Aliphatic polyesters have attracted significant attention as renewable, recyclable, and degradable alternatives to fossil fuel-derived plastics. Yet industrial condensation polymerizations are energy intensive and afford poor molecular weight control, while chain-growth polymerizations of lactones and lactide are constrained by limited functional diversity. The ring-opening copolymerization of epoxides and cyclic anhydrides affords aliphatic and semi-aromatic polyesters with controlled molecular weight, low dispersity, and atom economy. By making use of commercially available, bio-renewable, and readily synthesized monomers, epoxide/cyclic anhydride ring-opening copolymerization accesses structurally and functionally diverse polyesters with tunable thermomechanical properties. Advances in catalytic methods have accelerated ring-opening copolymerization rates and improved control over monomer enchainment. Yet the predominant Lewis acid catalyst/nucleophilic cocatalyst systems require high loadings and are prone to transesterification and epimerization side reactions that degrade the polyester backbone. We have developed a bifunctional aminocyclopropenium aluminum salen catalyst that maintains excellent activity under formerly unproductive conditions, operating at loadings as low as 0.025 mol%. While previously reported bifunctional systems require extended linear syntheses, a modular approach enables facile catalyst optimization. Covalently tethering the Lewis acidic aluminum salen and aminocyclopropenium cocatalyst suppresses deleterious side reactions and prevents inhibition by protic species in reversible deactivation chain transfer copolymerizations. Applying the bifunctional catalyst to terpolymerizations of propylene oxide, vanillin glycidyl ether, and phthalic anhydride provides control over polyester architecture via relative rates of comonomer incorporation. Reacting the pre-polymers’ pendant aldehyde units with a diamine cross-linker affords covalent adaptive networks with dynamic imine linkages. These polyester networks exhibit robust thermoset properties at service temperatures; at elevated temperatures, their dynamic mechanical behavior depends on cross-link distribution. Multiple cycles of mechanical grinding and thermal reprocessing produce homogeneous materials that quantitatively recover the tensile properties and cross-linking densities of the pristine networks to enable extended use lifetimes. Alternatively, the polyester dynamic imine networks may be dissociated to pre-polymer or hydrolytically degraded at end-of-use.