In cellulose, glucose monomers are added to produce linear polymer chains that can align side by side, favoring inter chain hydrogen bonding. These inter chain links produce a rigid structure of layered sheets of cellulose. This bulky and inflexible structure not only imparts exceptional strength to cellulose, it also renders it insoluble in water. It is, of course, essential for plants that their main building material does not readily dissolve in water!
