An environmentally friendly foam was developed that can be used as an alternative to polystyrene foam, or Styrofoam™. The foam is made mostly from nanocrystals of cellulose, the most abundant plant material on Earth. The researchers also developed an environmentally friendly and simple manufacturing process to make the foam using water as a solvent instead of other harmful solvents.
Made from petroleum, Styrofoam 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, does not 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.
The new material 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 contains a uniform cellular structure that means it is a good insulator and is very lightweight and able to support up to 200 times its weight without changing shape. It degrades well and burning it doesn't produce polluting ash.