Patent GB-686855-A (GB)
Title: Improvements in or relating to the polymerization of organic compounds in aqueous emulsion
IPC: C08F4/32
Filed: 1950-06-05
Abstract: In redox emulsion polymerization the oxidizing component comprises an arylcyclohexane hydroperoxide of the formula <FORM:0686855/IV (a)/1> where Ar is an aryl nucleus, R is alkyl, aryl, aralkyl, halogen, alkoxy or aryloxy, n is an integer not greater than 4 and the sum of the carbon atoms in Rn-Aris not greater than 16, R1 is hydrogen, alkyl, aryl, aryloxy, alkoxy or tetramethylene for two adjacent R1, and the number of R1 groups other than hydrogen is not greater than 4 and the sum of the carbon atoms in the R1 group is not greater than 10, e.g. 1 - phenyl - 1 - hydroperoxy - cyclohexane, [1 - (1 - naphthyl) - 1 - hydroperoxycyclohexane], the corresponding b -naphthyl compound, [1 - (4 - methoxyphenyl) - 1 - hydroperoxycyclohexane], the corresponding 4-phenoxyphenyl and 4-chlorophenyl compounds, 1-phenyl-1-hydroperoxy- and 2-phenyl-2-hydroperoxy - decahydronaphthalenes.  The hydroperoxide may be added to the aqueous medium as an alkali metal salt.  The activating-reducing component may be a single compound of the formula H2N(CH2CHXNH)m(CH2CHX)nNH2 where X is hydrogen or methyl, m is 0 to 8, n is 0 or 1 is 1 when m is greater than 0, e.g. hydrazine, ethylenediamine, diethylenetriamine, ethylene - methylethylene - triamine and tetraethylenepentamine, but 2,2-dipyridyl, p,p1 - tetramethyldiaminodiphenylmethane, o-phenanthroline, acetoacetanilide, dimethylaniline, alanine, morpholine and ethylmorpholine may also be used; or a mixture comprising a compound of iron, manganese, copper, vanadium or cobalt, e.g. iron pyrophosphate, derived from ferrous sulphate or nitrate or ferric sulphate and sodium or potassium pyrophosphate; and glucose, levulose, sorbose or invert sugar.  The process is particularly advantageous at polymerization temperatures below 10 DEG  C. and may be applied to the production of polymers and copolymers of 1,3-butadiene, 2,3-dimethyl-, 3-furyl-, 3-methoxy-, 2-chloro-, 2-bromo- and 2-chloro-3-methyl-1,3-butadienes, isoprene and piperylene; styrene, alkyl styrenes, p-chloro-, p-methoxy- and a -methyl-styrenes and vinyl naphthalene; acrylic and methacrylic acids, methyl and ethyl acrylates and methacrylates, methyl a -chloroacrylate, butyl methacrylate, methyl ethacrylate, acrylonitrile, methacrylonitrile and methacrylamide; methyl vinyl ketone and methyl isopropenyl ketone; methyl vinyl ether; vinylethinyl alkyl carbinols; vinyl acetate and chloride; vinyl furane and vinyl carbazole; vinyl acetylene.  The production of butadiene (65 to 90)-styrene (35 to 10)-copolymers is examplified. Emulsifying agents specified are potassium laurate, oleate, and rosinate, salts of alkyl aromatic sulphonic acids and of alkyl sulphates.  The emulsion may contain mercaptan modifiers, e.g. tert-C12, C14 and C16 mercaptans, anti-freeze agents, e.g. methyl alcohol, ethylene glycol, glycerine and erythritol and potassium chloride and hydroxide.  The pH may range from 9.0 to 11.8.  The processes may be carried out batchwise, semi-continuously or continuously, preferably under pressure to maintain the monomers in the liquid phase.  The oxidant and activator solutions may be added intermittently or continuously.ALSO:Arylcyclohexane hydroperoxides of the formula <FORM:0686855/IV (b)/1> where Ar is an aryl nucleus, R is alkyl, aryl, aralkyl, halogen, alkoxy or aryloxy, n is an integer not greater than 4 and the sum of the carbon atoms is Rn-Ar-is not greater than 16, R1 is hydrogen, alkyl, aryl, aryloxy, alkoxy or tetramethylene for two adjacent R1, and the number of R1 groups other than hydrogen is not greater than 4 and the sum of the carbon atoms in the R1 groups is not greater than 10, are made by introducing oxygen into the corresponding aryl-cyclohexane at a controlled rate for one to ten hours at a temperature of 50 DEG  to 160 DEG  C.  In example 1 phenylcyclohexane is oxidized at 125 DEG  C., using the potassium salt of diisopropyl hydroperoxide as catalyst.