Patent ID: 8853336

Claim:
A boron trifluoride-catalyst complex for polymerization of isobutene, consisting of boron trifluoride as a polymerization catalyst and a cocatalyst mixture of (A) 10 to 90% by weight of at least one monohydric primary alcohol having 1 to 20 carbon atoms and (B) 90 to 10% by weight of at least one monohydric secondary alcohol having 3 to 20 carbon atoms, where the molar ratio of boron trifluoride to the sum of all cocatalyst alcohols from (A) and (B) is 2:1 to 1:10, wherein an isobutene homopolymer formed by reacting isobutene in the presence of said boron-trifluoride catalyst complex has a fluorine content of less than 143.