Gelatin Bioplastics 

Bioplastics

Bioplastics are plastic materials produced from renewable biomass sources, rather than fossil fuels. In this workshop you will learn a hands-on technique to teach your students about a bioplastic alternative that is environmentally safer for our planet. We will discuss Gelatin Bioplastic; the science behind it and how you can incorporate it into your science curriculum!

The Science Behind Gelatin Bioplastics:

Bioplastics are biodegradable materials that come from renewable sources and can be used to reduce the problem of plastic waste that is suffocating the planet and contaminating the environment. Plastic is the third most commonly used petroleum derivative in the world; each year 200 million tons of plastic are consumed on the planet. It comes from a non-renewable source (petroleum), it is contaminating and non-biodegradable (it can take more than 1000 years to decompose).

Why is gelatin a good source for bioplastics? Gelatin is created by breaking down collagen which is found in all animals where its function is to bind cells together. Collagen is a very long chain of amino acids, the building blocks of proteins, that bonds to itself in a triple helix pattern.

Gelatin is long chains of hundreds of amino acids. At room temperature it is solid, but when you heat it up the bonds between the chains loosen, allowing them to slide and stretch apart. Gelatin also has a strong affinity for water. Hydrogen atoms that are attached to the side of the chains can bond with water molecules. When you heat up and mix gelatin and water you are weakening the chains, then during the cooling process those hydrogen atoms form connections with the water molecules. 

In gelatin bioplastics a lot of gelatin is added to a fairly small amount of water. All those water molecules bond with the hydrogen molecules, then the amino acid chain also starts to bond with itself, trapping those water molecules within its complex 3D structure. If you use more water, the result would be a gummy candy consistency or even a jello consistency. But in this experiment all the water molecules are used up, so once it finishes curing you end up with a very hard plastic.