Procédé chimique de préparation d'époxydes

摘要

Diene polymers are epoxidized by treatment with an organic hydroperoxide and, as catalyst, a compound from the group consisting of peracid forming and hydroxylation catalysts. Specified polymers are liquid or solid polybutadiene polyisoprene and ethylene-propylenecyclopentadiene terpolymers. Specified hydroperoxides include cumene hydroperoxide, isobutane hydroperoxide, t-butyl hydroperoxide and ethyl benzene hydroperoxide. The preferred catalysts are compounds of molybdenum, vanadium, tungsten and selenium e.g., molybdenum disulphide or naphthenate, tungstic acid, vanadium pentoxide or selenium dioxide. A solvent is desirable, hydrocarbons and their oxygenated derivatives being specified, while t-butanol is preferred.ALSO:An olefinic material containing at least 31 carbon atoms is epoxidized by treatment with an organic hydroperoxide and, as catalyst, a compound from the group consisting of per-acid forming and hydroxylation catalysts. Specified olefinic material is linseed oil, olive oil, cottonseed oil, tall oil glycerides, castor oil, corn oil, and butyl-polyglycol esters of unsaturated fatty acids, while the hydroperoxides may be those of formula ROOH, where R is an aralkyl, aralkenyl, hydroxyaralkyl, hydroxyalkyl, cycloalkyl, cycloalkenyl, hydroxycycloalkyl, and alkyl groups having three to twenty carbon atoms, the preferred being those from cumene, ethylbenzene and isobutane. The epoxidation catalysts include compounds of Ti, V, Cb, Cr, Se, Zr, Nb, Mo, Te, Ta, W, Re and U, those of W, Mo, V and Se being preferred-specified are Mo2O3, MoO2, MoO3, molybdic acid, the molybdenum chlorides and oxychlorides, molybdenum fluoride, phosphate and sulphide, phosphomolybdic acid and its sodium and potassium salts. An inert solvent may be present. In an example, 3.6 grams of 91% cumene hydroperoxide, 0.07 gm. molybdenum naphthenate solution (containing 5% Mo) and 11.4 grm. linseed oil are reacted at atmospheric pressure for 3 hours at 90 DEG C., when 92.8% of the peroxide is converted and epoxidized linseed oil produced. Organic hydroperoxides are prepared by reacting oxygen-containing gas with an aralkyl hydrocarbon or an alkyl hydrocarbon in the presence of an oxidation initiator. Specified hydrocarbons are ethyl-benzene, cumene or isobutane. Unreacted hydrocarbon may be recycled and the alcohol by-product alpha-phenyl-ethanol, cumyl alcohol and t.-butyl alcohol respectively used as such or converted to more useful by-products. Thus, alpha-phenyl-ethanol may be dehydrated to styrene, dehydrogenated to acetophenone, or hydrogenated to ethyl benzene which may then be converted to its hydroperoxide and used for the epoxidization. Similarly the cumyl alcohol may be converted to cumene and hence to cumene hydroperoxido or the cumene alcohol may be converted to alpha-methyl styrene, and the t.-butanol to 1-butane and then by hydrogenation to isobutane.