| abstract |
PCT No. PCT/EP96/03441 Sec. 371 Date Jan. 27, 1998 Sec. 102(e) Date Jan. 27, 1998 PCT Filed Aug. 5, 1996 PCT Pub. No. WO97/06189 PCT Pub. Date Feb. 20, 1997A process for the preparation of halogen-free, reactive polyisobutene having a content of terminal double bonds of more than 50 mol % and an average molecular weight Mn of from 500 to 5000 dalton by the cationic polymerization of isobutene or isobutene-containing hydrocarbon mixtures in the liquid phase, wherein the polymerization is carried out at a temperature of from -30 DEG to +40 DEG C. over a heterogeneous polymerization catalyst containing at least one element acting as promoter and selected from Group IB, Group IIB, Group IIIB, Group IVB, Group VB, Group VIIB, or Group VIIIB of the Periodic Table or from Group IIA, Group IIIA, Group IVA, Group VA, or Group VIA of the Periodic Table or a number of said elements in each case in the form of an oxygen-containing compound and zirconium in the form of an oxygen-containing compound, said polymerization catalyst containing no industrially effective amounts of halogens. |