How Do Disposable Diapers Absorb?

Just recently, Lisa Nowak, the NASA astronaut, drovewater outside the molecule. This mixture of water and
900 miles wearing a diaper designed for space travel.crystals turns into a gel like substance. In fact, a pound
Have you ever wondered how it really works?of crystals can absorb about 50 gallons of water.
The design for this astronaut incontinence product isSince urine contains water and salts, and these salts
similar to what you see on the supermarket shelf. Theimpede the performance of the original sodium
astronaut design resembles a pair of bike pants. Whilepolyacrylate. Scientists have modified the polymer to
retail consumers have a choice of diapers with tabs,counteract the affects of the salts in urine.
pull ups, undergarments and liners.The chaise of a diaper is usually made of plastic or a
If you cut open a diaper, you will notice a crystal likespecial designed cloth like paper that gives a diaper its
substance called sodium polyacrylate and usually calledshape and contains the wetness. The next layer wicks
super absorbent polymer or SAP. These crystalsthe wetness away from the skin. Some of these
have a similar feel as fine sand. This polymer waslayers have special one way funnels that the wetness
created by the scientists from the Dow Chemicalmoves in one direction and not resurface back to the
Company.skin. Finally the wetness drawn into the absorbent inner
When these crystals are exposed to water, the watercore and locked in. This inner core is a combination of
drawn inside the sodium polyacrylate molecule throughpaper cellulose fluff and the sodium polyacrylate
osmosis. The polymer will continue to absorb watercrystals.
until the water inside the molecule is equivalent to the