GB283840A - Improvements in and relating to the manufacture of synthetic rubber - Google Patents

Abstract

283,840. I. G. Farbenindustrie Akt.- Ges. Jan. 14, 1927, [Convention date]. Emulsions, making. - Hydrocarbons suitable for the manufacture of synthetic rubber, such as butadiene, isoprene, and dimethylbutadiene, are emulsified and are then polymerized in the presence of oxygen and/or of substances yielding oxygen. The medium in which the emulsion is prepared may be an inert substantially aqueous liquid or solution or a water-containing viscous liquid, and in this connection reference is made to solutions of soaps, albuminous substances, salts of sulphonated fatty acids and of aralkyl sulphonic acids and saponin, and also to aqueous suspensions of oils. For accelerating the polymerization, it is preferred to employ an alkaline oxygen-yielding substance such as sodium perborate, potassium percarbonate or barium peroxide, but other oxygen-yielding substances also may be used with the addition, it may be, of a small amount of alkali. In one example, a mixture of isoprene and dimethylbutadiene is emulsified in water containing egg albumen and soap, and polymerization is effected in the presence of gaseous oxygen. In another example, sodium perborate is added to a mixture of isoprene, water, and sodium or potassium oleate, and the mixture is emulsified in the presence of air; polymerization is then effected at 60-70‹ C. In a further example, an emulsion of isoprene and butadiene in an aqueous solution of sodium isobutylnaphthalene sulphonate is treated with potassium percarbonate, whereafter the hydrocarbons are polymerized. Specification 14556/12, [Class 2 (iii), Dyes &c.], is referred to.