[ad_1]
This Friday, July 9, we’ll explore the chemistry of milk plastic (or casein plastic) in our new video series for kids: Summer School with Live Science.
In this week’s episode, Live Science producer Diana Whitcroft will demonstrate how to make biodegradable plastic, called casein plastic, with milk and vinegar. She will be making jewelry in this tutorial, but families are welcome to do whatever they want, be it ornaments, keepsakes, decorations … anything!
Every Friday at 3 p.m. EDT (12 p.m. PDT), Diana will host Summer School With Live Science, which you can find live on Facebook, YouTube and Twitter pages. Each week the series will explore a different area of STEM (science, technology, engineering and math) through simple hands-on experiences that you and your child can do at home.
Disclaimer: It is strongly advised that all scientific experiments, recipes and methods be attempted only under adult supervision. Adults are required to handle or assist with all potentially hazardous utensils and ingredients. Always wash your hands thoroughly after trying an experiment. Avoid touching your face and eyes when performing experiments and, if possible, wear goggles or safety glasses. Do not ingest any of the ingredients during or after performing this experiment.
Plastic milk: Materials
Age range: 4-10 years old
- 1 cup whole milk
- 4 tbsp. White vinegar
- Small saucepan
- 1 large cup
- 3-4 paper towels
- Food coloring, beads, glitter (optional)
- Cookie Cutter (optional)
First step: choose your design
In Diana’s tutorial, she will show you how to make a casein ring. But you and your children are encouraged to make any decorative items you desire, such as ornaments or keepsakes. Feel free to double the recipe and make bigger items. Embellish with beads or sequins too!
Step two: make casein plastic
Heat the milk in a small saucepan. Do not bring to a boil. While waiting for your milk to heat up, add the vinegar to your mug. If you double the recipe, consider switching from a mug to a mixing bowl. Once the milk has barely started to boil, remove it from the heat and add it to your cup of vinegar. Right away you will notice curdling, but allow your mug to cool for 3-5 minutes before handling it.
Third step: mold your object
With a spoon, do your best to separate the milk solids from the liquid and transfer them to a paper towel. Knead about a minute before adding your color and decorations. Continue kneading, gently pressing what is now dough against your paper towel to release as much liquid as possible. When your dough is dry enough, it should look like a plasticine-like consistency. Shape it however you want.
Document this experience and send us images on social media or at [email protected]. We would love to see your results so we can feature them in our photo gallery!
What is so important about casein plastic?
Milk contains the molecules of a protein called casein. When milk is warmed up and added with acid (vinegar in this case), the casein molecules unfold and reorganize into a chain of monomers called a polymer. If the process of making cheese comes to your mind when you try this experiment, you would be on to something because the processes are very similar! In fact, the word casein means “cheese” in Latin, and the wet substance you’ll use to mold your jewelry looks a bit like cottage cheese. This polymer will harden within 24 hours; and while not as durable as most industrial plastics, casein is biodegradable and quite versatile.
Casein plastic was first introduced in the early 1900s and is still used today to make such items as buttons, buckles, jewelry, fountain pens, beauty accessories and more. again. To further strengthen the structural integrity of this plastic, many manufacturers have added the step of soaking it in formalin, which is a 5% solution of formaldehyde in water. Casein plastic was used to make jewelry for Queen Mary I of England, who ruled England from AD 1553 to AD 1558.
Originally posted on Live Science.
[ad_2]
Source link