GB816252A - Improvements in or relating to emulsion polymerization of unsaturated compounds - Google Patents

Abstract

Organic compounds containing the CH2=C< group are polymerized in aqueous emulsion at temperatures below 10 DEG C. in the presence of a catalyst comprising a phenylcyclohexyl hydroperoxide in which the hydroperoxy group is attached to the carbon atom in the cyclohexyl ring which is attached to the phenyl ring, an activator comprising a water-soluble heavy metal salt and sodium formaldehyde sulphoxylate, and an emulsifier comprising an alkali metal soap of an unmodified rosin, rosin acid or rosin acid containing material. Specified monomers are conjugated dienes, e.g. butadiene-1,3, isoprene, 2,3-dimethyl butadiene-1,3, chloroprene, piperylene, mixtures thereof with styrene, p-chlorostyrene, p-methoxystyrene, vinyl naphthalene, acrylic acid, acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, methyl vinyl ketone, methyl isopropenyl ketone and methyl vinyl ether; and vinyl acetate, styrene, methyl methacrylate, vinyl chloride, vinylidene chloride and vinyl pyridine. The peroxide may be phenylcyclohexyl hydroperoxide or its alkyl, alkoxy, amino, bromine or chlorine substituted derivatives, e.g. methylphenylcyclohexyl, ethylphenylcyclohexyl, n-propylphenylcyclohexyl, phenyl(methyl)cyclohexyl, phenyl(ethyl)cyclohexyl, phenyl(propyl)-cyclohexyl, tert.-butylphenylcyclohexyl, phenyl-(dimethyl)cyclohexyl, pentamethylethylphenyl-cyclohexyl, bromophenylcyclohexyl, phenyl-(bromo)cyclohexyl chlorophenylcyclohexyl, phenyl(chloro)cyclohexyl, bromochlorophenylcyclohexyl, phenyl(bromochloro)cyclohexyl, methoxyphenylcyclohexyl, ethoxyphenylcyclohexyl, phenyl(methoxy)cyclohexyl, phenyl(ethoxy)cyclohexyl, dimethylaminophenylcyclohexyl, methylethylaminophenylcyclohexyl, phenyl(dimethylamino)cyclohexyl and phenyl-(methylethylamino)cyclohexyl hydroperoxides. The rosin soaps may be derived from N wood rosin, FF wood rosin, abietic and other C20H30O2 rosin acids, neoabietic, levopimaric, dextropimaric and isodextropimaric acids, mixtures of natural rosins and fatty acids, and tall oil. The preferred heavy metal salt is ferrous sulphate, preferably associated with an alkali metal, e.g. trisodium, salt of ethylenediamine tetracetic acid. Additional emulsifiers, e.g. fatty acid soaps and sodium alkylaryl sulphonates, modifiers, e.g. primary and tertiary mercaptans such as tert.-dodecyl mercaptan, viscosity reducers, e.g. trisodium phosphate, and antifreezes, e.g. methanol, ethanol, ethylene glycol, glycerol, acetone and methyl acetate, may be present.ALSO:Phenylcyclohexyl hydroperoxides in which the hydroperoxy group is attached to the carbon atom in the cyclohexyl ring which is attached to the phenyl ring may be prepared by passing oxygen or a mixture of gases containing oxygen, e.g. air, through the corresponding phenylcyclohexanes at 50 DEG to 150 DEG C. in the presence of alkali, e.g. aqueous sodium hydroxide or anhydrous calcium hydroxide. The reaction may be initiated with ultra-violet light. The phenylcyclohexanes may be of the form <FORM:0816252/IV (b)/1> wherein R1 and R2 may represent H, X, XO, X2N, Br or Cl, where X is an alkyl radical, e.g. phenylcyclohexane, methylphenylcyclohexane, ethylphenylcyclohexane, n - propylphenylcyclohexane, phenyl(methyl)cyclohexane, phenyl(ethyl)cyclohexane, phenyl(propyl)-cyclohexane, tert. - butylphenylcyclohexane, phenyl(dimethyl)cyclohexane, pentamethylethylphenylcyclohexane, bromophenylcyclohexane, phenyl(bromo)cyclohexane, chlorophenylcyclohexane, phenyl(chloro)cyclohexane, bromochlorophenylcyclohexane, phenyl(bromochloro)cyclohexane, methoxyphenylcyclohexane, ethoxyphenylcyclohexane, phenyl(methoxy)cyclohexane, phenyl(ethoxy)cyclohexane, dimethylaminophenylcyclohexane, methylethylaminophenylcyclohexane, phenyl(dimethylamino)cyclohexane and phenyl(methylethylamino)cyclohexane.