How to make hot melt glue?

Question

This glue is used in making plywood.

Answer 1

You don't make it, you buy it at the hardware store.

Answer 2

Hot melt glues, and most adhesives for that matter are generally made up of rubber (such as natural or butyl rubber), tackifier resin (from hydrocarbons) and plasticizer (usually an oil, but could also be polybutadiene). The ratio of the three ingredients is vital to the final properties of the glue and is a closely guarded trade secret for any adhesive manufacturer. Polymer such as polyethylene may also be added to create a stiffer glue.