, or aliphatic mercaptan. Specified amines are aniline, chloroaniline, bromoaniline, toluidine, anisidine, phenetidine, 4-aminodiphenyl ether, dimethoxy aniline, nitro-aniline, methylmethoxy aniline, trimethyl aniline, dichloroaniline, xylidine, chlorotoluidine, naphthylamine, dianisidine, benzidine, dichlorobenzidine, sulphonilic acid, aminobenzoic acid, toluidine sulphonic acid, naphthylamine sulphonic acid, and benzidine disulphonic acid.  Specified mercaptans are thio-phenol, thio-cresol, chlorothio-phenol, methoxy thio-phenol, thio-salicyclic acid, thio-phenol sulphonic acid, thio-naphthol, 2-mercapto-3 naphthoic acid, thio-glycollic acid, ethyl mercaptan, butyl and t-butyl mercaptan, cyclohexyl mercaptan, mercapto benzothiazole, and octyl mercaptan.  In examples (1) p-methoxy phenyl diazo thio-(2-naphthyl) ether is made by pouring a diazotized solution of p-anisidine into a sodium hydroxide solution of thio-beta-naphthol; (2) 2-naphthyl diazo thio-(carboxy phenyl) ether by coupling in sodium hydroxide solution diazotized beta-naphthylamine and thio-salicyclic acid; (3) p-sulpho phenyl diazo thio-(p-tolyl) ether by coupling diazotized sulphanilic acid and p-thio-cresol; (4) p-methoxy phenyl diazo thio-(carboxy phenyl) ether by coupling diazotized p-anisidine with thio-salicyclic acid; (5) p-chloro phenyl diazo thio-(2-naphthyl) ether by coupling diazotized p-chloroaniline with thio-beta-naphthol; (6) dimethyl phenyl diazo thio (2-naphthyl) ether by coupling diazotized m-xylidine with thio-beta-naphthol. Other specified thioethers are dimethylphenyl diazo thio-(p-methoxy phenyl) ether, and p-sulpho-phenyl diazo thio-2-(2-naphthyl) ether.  The diazo thio-ethers are used as polymerization catalysts.