Diaper Dissection

Concept: Absorbency 
A material is absorbent if it is able to take in and hold liquid. If a substance is capable of absorbing fluid, it is considered absorbent.

Read Aloud: Plastics and Polymers Science Fair Projects by Madeline P. Goodstein

Ingredients:

      ·         Disposable Diapers (Different Brands)
      ·         Water
      ·         Pie Pans

 Demonstration:

      ·         Place a clean disposable diaper in an aluminum pie pan.

      ·         Pour ¼ cup water into the center of the diaper. Gently tip the diaper back and forth after adding the water.

      ·         Repeat until the diaper becomes saturated and starts to leak.

      ·         Record the amount of water the diaper was able to hold.

Experiment:

·         What brand of diapers absorbed the most liquid?

·         What brand of diapers absorbed the least liquid?

Observations:
Disposable diapers are made up of layers of superabsorbent polymers called sodium polyacrylate crystals. Superabsorbent polymers have the capacity to absorb massive quantities of water. They soak up water using the process of osmosis. When water comes in contact with the polymer, it moves from outside the polymer to the inside, which causes it to swell. The polymer chains have an elastic quality, but they can stretch only so far and hold just so much water. Sodium polyacrylate crystals can absorb up to 300 times their own weight in tap water.