Tiny droplets use pressure to unlock new routes to degradable plastics

Tiny droplets use pressure to unlock new routes to degradable plastics Sadie Harley Scientific Editor Robert Egan Senior Editor Using a new technique, a research group led by Osaka Metropolitan University (OMU) has substantially increased the range of plastics that can be degraded naturally. The study is published in the journal Macromolecules. "Our findings greatly expand the range of materials available for the production of degradable plastics," associate professor Yukiya Kitayama of the Graduate School of Engineering said. To make plastics degradable, researchers typically look at their basic building blocks, known as monomers, and how chemical bonds bind them together. In the natural environment, many plastics don't fully degrade because of the bonds, causing them to break down into microplastics, which persist in the environment. Tiny droplets drive unusual reactions Instead of taking the typical molecular design approach to the problem, the research group looked to changing the physical environment of the chemical reactions using pressure, a seldom-used technique. To maximize pressure, they performed the reactions inside nanoscale droplets. This took advantage of a principle known as Laplace pressure, where the smaller a droplet is, the greater the pressure inside it is due to surface tension. The tiny droplets created such intense pressure that they promoted chemical reactions that would not usually occur. The researchers were able to unlock normally inaccessible parts of the monomer's ring structure and use them to create different bonding locations. The enhanced control over the process enabled the creation of plastics with more degradable properties. More materials, simpler manufacturing As a result, materials that were previously considered unsuitable for polymerization could be polymerized, increasing the range of plastics that could be created without the need for complex structural modifications. "Our method could be used to develop environmentally friendly plastics that can be reliably degraded after use and will help address the growing problem of plastic waste," Kitayama said. "Because the method does not require particularly complex or specialized processes, it can be readily implemented in industrial manufacturing," he continued. "The concept of using pressure as a tool to drive chemical reactions represents a new approach that could open new possibilities across a broad range of chemical processes." More information Kaito Fuji et al., Laplace Pressure-Enabled Radical Ring-Opening Polymerization of a Thionolactone, Macromolecules (2026). DOI: 10.1021/acs.macromol.6c01012 Provided by Osaka Metropolitan University