The ring-opening copolymerization (ROCOP) of various epoxides with cyclic anhydrides derived from β-myrcene and isoprene, named MDA and IDA respectively, was achieved using [OSSO]-type iron(III) (1) or chromium(III) (2) catalysts in combination with bis(triphenylphosphine)iminium chloride (PPNCl). In all binary ROCOP reactions, polyesters with anhydride conversion > 99% and tunable glass-transition temperatures (Tg = from −2 to 98 °C) were obtained. The Cr(III) catalyst increased polymerization rates, while Fe(III) delivered comparable polymer properties, supporting iron as a more sustainable catalyst platform. Sequential ROCOP using two cyclic anhydrides, for example MDA followed by phthalic anhydride (PA), afforded multiblock copolymers with > 95% overall conversion.Extending this chemistry to one-pot epoxide/anhydride/CO2 terpolymerizations enabled a switch from polyester to polycarbonate formation, with up to 82% of the consumed epoxide incorporated as carbonate linkages at low catalyst loading (0.10 mol%). Nuclear Magnetic Resonance (NMR) spectroscopy analyses indicated minimal polyether formation and controlled block architectures, highlighting the Fe(III) catalyst as a selective and versatile system for sustainable, renewable polymers.
Sustainable polyesters via ROCOP of bio-based epoxides with cyclic anhydrides catalyzed by [OSSO]-type Chromium(III) and Iron(III) complexes
Niknam F.;Lamparelli D. H.;D'Amato A.;Speranza V.;Aliberti F.;Pantani R.;Buonerba A.;Capacchione C.
2026
Abstract
The ring-opening copolymerization (ROCOP) of various epoxides with cyclic anhydrides derived from β-myrcene and isoprene, named MDA and IDA respectively, was achieved using [OSSO]-type iron(III) (1) or chromium(III) (2) catalysts in combination with bis(triphenylphosphine)iminium chloride (PPNCl). In all binary ROCOP reactions, polyesters with anhydride conversion > 99% and tunable glass-transition temperatures (Tg = from −2 to 98 °C) were obtained. The Cr(III) catalyst increased polymerization rates, while Fe(III) delivered comparable polymer properties, supporting iron as a more sustainable catalyst platform. Sequential ROCOP using two cyclic anhydrides, for example MDA followed by phthalic anhydride (PA), afforded multiblock copolymers with > 95% overall conversion.Extending this chemistry to one-pot epoxide/anhydride/CO2 terpolymerizations enabled a switch from polyester to polycarbonate formation, with up to 82% of the consumed epoxide incorporated as carbonate linkages at low catalyst loading (0.10 mol%). Nuclear Magnetic Resonance (NMR) spectroscopy analyses indicated minimal polyether formation and controlled block architectures, highlighting the Fe(III) catalyst as a selective and versatile system for sustainable, renewable polymers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


