Scientists have made a major breakthrough in the field of bioplastics by creating a new form of cellulose diacetate (CDA) that decomposes 15 times faster than traditional forms. Tested in realistic ocean conditions, foamed CDA can be used to replace Styrofoam in food packaging, significantly reducing environmental plastic pollution.
Study on biodegradable plastic
For years, researchers at Wood Hole Oceanographic Institution (WHOI) have been studying which types of plastic have the shortest and longest lifespans in the ocean and which types of plastic products, such as straws and food packaging, contribute the most to the ocean. plastic pollution. With the development of more biodegradable materials such as cellulose diacetate (CDA), a plastic-like polymer derived from wood pulp, researchers are trying to replace traditional plastics without harming marine ecosystems.
Groundbreaking development in bioplastics
After years of testing, the new version of CDA turned out to be the fastest-degrading bioplastic material tested in seawater. It is also a promising alternative to other foams such as Styrofoam, which can persist in the environment for many years. In a new article published today (October 17) ACS Sustainable Chemistry and EngineeringWHOI scientists Brian James, Colleen Ward, Chris Reddy, Yanchen Sun and Kali Pate found that adding tiny pores, called foam, to the CDA material causes it to decompose. It is 15 times faster than solid CDA and even beats paper.
“What concerns me most about this study is its translational nature. This study is the culmination of years of research focused on understanding the fundamental controls on the biodegradation of CDA in the ocean,” said Ward, the study’s senior author. He and his WHOI team collaborated with scientists from Eastman, a bioplastics company; these scientists funded, contributed as co-authors, and provided materials for the research.
“We turned the basic knowledge into the design of a new material that not only meets consumer needs but also decomposes in the oceans faster than any other plastic material we know of, even faster than paper. “This is a huge success story in an industry that often focuses on the negative aspects of plastic pollution rather than trying to solve the problem,” Ward added.
Advances in materials science
The study involved monitoring both foamy CDA and solid CDA in a continuous-flow tank of seawater from Martha’s Vineyard Sound in a specially designed WHOI laboratory. Researchers also control temperature, light and other environmental variables to mimic the natural marine environment.
“Using tanks with a constant flow of seawater allows us to bring the dynamics of the microbially active ocean into the laboratory. The ocean is constantly changing, and it was important that we recreate this environment by adding microbes and nutrients, creating a much more ecologically realistic experiment,” explained lead author James. After 36 weeks, the team found that the CDA foams had lost 65-70% of their original mass.
In a previous study using dynamic seawater tanks, researchers tested straws made of standard plastic, paper, solid CDA, and foamed CDA and found that solid CDA and paper straws lost mass the fastest. The scientists then compared two straws made from CDA, one from solid CDA and the other from foamed CDA, and found that the degradation rate of the foam was 190% faster than its solid counterpart, resulting in a shorter estimated environmental lifespan than paper straws. . .
“As a materials scientist and engineer, it was exciting to show that foams can be material efficient, meaning they can achieve functionality and reduce costs and environmental impacts using the least amount of material possible,” James said. “They can also be one of the least sustainable types of materials when made from biodegradable plastic.”
Impact on industry and environment
Replacing single-use plastics such as Styrofoam and takeout containers, which are non-biodegradable and regularly end up in oceans, is one of the material’s most urgent applications, according to the study’s authors. Foamed CDA products are already on the market, with Eastman producing a compostable lightweight foam CDA tray designed to replace plastic trays used in industrial food packaging.
“Partnerships between industry and academia are critical to accelerating solutions to the most pressing global challenges, where academia can provide unique insights and industry partners can use that insight to develop solutions at scale,” said Jeff Carbeck, vice president of corporate innovation. . “This is how our collaboration with WHOI works; “They have greatly improved our understanding of how our commercial and development materials deteriorate.”
Karbek emphasized that this research shows the potential of CDA foam to solve problems related to single-use plastic packaging. “The properties of foam are ideal for many types of packaging and insulation, and this research shows that foams made from biodegradable materials will rapidly degrade in the marine environment if they accidentally get there. Using biodegradable materials in consumer products will help protect our environment, reduce plastic pollution and ensure sustainability for future generations.” “This is an important step towards encouraging
“One of the advantages of working with an industry partner is that we can ensure the scalability of the new technology. One of the criteria in developing the new material was that it had to be a turnkey alternative to Styrofoam, meaning that companies converting raw CDA into biodegradable foam do not need to invest in new equipment,” he said. Ward explained. “Encouraging new types of plastic that are not made from fossil fuels, can be composted, and do not persist in the environment due to pollution could be a win-win for consumers and the environment.”
Source: Port Altele
