It’s time to get sustainable with five fun and fascinating fast facts about plastic, an interview with Dr Charlotte Beloe, a scientist who knows a lot about microplastics in the ocean, and a cornflour bioplastic activity for you to try yourself at home.

Presented by Jenny Lynch and Matilda Sercombe. Written and produced by Jenny Lynch. Music by Purple Planet Music. Sound effects by Pixabay.

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Episode content:

00:00 Introduction and fast facts

03:26 Recycling plastic

05:14 Interview with Dr Charlotte Beloe

10:29 Bioplastic activity

Bioplastic activity instructions

Ingredients: 1 tablespoon of cornflour, 4 tablespoons of water, 1 teaspoon of vinegar, ½ teaspoon of glycerine, and a few drops of food colouring.

Kitchen equipment: a small saucepan, stove or hotplate, metal spoon for stirring, and a baking tray on a heat-proof surface.

1. Add all of the ingredients to the small saucepan and stir with the metal spoon until everything is well mixed.

NOTE: An adult must assist with the next steps that involve heating the mixture on a stove or hotplate.

1. Stir the mixture over a medium heat and keep stirring with the metal spoon until the mixture starts to boil.
2. Reduce the heat and keep heating and stirring for 2 or 3 minutes.
3. Pour the hot mixture onto the baking tray and spread it out to make a thin sheet.
4. Leave the sheet of bioplastic film to cool and dry for 1-2 days. The finished bioplastic film should be see-through and flexible.

This recipe can also be used to make moulded bioplastic shapes by pouring the hot mixture into silicone moulds (e.g. silicone ice-cube trays). The bioplastic in this activity is ‘compostable’, which means it will break down in a compost heap or if it is buried in the ground.

Corn flour contains starch which is made up of ‘amylose’ and ‘amylopectin’ molecules which are both made up of glucose molecules. Heating corn flour with water causes some of the starch to form long chains. Vinegar affects the formation of the long chains. The glycerine acts as a ‘plasticiser’ which is a chemical that can change the softness and pliability of a plastic. Changing the amount of glycerine in the recipe will change the properties of the bioplastic film.