With 1,124 million tons of plastic projected to be produced in 2050, consuming 20% of global oil production, the plastic industry relies heavily on nonrenewable resources for new materials. In addition to unsustainable feedstocks, only 10% of plastics are currently recycled, with 32% of waste leaking into the environment to remain there. Therefore, in the effort to create a circular plastic economy, vinyl ethers (VEs) offer an appealing alternative to address these challenges, as the polymers can be sourced from bioderived feedstocks, have a wide range of properties, and can be recycled or degraded. In my graduate research, I have worked towards the expansion and commercialization of poly(vinyl ethers) (PVEs). To improve the resource efficiency and facilitate scale-up, a water and air tolerant polymerization of VEs was developed to run at room temperature without solvent, while still retaining functional chain ends. By increasing the rates of reaction with a hydrogen bond donor, the breadth of acids capable of initiating rapid cationic polymerizations was expanded to fluorine-free anions, reducing the potential risks and extending the possibilities for photoinitiated applications. To demonstrate the versatility of PVEs, I synthesized materials ranging from tough thermoplastics with high glass transition temperatures (Tgs) to soft elastomers that recover when stretched. At the end of use, PVE plastics can be reprocessed with similar properties or oxidatively degraded to benign products.