The advent of WWII led to great shortages in many raw materials that were used in our traditional glues. Synthetic rubber was the first major leap forward and this spawned the new technology that led to synthetic adhesives. Before we head off into listing glues and their uses I thought it might be pertinent to cover the ins and out of how glue bonds to wood. Currently there are about 1500 different adhesives in the market. Out of this list there are only a few that are suitable for wood.
Wood is a complex mixture of cellulose, organic chemicals and water.
Most of the actual structure of a tree is cellulose and this is formed by nature into an intricate matrix that gives it its strength, rigidity and its elasticity that we know. It is this mixture of natural chemicals that gives the wood its smell, its colour and in some cases a resistance to rot. The glue links to the structural fibres, keying into the areas that once carried the water. When the glue has been absorbed into the wood it quickly hardens and mechanically attaches itself to the wood. This action happens to both surfaces and the thin line of glue between the two pieces of wood forms a bridge that links the two together.