Pre‐Rate‐Determining Selectivity in the Terpolymerization of Epoxides, Cyclic Anhydrides, and CO₂: A One‐Step Route to Diblock Copolymers

Abstract

Catching a second wind: In kinetic resolution polymerization, one monomer is consumed faster than the other, which creates diblock copolymers that only slowly approach 100 % conversion and contain tapering. In the title reaction, the opposite is true: the first block forms cleanly, followed by a second block that has an even higher rate of polymerization. This unique reaction allows for the programmed self‐assembly of diblock polymers that display little tapering.

Ring-opening copolymerization (ROCOP): synthesis and properties of polyesters and polycarbonates

“…28 In 2008, Coates and co-workers reported that the terpolymerizations of diglycolic anhydride (DGA), CO 2 and cyclohexene oxide (CHO) using catalyst 4b (X = OAc). 29 Detailed in situ ATR-IR spectroscopic analysis revealed that epoxide-anhydride ROCOP occurred first, and, only once the anhydride was nearly completely consumed, did epoxide-CO 2 ROCOP occur. This was surprising because when conducted independently the epoxide-CO 2 copolymerization occurs significantly faster than epoxide-anhydride copolymerization.…”

Direct Carboxylation of Zincocene Cp*2Zn

“…[7] In remarkable contrast, insertion reactions into Zn-C bonds are less favored and typically require transitionmetal complexes of electron-rich, late transition metals (Ni, Pd) as effective transmetalation catalyst.…”

Combining Sustainable Polymerization Routes for the Preparation of Polyesters, Polycarbonates, and Copolymers

“…As described in Figure 1, PE and PC can also be obtained by the ring-opening copolymerizartion (ROCOP) of epoxides and anhydrides/carbon dioxide (15,16). Thus, the perfectly alternating copolymerization of epoxides with cyclic anhydrides affords polyesters (17)(18)(19), whereas the perfectly alternating copolymerization of epoxides with carbon dioxide affords polycarbonates (20)(21)(22)(23)(24)(25)(26).…”

“…Given the success of the ROCOP and ROP routes to polyesters and polycarbonates, research has focussed on combining these two different methodologies to extend the scope of synthetic polymers and enable the synthesis of block copolymers such as poly(ester-co-carbonates) (16,(36)(37)(38)(39)(40)(41). Thus, by combing two ROP processes, Romain et al reported a sequential 'one-pot' synthesis, using a single catalyst, to prepare poly(trimethylene carbonate-co-lactides) featuring a heterotactic PLA block (36).…”