天然纤维里的植物纤维和动物纤维都易吸水。当回搬运工：
"The reason why wetting your hair or cotton destroys any shape you've given
it is precisely because it absorbs water. The water then chemically bonds to
the molecular chains, effectively partially dissolving them. Because the
atoms within the chains are now bonded to the water, the links between them
become weakened. That allows them to start slipping past one another again.
In the case of hair, it has a natural shape that is a result of the precise
chemicals it is made of. That is the lowest energy state for the hair. If
the molecular chains are free to slip around they will eventually "fall"
into that shape, and because it is a low energy shape you then need to put a
lot of energy in to get them back out of it. That energy normally comes on
the form of pressure, but if you aren't applying pressure to the hair while
it is wet it's just gonna stay in the low energy natural shape, the way
nature intended it."
