Researchers develop easier-to-recycle multilayer plastics 

Each year, the world produces roughly 100 million tons of flexible multilayer plastic packaging — materials that keep food fresh and pharmaceuticals safe from moisture and oxygen. Yet most of these plastics are nearly impossible to recycle due to their complex, chemically incompatible layers. Michigan State University scientists have developed a new kind of plastic film that could change that.

Working with the Pacific Northwest National Laboratory, researchers from MSU’s School of Packaging and College of Engineering have created a strong, lightweight plastic that keeps products fresh while being easier to recycle or even biodegrade. The work, published in the Chemical Engineering Journal, was supported by a $1.7 million grant from the U.S. Department of Energy, or DOE.

“One of the plastics industry’s biggest challenges is making previously unrecyclable plastics recyclable,” said Muhammad Rabnawaz, MSU professor of packaging, Faculty Laureate, and director of the National Science Foundation’s Center for Plastic, Paper and Hybrid Packaging End-of-Life Solutions, or C3PS. “Our goal was to create high-performance packaging that’s also sustainable. These are high-performance materials that happen to be recyclable.”

Rethinking plastic design

Traditional multilayer packaging combines several incompatible materials — each serving a different purpose — that can’t be separated during recycling. The MSU-led team redesigned the structure so all layers belong to the same polymer family.

The new films rely primarily on polyester, the same plastic used in water bottles. They can be made with existing manufacturing equipment, offering industry a path to transition toward circular packaging without changing production lines.

The films can be recycled in two ways:

• Mechanically: They can be shredded, melted and remade without losing strength or flexibility.
• Chemically: Using a milder process, utilizing lower temperatures to break down the plastics into their base components and reused for food-grade applications — something rarely possible with conventional packaging.

The MSU polyester-based multilayer film directly addresses the challenge in plastic recycling technologies that often rely on either mechanical or chemical pathways. Mechanical recycling typically makes the most sense for clean, post-industrial streams, while chemical recycling is better suited for mixed or contaminated post-consumer waste.

This new polyester-based multilayer film is engineered to perform well in both systems, enabling high-performance packaging that can be efficiently reprocessed regardless of where it enters the waste stream. As a result, it transforms multilayer films from one of the hardest-to-recycle plastics into a fully circular, dual-recyclable platform.

The DOE funding also supported training for graduate students and postdoctoral researchers, helping prepare the next generation of scientists and engineers in sustainable materials. Mohamed Abdelwahab, the project’s lead postdoctoral fellow, said the experience was transformative for his professional growth.

This project highlights how federal support can accelerate packaging research, translating polymer science into practical, scalable and recyclable solutions that benefit manufacturing and the economy while reducing energy use.

From lab to market

The new polyester platform could extend beyond flexible films. Rabnawaz noted that the materials are compatible with existing manufacturing infrastructure.

“What’s exciting is that the innovation isn’t just in the chemistry — it’s in making circularity practical,” Rabnawaz said.

The study demonstrates how strategic DOE investment can bridge the gap between laboratory research and real-world application. By integrating chemical compatibility and recyclability into material design from the start, the team created a potential model for future sustainable packaging.

This study shows that designing for both performance and recyclability is possible and can help advance the transition toward more sustainable packaging, Rabnawaz said.

“The real impact of innovations like this will only be realized when the supporting infrastructure is in place and when virgin resin prices no longer undercut recycling,” he said. “Virgin plastic is newly manufactured plastic, created from virgin resin derived from raw materials like crude oil or natural gas. Today, virgin plastics are often cheaper than recycled alternatives, a market imbalance that suppresses adoption of advanced recycling solutions. MSU polyester platform will achieve their full environmental and economic value when waste-collection, sorting and recycling infrastructure is expanded — and when policies or pricing structures narrow the cost gap between virgin and recycled materials.”

Rabnawaz’s collaborators include, Laurent Matuana, professor, School of Packaging; Rafael Auras, professor, School of Packaging; Shiwang Cheng, associate professor, College of Engineering and Huan Lei, associate professor, College of Engineering.

The MSU School of Packaging holds the prestigious reputation of being the first, the largest and the most comprehensive packaging school in higher education. It is the only packaging Ph.D. degree offered in the United States.