Polyolefins represent the largest contribution to plastic production, use, and generated waste worldwide (e.g., 62% of plastics produced in the U.S. are polyethylenes and polypropylenes), yet their recycling rates are abysmally low (1-10% for various polyolefins in the U.S.). More efficient methods of recycling polyolefins have been underexplored, due to significant technological, scientific and economic challenges. Current recycling is limited by the inherent cost in and supply chain logistics of collecting, sorting and cleaning diverse plastic composition waste streams, the presence of additives, fillers and inks, and the downgrading of polymer properties during mechanical recycling. The lack of control over polymer architecture and molecular weight invariably results in recycled materials with inferior properties.
This presentation will discuss new strategies for recycling and reuse of polyolefin waste, including (i) upcycling polyolefins to durable thermoset materials and (ii) compatibilizing mixed plastic waste. Challenges which are unique to polyolefin recycling and the opportunities they present for polymer scientists will also be discussed.