SBIR Phase II: Efficient and Effective Recycling of Post-Consumer Plastics for High-Value Applications

This Small Business Innovation Research (SBIR) Phase II project will demonstrate the first commercial-scale processing of post-consumer plastic materials for high value applications using an innovative approach known as continuous mechanochemical compatibilization (CMC). In 2010, only 8% of the 230 million tons of plastic waste generated was recovered for recycling. A majority of the remaining plastic was directed to solid waste streams or landfills, resulting in poor use of non-renewable resources and contributing to environmental contamination. This effort will focus on the use of CMC to recycle materials without the need for extensive cleaning or sorting, thereby reducing processing steps, and making the use of these materials more cost-competitive with virgin resins. In addition to the environmental benefits, a successful Phase II proposal will also result in significant economic implications. It has been found that processing recycled materials alone creates nine jobs for every 15,000 tons of recovered materials. Furthermore, the increased availability of recycled materials would spur industrial adoption, leading to an increase in green jobs. Commercial feasibility will be demonstrated by manufacturing several customer specific post-consumer polymer blends via the CMC process. This process uses a standard piece of industry equipment, the twin-screw extruder, but in an innovative arrangement. The equipment configuration cools the mixture below the plastic's melting and/or glass transition temperature, allowing for unique chemistry to occur between polymers and/or fillers. Due to this chemistry, materials that either could not be recycled or which resulted in poor physical properties, can be redirected back to high value-applications. For this Phase II project, three post-consumer blends will be investigated. In order to cost-effectively manufacture these materials, this effort will focus on the study and optimization of the CMC process by researching several key processing parameters. These include chiller sizing and coolant flow, and screw configuration and design for CMC. At the close of Phase II, the goal is to have developed proven processes for production of recycled plastic pellets at a much lower price, while at the same time retaining important physical properties.