University at Buffalo chemical engineering faculty develop paths to recycling multilayer plastic films

By Elizabeth Egan

While many single-use plastics, such as soda bottles and milk jugs, can be recycled, packaging made of flexible multilayer films, used in products such as food wrappers and medication packaging, are not currently recycled.

Multilayer films are made up of layers of different plastics and often other materials such as paper or metal. The layers are bound tightly to be kept together during the product’s life span. However, the presence of multiple-bonded polymers means these plastics can only be disposed of in landfills or incinerators.

Despite the end-of-life challenges, the benefits of multilayer plastics are crucial to many products that require the functions of different materials. For example, polyethylene is heat-sealable and a barrier to moisture and gas, while polyester and nylon are stronger materials and keep out liquid. Since they play an important role in how different products are packaged, the most viable means of managing multilayer film waste would be to recycle it.

To be able to recycle multilayer films, new methodologies are needed. University at Buffalo researchers are working to advance delamination as a recycling process to separate individual types of plastics from multilayer films, allowing them to be recycled.

This work has been presented in the 2026 REMADE Circular Economy Tech Summit & Conference, and was published recently in the journals Resources, Conservation & Recycling, ACS Sustainable Chemistry & Engineering, and Polymers.

Paschalis Alexandridis, UB Distinguished Professor in the Department of Chemical and Biological Engineering and Marina Tsianou, professor in the Department of Chemical and Biological Engineering, serve as the study’s corresponding authors. Jacob S. Licht, chemical engineering 2025 PhD graduate, is the first author and Christian M. Ferger, who graduated with his PhD in chemical engineering in 2023, is the study’s co-author.

Their work documents different pathways of inducing delamination of multilayer films and utilizes appropriate solvents to disrupt adhesion between adjacent layers or dissolve a minor component of the film.

Delamination is a single-step process that operates at atmospheric pressure and temperatures under 90 °C. The process is completed in under an hour. Solvent-based delamination has been utilized on several different commercial multilayer films.

“We designed the delamination process with simplicity in mind and a focus on recovery as solid film at high purity of all polyolefin that was initially present in the multilayer film,” said Alexandridis. “We effect delamination in a physical process that preserves targeted plastics as solid film through the recycling process, hence retaining their embodied energy.”

The UB research team found that polyethylene recovered from delamination exhibited mechanical properties comparable to commercial resins and can be utilized in commercial products of equivalent application, a highly desirable outcome for plastics recycling.

They also established that the delaminating solvent can be recovered with distillation, mitigating excessive solvent usage as well as allowing any materials dissolved in the solvent to be recovered during distillation.

Their work was supported by the U.S. Department of Energy through the REMADE Institute under Award No. DE-EE0007897 and the National Science Foundation.

“Our study facilitates the design and optimization of energy efficient and environment-friendly large-scale delamination recycling process that can unlock value from the 25 million tons of multilayer films produced annually that are currently being landfilled or incinerated following their use,” said Alexandridis. “Recovery and recycling of plastics from multilayer films allows us to continue utilizing them and benefiting from their unique properties, while reducing the environmental impact of plastic waste and incorporating recycled content into plastic products.”