On June 17, 2026, researchers at the University of Minnesota Twin Cities developed a new strategy to help compostable plastics degrade faster under everyday composting conditions, thereby reducing the need for specialized industrial facilities.
The paper was published in *ACS Central Science*, a peer-reviewed journal dedicated to publishing the most compelling, high-impact discoveries in the physical and life sciences where chemistry plays a central role.
Polylactic acid (PLA) is a renewable and degradable plastic commonly found in everyday items such as compostable food packaging, cups, and cutlery. Although these items are labeled as "compostable," access to suitable industrial composting facilities is scarce.
"The degradability of these plastics is largely limited to industrial composting conditions," said Marc Hillmyer, a McKnight Presidential Chair Professor in the Department of Chemistry and co-corresponding author of the paper. "Unfortunately, only about 18% of the U.S. population has access to industrial composting facilities. Consequently, many PLA products end up in landfills after disposal."
Researchers discovered that adding trace amounts of 2-sulfobenzoic acid cyclic anhydride (SAn) significantly accelerates the hydrolytic degradation of PLA. When exposed to moisture and composting temperatures over time, SAn generates acidic compounds that help break the plastic's molecular bonds from within. Essentially, the additive acts as a "masked acid," remaining dormant during normal use but activating under the combined influence of moisture, temperature, and time during the composting process.
Because the process requires only 0.01% of the additive, the plastic retains its strength and durability during everyday use. Furthermore, the additive enables PLA to decompose under milder, lower-temperature conditions than those required by industrial composting facilities. "While bio-renewable and biodegradable plastics represent a major step forward, they lose their environmental value if they simply end up in landfills," said Christopher Ellison, a professor in the Department of Chemical Engineering and Materials Science and a co-senior author of the paper. "By introducing this new type of additive, we can enable households to use packaging that is more sustainable and suitable for home composting."
Next, the researchers plan to apply this method to a wider range of commercial plastics. They are also conducting rigorous ecotoxicity tests to ensure that plastics containing the additive can reintegrate into the soil safely, without harming the environment or local ecosystems.
