A combination of milk protein and ordinary clay may represent a biodegradable alternative to the Styrofoam and plastics we dump in our landfills.
Scientists at Case Western Reserve Universityincluding researcher David Schiraldi have discovered a way to make a stronger, lighter, and far more biodegradable packaging option than those currently on the market.
Most plastic packing and filling products suffer from the same slippery problem: oil. Much of it is imported from other countries, but no matter its source, it ends up in the same place: a landfill. In many cases, plastics and Styrofoam either break down slowly or not at all, and in rare instances create toxic intermediary byproducts as they whither away.
Looking for a new option, the Case team turned to what appears at first to be an unlikely source: milk. In actuality, milk protein – of which 80% is a substance called casein – is already used in glue and coating materials. Unfortunately, the cow-derivative isn’t particularly strong, and a good hard rain or dip in water will degrade any product that is casein-based.
In order to improve casein’s utility, Schiraldi’s team mixed in ordinary clay and extra amounts of glyceraldehyde, the molecule responsible for ensuring that casein sticks together. The resulting substance was freeze-dried and had its water removed, placing it firmly into the category of spongy aerogels, often termed “liquid smoke” for their light and airy features.Aerogels: in all their light and floatly glory. The milk/clay hybrid was then cured in an oven and stress-tested, and guess what? It was easily determined to be strong enough to operate as a packing, stuffing and insulating material. And the best part? The stuff is biodegradable – with 30% of it breaking safely down and away in the first 30 days.
This isn’t in the product stage just yet, but we see a bright future for this new material – so long as the established packing industry doesn’t suddenly prove lactose intolerant.Source: EurekAlert