Hot-melt glue is a form of thermoplastic adhesive that is commonly sold as solid sticks to be applied using a glue gun (wiki link). The hot glue gun uses a heating element to melt the hot-melt glue, which the then is pushed through the nozzle either with a trigger mechanism, or by finger pressure. The thermoplastic adhesive is initially hot enough to burn the skin. The hot adhesive is tacky when hot, but solidifies in a few seconds up to a minute. In industrial application hot adhesive is often sprayed and dipped Common use thermoplastic adhesive are made of ethylene-vinyl acetate - lowperformance, the low-cost and most common material. The common shape of the hot adhesive is sticks that vary in length, width. Typically, thermoplastic adhesive are waterproof and able to withstand chemical treatments. Resistance to water and solvents is critical in some applications: in textile industry, non-toxicity and absence of odors is important for food packaging.
To ensure the best bonding results, a compatible hot melt adhesive is essential for each best glue gun and application. The chemical composition of hot-melt glue varies, most are made of ethylene-vinyl acetate copolymers, polyolefins or polyamides. Thermoplastic adhesive is often more convenient both in for hobbyists and industrial users. It has no volatile organic compounds, safe for health and ready to work in a few seconds. Of course, there are some disadvantages, including heating of the glued surface (some substrates like foam in air modeling are sensitive to high temperatures), bond strength loosing at higher temperatures, etc. Hot glue stick are great for wood, ceramic, porous substrates, metals, plastics, and so on. They are ideal for a wide range of arts and crafts ideas.