METHOD FOR PREPARING HIGHLY REACTIVE LOW-MOLECULAR POLYISOBUTYLENE Russian patent published in 2004 - IPC

FIELD: organic chemistry, chemical technology, polymers. SUBSTANCE: invention relates to method for preparing low-molecular polyisobutylene and can be used in industry for manufacturing synthetic rubber and prepared product can be used as a base for succinimide and thickening additive agent. Preparing highly reactive low-molecular polyisobutylene is carried out to isobutylene or isobutylene-containing hydrocarbon fraction the compound 1-decene as the rate regulating agent taken in the amount from 1 to 80 wt.-% to isobutylene, and BF₃ as a Friedel-Crafts reagent, and co-initiating agent taken among the group of compounds of the general formula ROH wherein R means hydrogen atom, methyl, ethyl, isopropyl, n.-butyl or phenyl radical in the mole ratio BF₃ : ROH from 1:0.01 to 1:3 and in dosing BF₃ from 0.05 to 0.5 wt. -% to isobutylene; or by polymerization of isobutylene or isobutylene-containing fraction in the presence of catalyst representing the preliminary formed catalytic complex (BF₃) x (ROH) x (1-decene) x (toluene) comprising BF3-base Friedel-Crafts catalyst and co-initiating agent taken among the group of compounds of the general formula ROH wherein R means n. -butyl, sec. -butyl, phenyl radical, 1-decene as the rate regulating agent and toluene as a solvent in the following mole ratio (BF₃) : (ROH) : (1-decene) : (toluene) = 1 : (0.01-3) : (0-50) : (10-100), respectively. If 1-decene as the rate regulating agent is not the component of indicated catalytic complex then it is added to the parent isobutylene or isobutylene-containing hydrocarbon fraction in the amount from 1 to 80 wt.-% to isobutylene. The polymerization process is carried out at temperature from -20 C to +20 C. Method provides preparing polyisobutylene with molecular mass from 650 to 3500 Da, reactivity index above 80 mole % and polydispersity coefficient M_w/M_n from 1.5 to 2.5 in the diminished consumption of catalyst. EFFECT: improved preparing method. 2 cl, 1 tbl, 11 ex