Why does paper wrinkle or become wavy after being wet by water/liquid?

Question

I'm just curious. My textbook got wet, and the paper is all wavy and 'wrinkly'. It's quite impossible to straighten it out as well. heh, just curious. I don't plan on fixing my textbook. ^^

so, Why does that happen?

Answer 1

When a paper becomes saturated with water, it in turn becomes "soggy" making it more conformable to its environment. Water disrupts the molecular structure by imposing on the conformable paper its hydrogen bonds.

The hydrogen bonds are weak bonds that the water uses to keep itself together. You witness hydrogen bonding when you see a water droplet form on any surface rather than form a thin lining over a surface (water tension).

As the hydrogen bonds attempt to reestablish their lost equilibrium, they further stretch the paper outward.

Water has many properties that make it a unique substance. It is amazing what someone can learn in an AP Biology course :p