WEBVTT - How do polymer crystals work, and why do they absorb so much water?

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<v Speaker 1>Welcome to Brainstuff from house stuff works dot com where

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<v Speaker 1>smart happens. Hi Marshall Brain with today's question, how do

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<v Speaker 1>polymer crystals work and why do they absorb so much water?

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<v Speaker 1>If you have an infant or a toddler in diapers,

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<v Speaker 1>you may occasionally notice these clear crystals sticking to his

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<v Speaker 1>butt when you take the diaper off. These are called

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<v Speaker 1>polymer crystals. Polymer crystals are one of those special things

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<v Speaker 1>that are almost magical if you can watch them work.

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<v Speaker 1>Polymer crystals get very similar to a gelatin dessert when

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<v Speaker 1>you put water on them. One of their major uses

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<v Speaker 1>is indisposable diapers, where they're referred to as super absorbent polymers.

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<v Speaker 1>This is the thing that allows a diaper to absorb

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<v Speaker 1>lots and lots of urine without ever leaking. The polymers

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<v Speaker 1>allow for thinner and lighter disposable diapers because they absorb

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<v Speaker 1>so much water. Add water to the white crystal flakes,

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<v Speaker 1>and they absorb many many times their size. As the

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<v Speaker 1>polymer gel forms, one pound of crystals holds about fifty

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<v Speaker 1>gallons of water. The gel that forms swells by absorbing

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<v Speaker 1>thirty grams of water for each gram of crystals construction workers, bicyclists,

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<v Speaker 1>and motorcyclists can often be seen wearing cloth headbands or

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<v Speaker 1>wearing a cloth collar around their neck. The crystals are

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<v Speaker 1>sewn into a pouch in the cloth. The cloth item

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<v Speaker 1>is then soaked in water for several hours. That tiny

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<v Speaker 1>handful will swell up too many times its size and

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<v Speaker 1>provide moist evaporative cooling for the person who's wearing it.

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<v Speaker 1>Florists also use these crystals as a dirt free way

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<v Speaker 1>to store water and keep cut flowers fresh for a

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<v Speaker 1>long time. It takes about forty five minutes to hydrate

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<v Speaker 1>the typical headband or collar for duration ahead of time

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<v Speaker 1>isn't necessary, but it does help extend the cooling time.

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<v Speaker 1>The same polymer crystals can be rehydrated many times. They'll

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<v Speaker 1>dry out and form the crystals again, and then re

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<v Speaker 1>expand when they're rewetted. Be sure to check out our

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