Interpolymerization of fumaric esters and isobutylene

501,669. Interpolymers of isobutylene and fumaric esters. JOHNSON, U. W. (I. G. Farbenindustrie Akt.-Ges.) Sept. 17, 1937, No. 25282. [Class 2 (iii)] Interpolymers are prepared by polymerizing mixtures of fumaric di-esters and isobutylene in an aqueous emulsion in the presence of polymerization catalysts. Fumaric esters specified are fumaric dimethyl, diethyl, di-n-butyl di-isobutyl, dioctyl and di-(ethylene-glycol monomethylether) esters. The polymerization may be carried out in the presence of vinyl compounds such as vinyl esters, vinyl ethers, acrylic acid and their derivatives, styrene, vinyl chloride, vinyl methyl ketone and vinylcarbazole, or maleic acid esters. Soap-like substances containing a lipophilic and a hydrophilic radical are suitable as emulsifying agents, e.g. alkylnaphthalene sulphonic acids, fatty alcohol sulphonates, Turkey red oils, the hydroxyethylation products of fatty alcohols or C-alkyl phenols and the alkali salts of sulphonated mineral oils. Watersoluble organic liquids, e.g. methanol and acetone may also be employed as emulsifying agents. Catalysts specified are hydrogen peroxide, peracetic acid persulphates, percarbonates and perborates. Softening agents or fillers may be incorporated with the emulsion during or after the polymerization. The interpolymers are obtained in the form of a white milk which may be used for priming leather, for coatings, as an adhesive and for impregnating textiles. By adding electrolytes to the emulsions, the interpolymers are flocculated in a fine form, which after separation and drying, may be used as lacquer raw material or for the preparation of cable compositions. In an example, isobutylene and fumaric diethyl ester are emulsified in an aqueous solution of alpha-hydroxyoctadecane sulphonic acid sodium salt with the addition of potassium persulphate and hydrogen peroxide. The interpolymer is precipitated by hydrochloric acid ; after drying a colourless hard mass is obtained which is soluble in methylene chloride, benzene and butyl acetate. A mixture of isobutylene, fumaric diethyl ester and maleic dialkyl ester or styrene may be polymerized under the same conditions.