Materials and Equipment
The materials listed below are for doing the experimental procedure exactly as written. However, you can make changes to the experimental procedure in order to use a different size measuring cup and/or a stovetop rather than a microwave. * Mugs or other heat-resistant cups (4); they should all be identical so as not to introduce another variable (See Variables in Your Science Fair Project), and large enough to hold more than 8 oz. of liquid * Masking tape * Pen or permanent marker * Teaspoon measuring spoon * White vinegar (at least 8 oz.) * Milk (at least 12 cups); nonfat, 1%, 2%, and whole milk will all work * Microwavable liquid measuring cup; should be large enough to hold 4 cups of milk like this one from Amazon.com * Microwave * Cooking or candy thermometer, such as this one from Amazon.com * Spoons (4) * Cotton cloth (12 squares, each 6 x 6 inches); cutting up old T-shirts works just fine * Rubber bands (4) * Clear plastic or glass drinking cups (4), each large enough to hold 8 oz. of liquid * Kitchen scale, should be accurate to 1 gram, such as this one from Amazon.com * Wax paper (in 12 identical pieces); each piece should be smaller than the weighing surface of the kitchen scale * Paper towels * Lab notebook * Optional (for fun): molds, cookie cutters, food coloring, paint, glitter, permanent markers
Experimental Procedure
Making Casein Plastic
This experiment uses hot liquids, so an adult 's help will be needed throughout. 1. Using the masking tape and pen, label the four mugs: 1, 2, 4, and 8. 2. Use the measuring spoon to add 1 teaspoon (tsp.) of white vinegar to the mug labeled "1," 2 tsp, to the mug labeled "2," 4 tsp. to the mug labeled "4," and 8 tsp. to the mug labeled "8." 3. Heat 4 cups of milk (1 quart) in a large measuring cup in the microwave. a. The exact amount of time needed will depend on your
Bibliography: These resources have more information about, and photos of, casein plastic: * Morgan, J. (2001, June 11). Welcome to the Caseino. Retrieved July 30, 2012, from http://www.caseino.internet-today.co.uk/ * Plastics Historical Society. (2011). Casein. Retrieved July 30, 2012, from http://www.plastiquarian.com/index.php?id=60