SBIR Phase II: Expanding the Sustainability of Bio-plastics and PLA by Postponing End-of-Life through the use of Reactive Extrusion Chemistries

This Small Business Innovation Research (SBIR) Phase II project will develop robust manufacturing methods to commercialize novel biobased plastics made from scrap PLA resins, resulting in a new method to effectively address end-of-life management of bioplastics, specifically polylactic acid (PLA). PLA is the industry leading bioplastic as it is compostable and made from corn. However, many PLA-based products manufactured today are land filled or incinerated at their end of life. Despite being compostable, industrial composting infrastructure for PLA and other bioplastics in the United States is very limited. Under this work, a commercial scale reactive extrusion process will be developed and optimized for the robust production of hyperbranched PLA polymers from scrap PLA. Phase I research verified that hyperbranching dramatically improves the melt strength and mechanical properties of scrap PLA. These benefits give hyperbranched PLA properties that meet or exceed those of virgin PLA. The process technology being developed will overcome the significant variability in scrap PLA feedstocks, allowing for production of resin with uniform product quality. The reactive extrusion process to impart hyperbranching is cost-effective and scalable. This process will enable a viable business to sell recycled PLA resin as a value-added material intended for durable goods applications. The broader impact/commercial potential of this project is the development and commercialization of an important, novel, and cost effective way to meet the pressing need of making plastics more sustainable by adding value to the most broadly used bioplastic, PLA. Creating improved PLA resins from lower cost feedstock will ultimately expand commercial applications for PLA and create a new market for scrap PLA. The current U.S. market for PLA is approximately 300 million pounds and growing at approximately 15% annually. Commercial plastic processors and compounders using PLA will be able to replace or supplement use of virgin PLA with recycled PLA by using this technology. Additionally, by providing a commercially attractive method to recycle PLA, this new process will effectively incentivize recyclers to remove PLA from their waste sources. Penetration of PLA into durable goods markets has been slow due to the higher price of PLA resin. By using hyperbranched, recycled PLA as a feedstock that originates from packaging or consumable products, the materials costs for durable products can be significantly reduced. Recycling PLA by hyperbranching offers a way to significantly extend the end of life and help enable PLA achieve its full potential as a sustainable, resource renewable bioplastic.