Foam Insulation Made From Cellulose Nanocrystals Works Better Than XPS

©. Washington State University

If this gets into mass production we may be able to go plastic foam free.

UPDATE: In the press release, the material is compared to Styrofoam, which is a trademark owned by Dow Chemical for the blue XPS or extruded polystyrene foam. However, readers point out that the term is also used generically for the white expanded polystyrene used in coffee cups. I have written to the researchers involved for clarification.

We often complain about plastic foam insulation, noting that it is made with fossil fuels and greenhouse gases, is full of flame retardants, and puts out toxic fumes when it burns. But now researchers at Washington State University have developed a cellulose-based foam that actually is a better insulator than extruded polystyrene foam (XPS, commonly known as styrofoam).

According to the Washington State University press release,

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.

Cellulose nanocrystals have been around for a while, and are being used in making paper, paints and coatings. FPInnovations has been doing research on them and calls them "abundant, renewable, recyclable and not damaging to the environment."

The abstract published in Carbohydrate Polymers gives more technical detail on this new foam, and claims that the nanocrystalline cellulose (NCC) insulation has a thermal conductivity of 0.027 W/mK which is really low; polyurethane foams range from .022 to .028. Wood fibre insulation is up at .040 w/mK.

Researcher Amir Ameli says:

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.

The researchers are now "developing formulations for stronger and more durable materials for practical applications." Let's hope they can bring this to market soon; XPS foam insulations like Styrofoam have huge upfront carbon emissions, often more than they ever save. This could be big.