Work

Contamination tolerant poly(ethylene terephthalate) composites from recycled feedstocks and cellulosic waste

Year: 2026

Type: article

Abstract: Poly(ethylene terephthalate) is one of the most recycled plastics, but recycling is often limited by material degradation and the cost of removing contaminants from mixed waste streams. Cellulose-rich materials are frequently co-generated with poly(ethylene terephthalate) waste and are commonly treated as impurities, reducing recycling efficiency. Here, we show that cellulose-rich waste materials can be incorporated into recycled poly(ethylene terephthalate) to produce composites with useful mechanical properties when degradation during processing is controlled. Three recycled poly(ethylene terephthalate) feedstocks were processed with ten weight percent cellulose-rich waste materials with and without removal of degradation by-products. Cellulosic materials degrade rapidly at processing temperatures, while the removal of degradation by-products improves material quality. A feedstock containing titanium dioxide exhibits the least degradation, fewer internal defects, and superior mechanical property retention. These results show that minimizing cellulose degradation is critical for contamination-tolerant recycling and can enable utilization of heterogeneous, hard-to-separate waste streams while reducing reliance on extensive feedstock purification. Waste cellulose can be incorporated into recycled polyester with substantial retention of material properties when degradation is controlled, according to a study comparing three recycled polyester waste streams processed with cellulose fibers.

Source: Communications Sustainability

DOI: 10.1038/s44458-026-00173-0