Ans.

Superglue and PVA glue both use polymerisation for adhesion. Polymerisation is a chemical reaction, where the sharing of electrons allows some types of molecule to join together, forming long chains called polymers. Superglue contains a compound called ethyl 2-cyanoacrylate, which reacts with water to cure (ie turn from a liquid into a solid). Usually there is a very thin layer of water present on most surfaces – condensed water vapour from the air – making superglue effective on almost any type of surface. PVA (polyvinyl acetate) glue is water-based, and is commonly used for sticking wood together. Water in PVA intertwines the fibres of wood with the polyvinyl acetate, eventually evaporating and leaving behind a bond stronger than the material itself.