Engineering Minute

Engineering Minute – Environmentally-Friendly Styrofoam Alternative

Engineers at Washington State University have developed a plant-based, environmentally-friendly material that offers an alternative to Styrofoam. The material is made of cellulose nanocrystals and works better at insulating than Styrofoam. The nanocrystals are produced using a simple manufacturing process using water as a solvent instead of harsh chemicals. The team's work was recently published in the journal Carbohydrate Polymers. 

 

An environmentally-friendly, plant-based material that for the first time works better than Styrofoam for insulation.
An environmentally-friendly, plant-based material that for the first time works better than Styrofoam for insulation. Credit: Washington State University

“We have used an easy method to make high-performance, composite foams based on nanocrystalline cellulose with an excellent combination of thermal insulation capability and mechanical properties,” says study lead Amir Ameli, assistant professor in the school of Mechanical and Materials Engineering at Washington State University. “Our results demonstrate the potential of renewable materials, such as nanocellulose, for high‑performance thermal insulation materials that can contribute to energy savings, less usage of petroleum-based materials, and reduction of adverse environmental impacts.”

 

From the Washington State University article: "Researchers have been working to develop an environmentally friendly replacement for polystyrene foam, or Styrofoam. The popular material, made from petroleum, is used in everything from coffee cups to materials for building and construction, transportation, and packaging industries. But, it is made from toxic ingredients, depends on petroleum, doesn’t degrade naturally, and creates pollution when it burns.

While other researchers have created other cellulose-based foams, the plant-based versions haven’t performed as well as Styrofoam. They are not as strong, don’t insulate as well, and degraded at higher temperatures and in humidity. To make cellulose nanocrystals, researchers use acid hydrolysis, in which acid is used to cleave chemical bonds.

In their work, the WSU team created a material that is made of about 75 percent cellulose nanocrystals from wood pulp. They added polyvinyl alcohol, another polymer that bonds with the nanocellulose crystals and makes the resultant foams more elastic. The material that they created contains a uniform cellular structure that means it is a good insulator. For the first time, the researchers report, the plant-based material surpassed the insulation capabilities of Styrofoam. It is also very lightweight and can support up to 200 times its weight without changing shape.  It degrades well, and burning it doesn’t produce polluting ash."

 

Read more about the environmentally-friendly alternative to Styrofoam at Washington State University