GB308755A - Improvements in and relating to the manufacture of synthetic rubber - Google Patents

Abstract

308,755. I. G. Farbenindustrie Akt.- Ges. March 31, 1929, [Convention date]. Addition to 283,841. Caoutchouc, synthetic.-The process for the manufacture of synthetic rubbers described in the parent Specification in which polymerization of an appropriate hydrocarbon is effected in an atmosphere of hydrogen, nitrogen or carbon dioxide, by means of an alkali metal in the presence of an organic hydroxy compound or ether, is modified by working the process in the presence of ethyl ether, diphenyl ether or an olefine oxide or peroxide. In examples, (1) 1M kg. of isoprene. 20 kg. of ethyl ether and 2 kg. of sodium wire are left to stand in a carbon dioxide atmosphere, (2) 200 kg. of isoprene and 5 kg. of diphenyl ether or 5 kg. of ethylene oxide are heated at 45‹ C. with 3 kg. of sodium wire in a nitrogen atmosphere. The Specification as open to inspection under Sect. 91 (3) (a.) describes three particular examples of carrying out the process of the parent Specification. Example (1) refers to erythrene instead of isoprene and nitrogen instead of the carbon dioxide referred to in Example (1) above. In example (2) 100 kg. of erythrene or dimethyl butadiene are polymerized in the presence of 2 kg. of ethyl cellulose and 1.5 kg. of finely divided sodium or sodium wire, in a nitrogen atmosphere at fi0‹ C. with shaking. Example (3) refers to dimethyl ether instead of the diphenyl ether referred to in Example (2) above. The polymerization may also be effected in the presence of substitution products of organic .hydroxy-compounds or ethers, or of other compounds containing ether-like combined oxygen. This subject-matter does not appear in the Specification as accepted.