Milking it: Many products bought today are made from or contain plastic. How is it made, and what applications does it have?

Many of the products we buy today are made from, or contain, plastic. Imagine how headphones or computers might look without plastics.

This activity will allow your club to explore how to make plastics, and experiment with different ideas for applications. This session needs two club slots which are a week or more apart. Following the extras will create a longer project.

Plastic is traditionally made from crude oil, which is a non-renewable fossil fuel. Oil is also a ready made fuel which is cheap to convert into energy, but when burnt gives off atmospheric pollutants, including greenhouse gases, and we only have a limited supply.

Although we are increasing how much plastic we recycle, we need to look for alternative raw materials for making new plastics so that we do not waste the oil we have left, and to reduce the amount of greenhouse gases we release into the atmosphere.

The activity

What you need

  • Pint of whole milk
  • 20ml white vinegar
  • Water
  • Protective gloves
  • Muslin (or a cotton tea towel)
  • These figures can be scaled down so more groups can do the experiment using a ratio of 150ml of milk to 5ml of vinegar
  • This process can be done on a hob with a saucepan, spoon and sieve, or in the lab using a Bunsen burner (plus tripod, gauze and heatproof maat), beaker, stirring rod and sieve. You can use filter paper but this is very slow. Try coffee filters or tea strainers.

What to do 

Students will make a small amount of plastic. They need to think about what they are going to use it for, by designing a basic idea for a plastic, engineered product that has a short lifespan. For example, your group could design a seasonal decoration.

Engineering is ...

... thinking about how to manufacture and use plastics and plastic products. This is a good example of engineering being useful for our lives.

Materials and polymer engineers develop new products and improve upon existing ones. Have a look at related university courses at Entry requirements include A-Levels, Advanced Diplomas and Scottish Advanced Highers.

Related fields: Chemical engineering

Process Technology Apprenticeships ( provide training for a range of skilled occupations in the chemical, pharmaceutical, petro-chemical (oil) manufacturing and refining industries. These industries produce many of life’s necessities. The chemicals and pharmaceuticals industry makes products like pharmaceuticals, soaps and toiletries, while the petroleum refining industry is responsible for turning crude oil into fuels and lubricants.

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