Top 10 Eco-friendly Substitutes for Plastic


Milk Protein

Penn & Teller Tell A Lie: Clothes From Milk
Forget plastics made from milk. In this video, Penn and Teller meet a microbiologist turned fashion designer who's making milk into clothing.

All newborn mammals survive on it. Without it, there would be no ice cream. There's really no denying the value, or pleasure, of milk.

Now scientists say it could help to produce a biodegradable plastic for furniture cushions, insulation, packaging and other products. Yep, researchers are revitalizing the idea of converting casein, the principal protein found in milk, into a biodegradable material that matches the stiffness and compressibility of polystyrene.

Casein-based plastic has been around since the 1880s, when a French chemist treated casein with formaldehyde to produce a material that could substitute for ivory or tortoiseshell. But although it's ideal for jewelry that even Queen Mary admired, casein-based plastic is too brittle for much more than adornment.

Scientists have found a way make the protein less susceptible to cracking, thanks to a silicate clay called sodium montmorillonite. Freezing sodium montmorillonite into a spongelike material called an aerogel, they infused the porous network of clay with casein plastic. The result? A polystyrene-type material that, when put in a dump environment, begins to degrade completely [source: The Economist]. The modern milk-based plastic doesn't crack as easily, thanks to that silicate skeleton, and they even made the stuff less toxic by substituting glyceraldehyde for formaldehyde during the process.

The future of casein plastic isn't certain, but swapping it for petroleum-based polystyrene would certainly give us another reason to love milk.