| 摘要 |
<p>1,177,909. Isolating polyisoprene from hydrocarbon solutions. FARBENFABKIKEN BAYER A.G. 27 -Nov., 1968 [21 Dec., 1967], No. 56235/68. Heading C3P. Cis-1,4-polyisoprene is isolated from a catalyst-containing solution by deactivating the catalyst by adding thereto a primary or secondary diamine or a polyamine '(a compound containing 3 or more primary or secondary amino groups), followed by steam distillation. An additional deactivating agent in the form of an aliphatic alcohol having 1 to 6 carbon atoms, or a secondary aliphatic or cycloaliphatic monoamine may also be added to the catalyst-containing solution. In the examples, isoprene is polymerized in hexane using a catalyst comprising titanium tetrachloride -and aluminium triethyl. A mixture of an amine and ethanol in hexane, followed by 2,6-di-tert-butyl-4-methylphenol (stabilizer), is added to the polymerization mixture. The solid polyisoprene is then separated by precipitation with ethanol or by steam distillation. The amine used to deactivate the catalyst is one of the following, 1,2-diaminoethane, bis- (2 - aminoethyl) - amine, 1,11 - diamino - 3,6,9-triazaundecane, 1,6-diaminohexane; 1,4- diaminobutane, optionally mixed with methyl stearyl amine and/or ethanol. 2,2<SP>1</SP>-Dihydroxy- 3,3<SP>1</SP> - di-tert - butyl - 5,5<SP>1 </SP>- dimethyl diphenyl methane may be used as a stabilizer.</p> |
