Published on 10/09/08

Diapers to dirt: Hydrogels focus of national youth science day

By Stephanie Schupska
University of Georgia

Thin strips of fabric floated through the air in Athens, Ga., on Oct. 8 as University of Georgia 4-H students ripped open disposable diapers to study their stuffing, joining students from across the nation to perform the first national science experiment for the 2008 National Youth Science Day.

Together, they turned diapers inside out to find hydrogels, the polymers that give diapers liquid-absorbing ability. A dot-sized hydrogel can hold up to 500 times its weight in water.

“We’re doing this experiment all over the nation. And if we can coordinate this, what other projects can be coordinated and replicated across the nation?” asked UGA sophomore and collegiate 4-H’er Laura Warren of Camilla, Ga.

The 4-H’ers collected the powdery gels and added water to see how much liquid a tablespoon of them could hold.

They then added dry hydrogels to soil, placing that mix and a control mix of plain soil in modified soda bottles. Then, they dumped dyed water into each sample. The liquid drained right through the control but stayed in the soil in the bottles containing the hydrogels.

Some students got messy, like senior Steven Dasher of Glennville. He now sees diapers in a new light.

“It was interesting to learn about the many different applications of such an everyday item,” he said.

Hydrogels are networks of polymer chains that do not dissolve in water. They can contain over 99 percent water and occur both naturally or can be manmade. Besides stuffing them in diapers, scientists are also studying them as a way to repair human tissue. Some hydrogels are environmentally sensitive and release their water when such things such as pH or temperature change. They’re also used in disposable contact lenses and as water gel explosives.

Across the U.S.

The national science experiment is part of a larger 4-H effort to attract a million new youth to 4-H science, engineering and technology programs by 2013.

“I thought the experiment was very applicable, especially this day in age with water being a hot topic,” said Austin Suggs, a UGA 4-H’er and sophomore from Tifton. “I’m interested in hydrogel use in production agriculture and in industrial use.”

He felt younger scientists could one day find bigger and better ways to use hydrogels.

After performing the experiment, students nationwide were asked to log on to the national 4-H Web site ( to discuss their results.

As of Oct. 9, 299 people had reported to the site. The majority were middle school students, but the ages ranged from kindergarten to the dean of the UGA College of Agricultural and Environmental Sciences. And, 71 percent weren’t 4-H members.

Back in Georgia

Across the state, UGA Cooperative Extension agents performed the experiment with their students. One agent set it up on a square in downtown Covington. Others used 4-H club time to perform it with their kids.

Teachers also got in on the action. Students in Jackson County asked their teacher if they could take diapers home to show the experiment to their families.

Georgia state 4-H director Bo Ryles will be doing the experiment next week with boys at the Bill Ireland Youth Development Center in Milledgeville. He hopes the goopy hydrogels will pull the boys farther into science.

“We started 4-H there, and we’re a part of their science class every week,” Ryles said. “We’re reaching 80 seventh- and eighth-grade boys with this science program. We know it’s going to be a challenge, but their sense of curiosity is still there.”

(Stephanie Schupska is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)

Stephanie Schupska is the communications coordinator with the University of Georgia Honors College.