GB824287A - Oxidation of copolymers of conjugated dienes - Google Patents

Abstract

Liquid copolymers of conjugated diolefins and ethylenically unsaturated monomers copolymerizable therewith are contacted with oxygen at 20 DEG to 150 DEG C. for 1 hour to four days or until at least 0.05%, e.g. 0.05 to 8% by weight of the polymer, of oxygen has been incorporated in the polymer. Specified diolefins are butadiene, isoprene, dimethyl butadiene, piperylene and methyl pentadiene. Specified comonomers are styrene, para methyl styrene, dimethyl styrene, diethyl styrene, acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, vinyl isobutyl ether, methyl vinyl ketone and methyl isopropenyl ketone. Oxygen may be introduced into the polymer by blowing in air or oxygen through a porous thimble or distributing plate in the presence of catalysts, e.g. cobalt, lead, iron or manganese naphthenates or octoates, optionally together with peroxides, e.g. benzoyl peroxide. The polymers may be prepared by bulk polymerization in the presence of benzoyl peroxide or cumene hydroperoxide, or preferably by solution polymerization in mineral spirits, butane, benzene, xylene, naphtha or cyclohexane in the presence of sodium, isopropanol and modifiers, e.g. dioxane, methyl ethyl ethyl ether, dibutyl ether or phenetole, the catalyst being thereafter destroyed by excess isopropanol, carbon dioxide or acetic acid. The products are drying oils which may be used as enamel bases and mixed with pigments, e.g. carbon black, titanium dioxide and lead pigments, solvents, e.g. Varsol, mineral spirits, white oil, naphthas, benzene and xylene, and other drying oils, e.g. linseed oil, tung oil and soyabean oil.