A new study published in ACS Sustainable Chemistry & Engineering concludes that foams made from cellulose diacetate (CDA) using Eastman's compostable Aventa materials break down quickly in the ocean. The study reveals that these biodegradable CDA-based foams are commercially useful and will not contribute to ocean plastic pollution.
Scientists from Woods Hole Oceanographic Institution (WHOI), a top ocean research organisation in the USA, led the study. The research showed that CDA foams made with Aventa lose up to 70% of their weight after being in seawater for 36 weeks. In comparison, foams made from polystyrene, often used in food packaging, did not break down at all. CDA foams break down much faster than other materials tested in similar conditions, doing so at a rate more than four times faster than paper and up to 1,000 times faster than plastics such as solid polypropylene, polystyrene, and polylactic acid.
"Foaming biodegradable bioplastics like Aventa offer a promising strategy to reduce the environmental impact of frequently mismanaged consumer plastics, particularly in food packaging applications," said Collin Ward, associate scientist at WHOI and lead researcher for the study. "These materials not only degrade rapidly in the ocean but also support circularity and material efficiency."
The study noted that replacing polystyrene with CDA-based foams for food packaging could save over $1 billion by reducing pollution costs, but emphasised the need to understand the overall environmental impact in order to prevent replacing one problem with another. Aventa is a cellulosic material derived from sustainable wood pulp, ensuring a renewable and sustainable beginning of life, and its compostability translates into a sustainable end of life. Outside the EU, it is currently being used as a compostable solution for single-use applications such as disposable straws and cutlery.
"Traditional plastic foams face challenges in end-of-life management, often unintentionally ending up as plastic pollution in the environment," said Jeff Carbeck, vice president of Eastman corporate innovation and care solutions technology. "Eastman Aventa materials offer a sustainable alternative, and this research shows that CDA-based foams will not contribute to persistent marine plastic pollution."
For more information, read the full article in the October 2024 issue of ACS Sustainable Chemistry & Engineering.