| Abstract
| - Star-shaped poly(vinyl ether)s with narrow molecular weight distributions were obtained frompolymer-linking reactions of living polymers with a divinyl compound based on living cationic polymerization.For example, living polymers (DPn = 50−300) of isobutyl vinyl ether (IBVE), prepared with a cationogen/EtAlCl2 at 0 °C in hexane in the presence of ethyl acetate, were allowed to react with a small amount of1,4-cyclohexanedimethanol divinyl ether (DVE-1) to give a star-shaped poly(IBVE) in quantitative yield(100%). In addition, a notable feature of this star-shaped polymer was extremely narrow molecular weightdistribution (Mw/Mn = 1.1−1.2). The structure of divinyl compounds and reaction conditions for the linkingreaction are key factors for achieving quantitative yield of star-shaped polymers. To our best knowledge,this is the first example of selective preparation of star-shaped polymers with narrow molecular weightdistribution via one-pot polymer-linking reactions, which has never been achieved in any other mechanisms.The Mw and the number of arms per molecule ranged from 6 × 104 to 30 × 104 and 9 to 44, respectively.Thermosensitive star polymers were also synthesized in quantitative yield, and the products were found toundergo sensitive phase separation and physical gelation.
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