A new discovery offers a promising way to break down stubborn plastics like Plexiglass into their original building blocks, potentially revolutionizing recycling.
Unlike conventional methods that degrade plastic quality through mechanical reprocessing, this chemical approach allows full recovery of monomers, making high-quality reuse possible.
Breaking Down Plastics into Monomers
Scientists have developed a new method to break down plastics like Plexiglass into their original building blocks, known as monomers, making them easier to reuse. This breakthrough could help reduce plastic waste, which continues to be a growing environmental problem.
Traditional plastic recycling typically involves shredding, cleaning, and remelting the material. However, this process degrades the plastic’s quality over time. In contrast, breaking plastics down into monomers allows for a more thorough purification, enabling them to be reformed into high-quality materials without loss of performance.
Plastic Waste Facts (Yearly Estimates)
- Global Plastic Waste: Over 400 million metric tons of plastic waste are generated annually.
- Recycled Plastic: Only about 9% of plastic waste is successfully recycled.
- Landfills & Incineration: Around 19% is incinerated, while nearly 50% ends up in landfills.
- Ocean Pollution: An estimated 11 million metric tons of plastic enter the ocean each year.
How Light and Solvents Enable Plastic Breakdown
In their research, Hyun Suk Wang and colleagues discovered that exposing Plexiglass and similar plastics to violet light in a dichlorobenzene solvent can efficiently break them down into their original monomers. The reaction appears to be driven by chlorine radicals released from the solvent, which help initiate the breakdown process.
The researchers highlight that this method can be performed on a larger scale and allows for precise control over the breakdown process. They suggest it could become a widely applicable and efficient approach to plastic recycling.
Reference: “Visible light–triggered depolymerization of commercial polymethacrylates” by Hyun Suk Wang, Mikhail Agrachev, Hongsik Kim, Nghia P. Truong, Tae-Lim Choi, Gunnar Jeschke and Athina Anastasaki, 20 February 2025, Science.
DOI: 10.1126/science.adr1637
