New, plant-inspired natural coatings can beat forever chemicals

Researchers at Washington University in St. Louis have developed a PFAS alternative that serves as an effective water-proof coating, without the toxic downstream effects on human health and the environment

Leah Shaffer 11.02.2026

Inside a plant’s vasculature, like this cross section of a linden tree branch, resides a water transport molecule that has inspired WashU chemical engineers to develop a PFAS alternative that uses plant waste and fatty acids to produce water-proof coatings. The research is a big step toward the eventual goal of replacing forever chemicals with nontoxic alternatives. (Photo: Shutterstock)

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Polyfluoroalkyl substances (PFAS) are known as “forever chemicals” because of the impact they make on the environment and human bodies. Much of modern manufacturing relies on these substances for safe packaging, medical devices, fire protection and for water-proof coatings. Despite the billions of dollars in economic burden its use places on human health and the environment, the PFAS itself is relatively affordable and abundant for manufacturing needs. So chemical engineers in the McKelvey School of Engineering at Washington University in St. Louis turned to a different material that is also affordable and abundant — lignin, or plant waste material. New research published in Matter outlines the chemical processes they used to turn lignin and fatty acids into a viable PFAS replacement called SLIP, or superhydrophobic lignin-integrated particles.

“We actually use this waste material to turn it into a valuable product,” said Joshua Yuan, Lucy & Stanley Lopata Professor and chair of the Department of Energy, Environmental & Chemical engineering at McKelvey School of Engineering. Yuan, who serves as director of the Carbon Utilization Redesign for Biomanufacturing (CURB) Center, has long taken inspiration from the natural world to find solutions to replacing petrochemical-based materials.

In SLIP, they found a viable water-proof coating to replace PFAS, without the toxic side effects. “It’s not going to stay in the environment forever and it can be degraded,” added Yuan.

To make SLIP, Yuan and his team including first authors Puneet Dhatt and Weiwei Li took inspiration from plant vascular tissue, called the xylem. Within the xylem is a waterproof molecule called suberin used to transport water throughout the plant. The team incorporated suberin’s structure into lignin particles by linking lignin to fatty acids, and further added a polylactic acid (PLA) binder. The resulting material demonstrated a highly superhydrophobic performance and included features of mechanical robustness and ultraviolet (UV) stability.

That’s not everything PFAS does, but it’s a substantial start, the researchers said, especially considering the sheer number of waterproof coatings used in modern manufacturing.

Tests show water literally bouncing off the new SLIP material. “The water will just run off,” Dhatt said, adding that the material was tested with wood-degrading fungus that showed the coating can break down into harmless organic matter within the expected time.

Lignin and fatty acid “evolved to degrade in the environment for a long time,” Dhatt noted, stating that the replacement material can help avoid the great cost to society of relying on forever chemicals.

The team collaborated with researchers at Texas A&M to estimate the cost savings of replacing PFAS. Looking at all the world impacts to human health and environmental degradation from forever chemicals, the Texas researchers estimated total avoided societal damage in replacing forever chemicals used in water proofing with SLIP could be up to $1.1 billion annually.

For now, they will continue to add attributes to this new coating. SLIP could be used in packaging and for construction material coatings, but the next step will be to make it oil and fireproof to vastly expand its applications. The team is also working on scaling up the process and integrating with biorefinery and paper and pulping industries.

“This study represents the perfect example, where we learn from the nature and design a sustainable material critical to our society, with a life cycle similar to nature polymers, where everything can degrade without causing harms,” Yuan said.

Dhatt PS, Li W, Chen Y, Meng X, Liu M, Fei C, Ragauskas A, Dai SY, Yuan JS. Bioinspired and biodegradable fluorine-free superhydrophobic coatings. Matter, 2026, 103068.

https://doi.org/10.1016/j.matt.2026.103068

Funding support provided through NSF CURB Engineering Research Center (NSF EEC 2330245); and DOE EERE BETO grants to J.S.Y. and S.Y.D.: DE-EE-0008250, DE-EE-0007104, and DE-EE-0009756. Yuan is a fellow of American Association for the Advancement of Science and Royal Society of Chemistry.

The McKelvey School of Engineering at Washington University in St. Louis promotes independent inquiry and education with an emphasis on scientific excellence, innovation and collaboration without boundaries. McKelvey Engineering has top-ranked research and graduate programs across departments, particularly in biomedical engineering, environmental engineering and computing, and has one of the most selective undergraduate programs in the country. With 170 full-time faculty, 1,492 undergraduate students, 1,284 graduate students and 22,000 living alumni, we are working to solve some of society’s greatest challenges; to prepare students to become leaders and innovate throughout their careers; and to be a catalyst of economic development for the St. Louis region and beyond.