Researchers at Washington State University have developed an environmentally friendly method to extract lignin from pine, allowing it to replace 20% of the fossil fuel-based chemicals in polyurethane foams. These foams are widely used in everyday products such as kitchen sponges, foam cushions, coatings, adhesives, packaging, and insulation. The global polyurethane market exceeded $75 billion in 2022, highlighting the significance of this breakthrough in creating more sustainable alternatives to petroleum-based plastics.
Lignin, the second most abundant renewable carbon source on Earth, makes up about 30% of nonfossil fuel carbon. However, it has traditionally been challenging to extract and is often contaminated or degraded during processes like papermaking and biorefining, limiting its value. As a result, most lignin is either burned for energy or used in low-value applications such as cement additives or animal feed binders. The researchers addressed this issue by using a mild, eco-friendly solvent to extract high-quality lignin from pine. This resulted in a structurally homogeneous material with excellent thermal stability, making it suitable for high-value applications.
When incorporated into polyurethane foam, the lignin-based formulation demonstrated mechanical properties comparable to conventional petroleum-based foams. This suggests that bio-based polyurethane foams could serve as viable, sustainable alternatives without sacrificing performance.
The development of lignin-based polyurethane foams has attracted interest from industrial partners, who recognize its potential for commercialization. Moving forward, the research team plans to collaborate with these partners to optimize and scale up production. The project received funding from the National Science Foundation’s Industry-University Cooperative Research Center for Bioplastics and Biocomposites (CB2), the USDA National Institute of Food and Agriculture, and WSU’s Office of Commercialization.