Ring-opening polymerization is an essential form of chain-growth polymerization that facilitates precise control over the polymerization process. Our research delved into the realm of redox- switchable catalysis and its application in synthesizing polyesters, ethers, and carbonates through ring-opening polymerization. To broaden the range of available monomers, we also explored the ring-opening polymerization of aromatic N-carboxyanhydrides with six-membered rings, resulting in the creation of aromatic polyamides. Leveraging the potential of biodegradable polymers crafted from ring-opening polymerizations, we investigated how the stereocomplexation of block copolymers could enhance the shear viscosities of the polymer solutions in brine.