Making casein plastic

Lesson: Science

Our science topic this term is materials. Here we are using milk and vinegar to make a type of plastic called casein plastic. Milk contains molecules of protein called casein. When milk is heated and combined with an acid, such as vinegar, the casein molecules reorganised into long chains. Each casein molecule is called a monomer and the chain of casein molecules is called a polymer. All plastics are made polymers.