High T_g Poly(ester-co-vinyl)s with Compositional Homogeneity by Radical Ring-Opening Polymerization

The synthesis of polyesters by radical ring-opening polymerization (RROP) holds some major advantages over conventional methods such as polycondensation, such as a variety of possible reaction conditions, simple initiators, and the possibility of copolymerization with vinyl monomers. This offers a broad spectrum of potential products. The obtained functionalized poly(ester- co -vinyl)s have so far been mainly discussed for biomedical applications. However, they could also be of interest as polyolefin alternatives in the context of increasing plastic pollution. In this work, a comonomer system consisting of 2-methylene-4-phenyl-1,3-dioxolane (MPDL) and syringyl methacrylate (SM) was explored, as high glass transition temperature polymers with predetermined breaking points are required for degradation. Due to the wide difference in the reactivity of the two monomers (copolymerization parameters r MPDL = 0.004 and r SM = 5.407), the homogeneous distribution of ester moieties in the copolymer was achieved by semibatch copolymerization. The compositional homogeneity and degradation of ester units were studied by basic hydrolysis in KOH.