Milk and Clay Make for a Potential Styrofoam Alternative: Aeroclay

Ah, foamed polystyrene. Technically its called closed-cell extruded polystyrene, or Styrofoam.  The Dow Chemical trademarked product is generally used to describe polystyrene foam.  Sourced from fossil fuels, it takes a while to decompose, and many municipalities do not pick up the popular packaging material as part of their curbside recycling programs.  The best possible option for now is to reuse and reuse polystyrene as packing material—after all it will not go anywhere for a while.  Some Case Western University researchers, however, believe they have found a more natural alternative.

A student of David Schiraldi, a polymer scientist at the venerable Cleveland university, stumbled into the idea by accident.  The student freeze dried some clay and became intrigued by the physical change in the material.  Schiraldi’s research team began to mix the clay with various materials, and a young start up was born.The research team added a bovine milk protein, casein—you know, that milk-based powder that is added to many fake cheeses, which in turn renders them non-vegan (sorry if I ruined your love of that soy- or almond-based cheese, but read the labels!)  Well, upon adding that casein powder, Schiraldi’s crew noticed that the freeze-dried clay and milk byproduct created a light and puffy material very similar to polystyrene.

The process smacks of a mash-up of Julia Child and The Muppet Show’s Dr. Bunsen Honeydew.  Clay and water go into a mixer, followed by the casein powder.  Then a smidge of a glycerol-based material, which strengthens the solution’s bonds.  The concoction is poured into a mold, then frozen, and finally freeze dried.  The result is a 98% bio-based material that breaks down in about 45 days under industrial compost conditions.

The experimentation led to the founding of Aeroclay, an eco-polymer firm that strives to provide an alternative to that pesky polystyrene.  The company has a few issues:  they have got to ensure that the product does not smell like sour milk.  And of course, manufacturing has to scale and be cost-competitive.  Other companies, meanwhile, are exploring other forms of packaging materials, such as Steelcase and its mushroom-derived foam products.  Many wring their hands of the use of polystyrene, but not many alternatives exist for casing valuable products like computers.  On the other hand, some imaginative businesses are finding a way to recycle polystyrene and create jobs.  With a one-two punch of increased reuse and a more eco-friendly alternative, we will win in the long run either way.

Leon Kaye has written for Triple Pundit since 2010 . He is the founder and editor of Based in Fresno, California, he is a business writer and strategic communications specialist. His work is has also appeared on The Guardian's Sustainable Business site and on Inhabitat and Earth911. His focus is making the business case for sustainability and corporate social responsibility. Contact him at You can also reach out via Twitter (@LeonKaye) and Instagram (GreenGoPost).