This clip starts with a brief introduction into what polymers are and lists examples of both natural and synthetic polymers. It then goes on to describe what a smart polymer is, before focusing on one type of superabsorbent, hydrogel. It gives an interesting example of how this product, which is used in nappies, has a transferable use in fighting fires due to its ability to hold large amounts of water.
Students could investigate the properties of hydrogels as used in hair gel, nappies and plant water-storage crystals. Salt could be added to hair gel and the shrinkage and drying up of the gel observed. Known masses of the absorbent granules used in nappies or as plant water-storage could have water added and the amount of water they can hold measured. To understand what is going on, students will need to have understanding of ionic and covalent bonding, reversible reactions and acids and bases.