Flexible plastics—such as snack wrappers and microwaveable containers—are an affordable and essential part of our daily lives, but their very flexibility makes them highly resistant to traditional mechanical recycling. As a result, these packaging materials predominantly end up in landfills, incinerators, or as environmental litter. However, according to reports published in early March 2026 on the scientific portal Phys.org and the University at Buffalo (UB) official website, an American research team has achieved a major breakthrough: a new solvent purification process capable of non-destructively recovering the base materials of flexible plastics.
The modern food and retail industries rely heavily on flexible packaging. The root of the recycling problem lies in the fact that the most commonly used types—polypropylene (PP) and polyethylene (PE) films—belong to a family of polymers known as polyolefins. A key chemical characteristic of these materials is that very few solvents can dissolve them. While this chemical resistance makes them incredibly effective at protecting food and liquids, it is the exact same trait that prevents their efficient recycling.
Researchers from the Department of Chemical and Biological Engineering at the University at Buffalo (UB)—led by Professor Paschalis Alexandridis, with contributions from Professors Marina Tsianou and Luis Velarde, and PhD student Ali Ghasemi—have now introduced experimental and modeling frameworks that could solve this global challenge on an industrial scale.
Decrystallization: The Key to Dissolving Polypropylene
The research team’s work represents a significant scientific milestone. Despite polypropylene being one of the most widely manufactured and used polymers globally, only four comprehensive scientific papers regarding PP dissolution have been published since the 1970s.
In their study published in the journal Polymers, titled “Polypropylene Dissolution Kinetics: Effects of Solvent, Temperature, and Particle Size”, the researchers combined computational modeling with physical experiments to understand the dissolution process at a microscopic level. During laboratory tests, they examined PP pellets—tiny polymer spheres also known as “nurdles”—in various solvents and at different temperatures.
One of the most critical technological findings of the research was that before the plastic pellets can fully dissolve in the solvent, they must first completely “decrystallize.” Understanding the exact mechanics of this microscopic phase is essential for optimizing future industrial processing.
Real-Time Spectroscopy in Polyethylene (PE) Analysis
In a separate study focusing on PE plastics (“Real-Time Quantification of Polyethylene Crystallinity via In Situ Mid- and Near-Infrared Correlation Spectroscopy: Melting and Dissolution”), the experts compared the behavior of polyethylene during its melting and dissolution phases.
To conduct these measurements, the team developed a specialized, temperature-controlled liquid flow-cell experimental apparatus. By utilizing mid- and near-infrared spectroscopy, they were able to track chemical reactions in real time. The extracted data allowed researchers to observe, down to the second, exactly when the decrystallization of PE occurred and when the long polymer chains physically began to separate (polymer chain disentanglement).
Why is this Process Superior to Pyrolysis?
Innovative solvent purification is a form of chemical recycling that industry experts believe could perfectly complement mechanical recycling, which currently struggles with flexible films. The researchers emphasize that the solvent-based process offers a much more favorable and greener alternative to the increasingly popular method of pyrolysis.
While pyrolysis relies on intense heat to induce the thermal breakdown of plastic chains into simpler oils and gases, solvent purification successfully preserves the complex polymer structure itself. This gentler chemical approach allows for the direct recovery and industrial reuse of high-quality materials, preventing the permanent destruction of valuable polymer chains.
A Second Chance for Millions of Tons of Plastic
The ultimate goal of this research is the development of a clean, industrially scalable, and sustainable recycling model. Regarding the scientific publications, Professor Paschalis Alexandridis emphasized:
“Solvent-based recycling of polyolefins offers a tremendous opportunity for plastic waste management and the recovery of useful materials. Our study facilitates the design and optimization of an energy-efficient and environmentally friendly, large-scale dissolution-precipitation recycling process for plastics that are currently landfilled or incinerated after use.”
With industrial fine-tuning, this technology could soon return millions of tons of plastic packaging—currently deemed unprocessable—back into the circular global economy.
Official Sources and References:
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University at Buffalo Official Research Release: Dissolution creates new path to recycling flexible plastics
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Phys.org News Portal (March 5, 2026): Researchers advance solvent-based recycling for flexible plastics
