Trace additive unlocks faster bioplastic biodegradation without losing transparency or strength

PLA plastic (left piece) usually takes months to break down in industrial composting facilities, but incorporating a sprinkling of an organic additive dramatically speeds the process for a modified PLA plastic (right piece) to less than three weeks. Credit: Jinsol Yook

Compostable plastics could be part of a solution to the world's plastic waste problem. But currently these materials need industrial composting facilities to break down. In a step toward making a home-compostable plastic, researchers reporting in ACS Central Science have augmented polylactide (PLA)—a widely used biobased and compostable polymer—with a small amount of an additive. Tests show it helps the material degrade substantially faster without sacrificing critical qualities like strength or transparency.

"PLA can be made to degrade much more effectively under practical composting conditions without compromising the properties that make it useful in everyday applications," says Marc Hillmyer, a corresponding author of the paper.

PLA is currently found in products such as food packaging, textiles and biomedical devices, and it accounts for roughly two-thirds of total bio-based and biodegradable plastics production worldwide. "Composting is considered one of the most effective end-of-life strategies for PLA products, especially food-contaminated single-use products, because it eliminates the need for additional sorting and washing processes," says Hillmyer. This process converts organic waste into environmentally innocuous products such as small organic acids.

However, PLA "is only industrially compostable in engineered environments where it degrades over a few months," he adds. The bioplastic usually needs high temperatures and humidity to break down over practical timescales.

A masked-acid workaround

Inspired by this limitation, Hillmyer, Christopher Ellison and colleagues wanted to develop a PLA-based material that breaks down faster and under a broader set of conditions. Instead of adding organic acids directly, which can weaken PLA during processing, the team blended PLA with small amounts of organic anhydrides. These compounds are "masked acids" because, once exposed to water, they activate and help catalyze the breakdown of the plastic's polymer chains.

The researchers created two plastic films containing different organic anhydrides: phthalic anhydride or 2-sulfobenzoic acid cyclic anhydride. They found that PLA blends modified with either substance maintained their mechanical properties, including strength and transparency, compared with pure PLA films.

Faster breakdown at lower heat

The 2-sulfobenzoic acid cyclic anhydride additive worked especially well, even at trace levels as low as 100 parts per million. Under industrial composting conditions at 58 degrees Celsius (136 degrees Fahrenheit), PLA containing 0.1% of this additive completely degraded within 21 days, surpassing unmodified PLA, which reached 83% biodegradation after 90 days. The researchers also had success improving the biodegradability of the modified PLA at around 45 degrees Celsius (113 degrees Fahrenheit), a temperature within the range of healthy home composts.

The authors say their approach could expand the practical use of PLA by helping it degrade not only in industrial composting facilities but also in home composting bins. However, more testing is still needed to understand how modified PLA materials behave in various settings and environments.

Publication details

Jinsol Yook et al, Dramatic Enhancement in Polylactide Hydrolysis and Biodegradability Utilizing Low Levels of Organic Anhydrides As Masked Acids, ACS Central Science (2026). DOI: 10.1021/acscentsci.6c00395

Who's behind this story?

Gaby Clark

MA in English, copy editor since 2021 with experience in higher education and health content. Dedicated to trustworthy science news.

Full profile →

Robert Egan

Bachelor's in mathematical biology, Master's in creative writing. Well-traveled with unique perspectives on science and language.

Full profile →

Citation :

Trace additive unlocks faster bioplastic biodegradation without losing transparency or strength (2026, June 18)

retrieved 18 June 2026

from https://phys.org/news/2026-06-additive-faster-bioplastic-biodegradation-transparency.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no

part may be reproduced without the written permission. The content is provided for information purposes only.