How do these two molecules interact?

When cellulose is suspended in water, the water molecules do not discriminate against the cellulose molecules and include them in the chain. This creates a mass of watery cellulose.

Papermakers catch this mass of watery cellulose in a screen, allow the excess water to drain off and press the soggy cellulose, which is now called 'waterleaf' paper, flat. As the rest of the water evaporates out of the 'paper', the chain effect transfers to the cellulose alone and the cellulose takes on a solid form.