Multi-Component Polymers Containing Polyisobutylene Via Multi-Mode Polymerization

Abstract

Recently, the trend in polymer research has been geared toward producing advanced materials via macromolecular engineering [1]. It is known that a desired combination of physical properties could be achieved by designing tailor made block and graft copolymers. Various methods including polycondensation reactions (using telechelic oligomers) or living polymerization techniques have been used for the synthesis of multi-component polymers. Although telechelic oligomers can be made by a wide variety of techniques, their use in block copolymerization suffer from a number of disadvantages. It is known that sequential monomer addition (SMA) technique in living ionic polymerization [2] is a convenient way to prepare block copolymers possessing well-defined and predetermined structures. In addition to well established living anionic polymerization, cationic living polymerization of isobutylene has been developed during the past few years [3–8]. Well defined block copolymers are prepared by these living systems following the common strategy of SMA [7]. It should be pointed out that there are various drawbacks which quite often retards the practical application of living systems to prepare block copolymers. These drawbacks essentially relate to limitation of the method to certain monomers and exclude monomers that polymerize by other mechanisms.