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Diaper Science: How Hydrogels Absorb Water

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Areas of Science
Time Required
Short (2-5 days)
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Many disposable diapers contain a polymer, called sodium acrylate, which is useful for absorbing water. Do background research to learn about sodium acrylate, and how it reacts with water. Make sure that you understand the terms hydrophilic, polarity, hydrogel and hydrogen bonding. Cut out the middle, padded section of a disposable diaper. Cut this into equally-sized square pieces, approximately 10-12 cm on a side. Remove some of the stuffing material so that you can staple the open ends closed. Measure water into a quart jar to fill it half-way. Immerse a diaper pad square in the jar and leave it for at least twenty minutes. Take out the diaper pad square, and allow any dripping water to go back into the jar. Measure how much water is left in the jar, and subtract from the original amount to see how much water the diaper pad square absorbed. Here are some questions you can think about answering with this project.


Goodstein, M., 2004. Plastics and Polymers Science Fair Projects: Using Hair Gel, Soda Bottles, and Slimy Stuff. Berkeley Heights, NJ: Enslow Publishers.
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General citation information is provided here. Be sure to check the formatting, including capitalization, for the method you are using and update your citation, as needed.

MLA Style

Science Buddies Staff. "Diaper Science: How Hydrogels Absorb Water." Science Buddies, 25 May 2023, https://www.sciencebuddies.org/science-fair-projects/project-ideas/Chem_p035/chemistry/polymer-absorbance-diapers. Accessed 7 June 2023.

APA Style

Science Buddies Staff. (2023, May 25). Diaper Science: How Hydrogels Absorb Water. Retrieved from https://www.sciencebuddies.org/science-fair-projects/project-ideas/Chem_p035/chemistry/polymer-absorbance-diapers

Last edit date: 2023-05-25
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