Environment-friendly polyurethane foams are typically used in products such as kitchen sponges, foam cushions, and insulation.
A Greener Approach to Polyurethane Foam Production
The team used a “greener” form of lignin as a substitute for 20% of the fossil fuel-based chemicals in the foam.
The new foam was as strong and flexible as typical polyurethane foam.
“It’s quite novel in terms of the material we generate and the process we have,” said Xiao Zhang, corresponding author on the paper and professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering. “Our extracted lignin offers a new class of renewable building blocks for the development of bio-based value-added products.”
Challenges in Extracting Lignin for Sustainability
Lignin is a renewable carbon source but is difficult to extract from plants. It is usually separated during papermaking processes, but they can get contaminated.
The researchers therefore had to find a way to separate the lignin in the most efficient way.
Maritime Technology and Eco-Friendly Material Processing
The researchers used a mild, environmentally friendly solvent to separate a high-quality lignin from pine. Their formulation was homogeneous with good thermal stability – similar to native lignin.
When they tested their formulation, their product was stable and performed as well mechanically as the conventional foams.
“Our extracted lignin offers a new class of renewable building blocks for the development of bio-based value-added products,” said Zhang.
A Step Towards Sustainable Alternatives
“It’s basically a no-win situation if you’re using petroleum-based plastics,” he said. “The ultimate solution is to replace them with naturally derived materials.”
The environment-friendly polyurethane foams development may be able to tackle the growing waste problem associated with petroleum-based plastic materials – which take centuries to break down.
