PROCESS FOR PRODUCING ISOBUTENE POLYMER

摘要

The present invention provides a process for obtaining an isobutene polymer having a specified structure in a specific solvent system under industrially favorable conditions. The present invention relates to a process for the preparation of an isobutene polymer terminated by functional groups at a temperature of from not lower than -100 DEG C to not higher than 0 DEG C from the following components as essential components: (A) a cationically polymerizable monomer containing isobutene; (B) an organic compound as an initiator/chain transfer agent represented by formula (1): <CHEM> wherein X represents a halogen atom, an RO- group or an RCOO- group (in which R represents a monovalent organic group); R<3> represents a polyvalent aromatic group or a substituted or unsubstituted polyvalent aliphatic hydrocarbon group; R<1> and R<2> may be the same or different and each represent a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group, with the proviso that when R<3> is a polyvalent aliphatic hydrocarbon group, one of R<1> and R<2> is not a hydrogen atom; and n represents an integer of from 1 to 6; (C) an aprotic solvent; and (D) a Lewis acid, wherein the component (C) exhibits a dielectric constant of from not less than 2.0 to not more than 5.5 at a temperature of 20 DEG C.