Synthesis of hyperbranched polymers via a facile self-condensing vinyl polymerization system – Glycidyl methacrylate/Cp 2TiCl 2/Zn

Abstract

A facile self-condensing vinyl polymerization (SCVP) system, the combination of glycidyl methacrylate, Cp 2TiCl 2 and Zn, has been firstly used to prepare novel hyperbranched polymers, consisting of vinyl polymers as the backbone, and cyclic ester polymers (poly(ɛ-caprolactone) or poly( l-lactide)) as the side chains. The polymerizations are initiated by the epoxide radical ring-opening catalyzed by Cp 2Ti(III)Cl which is generated in situ via the reaction of Cp 2TiCl 2 with Zn. The key to success is that the polymerizations can proceed concurrently via two dissimilar chemistries possessing the opposite active initiating species, including ring-opening polymerization (ROP) and controlled/living radical polymerization (CRP). We have demonstrated that this facile one-step polymerization technique can be applied successfully to prepare highly branched polymers with a multiplicity of end reactive functionalities including Ti alkoxide, hydroxyl and vinyl functional groups.