Synthesis and characterization of hybrid polymers prepared by step-growth polymerization and chain-growth polymerization by olefin metathesis

The authors report the hybridization of different olefin-containing polymers, chain-growth type polymer and step-growth type polymer, by olefin cross metathesis. An equal amount of olefin-containing polyester and 1,4-polybutadiene was mixed and dissolved in dichloromethane in the presence of Grubbs catalyst at room temperature. As the reaction proceeded, the melting endothermic peak of the hybrid polymer shifted to lower temperature. Finally, the melting peak was completely disappeared in DSC thermogram. The change in specific heat corresponding to the glass transition temperature of hybrid polymer was observed between each glass transition. These results indicate that the polymer scrambling reaction finally gives random copolymer consisted of butadiene unit and oligoester unit.