From left, Associate Professor Hoyong Chung and postdoctoral researcher Arijit Ghorai display the two phases of their degradable polymer at the Dittmer Chemistry Lab at Florida State University. Credit: Scott Holstein/FAMU-FSU College of Engineering
Researchers from the FAMU-FSU College of Engineering have developed a novel alternative to traditional plastics that fully degrades at the end of its life. Additionally, the plastic does not break down into microplastics or other toxic substances and can be recycled without losing its original properties.
Published in Advanced Functional Materials, the plastics are made of carbon dioxide and lignin, a low-cost byproduct of biofuel and paper production.
“Our study takes the harmful greenhouse gas CO2 and makes it into a useful raw material to produce degradable polymers or plastics,” said Hoyong Chung, associate professor in chemical and biomedical engineering. “We are not only reducing CO2 emissions, but we are producing a sustainable polymer product using the CO2.”
The study is the first to directly synthesize a cyclic carbon monomer made of CO2 and lignin. By linking many of these monomers together, scientists can produce synthetic polymers that can be designed to achieve countless applications. Synthesis of the material also occurs at lower temperatures and pressures than traditional petroleum-based plastics.
The key to the material's recyclability is depolymerization which can convert the polymers to pure monomers. These monomers can then be recycled indefinitely and can be used to produce a polymer with the same characteristics and quality as the original.
“We can readily degrade the polymer via depolymerization, and the degraded product can synthesize the same polymer again,” said Chung. “This is more cost effective and keeps it from losing original properties of polymers over multiple recycling. This is considered a breakthrough in material science, as it enables the realization of a true circular economy.”
The material developed by the team could have countless applications including manufacturing low-cost short lifespan plastic products for use in numerous industries. The team also anticipates the plastic to be useful for biomedical applications and energy storage with additional optimization and development of the material.