NON-TECHNICAL SUMMARY Plastic waste is a growing environmental and societal challenge, with millions of tons accumulating in landfills and oceans each year. These plastics persist for centuries, harming ecosystems and public health. This research addresses this problem by creating sustainable plastics that can naturally decompose, using plant-based materials called cellulose nanofibers. These nanoscale fibers are abundant, break down safely, and derived from the non-edible parts of plants, making them a promising alternative to current commercial plastics. However, due to limited methods to modify plant nanofibers at scale, plastics made from these materials have constrained properties and functionality, preventing their widespread use. This research tackles these limitations combining eco-friendly chemistry with artificial intelligence and machine learning (AI/ML) to develop plant nanofiber-based plastics with “programmable” properties, meaning their resistance to breakage, water barrier abilities, and adhesiveness to other surfaces, etc., can be customized for applications in electronics, packaging, and biomedical devices. The approach uses water-based chemical processes instead of harmful solvents, while AI/ML accelerates innovation by predicting how chemical changes affect material performance. This research supports national interests by reducing plastic pollution, advancing U.S. leadership in sustainable manufacturing building on domestic feedstocks, and promoting bi