Why are certain fabric fibers more absorbent than others? The answer has to do with the chemical processes of molecular reaction and fluid absorption that lie in the combination of water and different fabrics. For example, synthetic and natural fabrics have a different arrangement of molecules that react differently when combined with the molecular structure of water. Invite your child to test this theory and the power of her scientific observation as she compares rates of liquid absorption with nylon (a synthetic material) and cotton (a natural fiber).
Have your child pour water into the large glass until it is ¾ full.
Ask him to saturate the wool sample with water.
Invite him to pull one corner of the cotton sample into the small glass, so that it is resting on the rim.
The experiment should be left in place for about 12 hours.
Encourage your child to observe what has occurred. If the experiment went as planned, some of the water probably flowed from the larger glass into the smaller glass.
Repeat steps 1 through 4 with the nylon sample.
Ask your child to notice the results. Which fabric produced the most water in the smaller glass? Which fabric produced the least?
What has this experiment taught your child about the properties of synthetic versus natural fibers? Natural fibers tend to be more absorbent than synthetic ones. Cotton, for example, has more naturally occurring places that can form bonds with water molecules. This means that it can absorb a significant amount of water, about 25 times its weight! Nylon, on the other hand is not hydrophilic (a highly absorbent fiber), and can only hold about 10 percent of its weigh tin water.