Hot melt adhesives are generally 100% solid adhesive formulations based on thermoplastic polymers. The best-known types are hot glue sticks, EVA, PO, Polyolefin, PUR, PolyUrethane and rubber based PSA
Shaped hot melt adhesives
Hot melt sticks are widely known for hobby applications with a glue gun and a typical 11mm diameter glue cartridge. Cartridges also come in other diamaters, such as 7mm, 15mm, 18mm and 43mm. These are almost exclusively EVA, Rubber-based and Polyolefin adhesives.
EVA HOT MELT
EVA hot melt adhesive started the industrial hot melt revolution. EVA hot melt replaced dangerous solvent glue and slow drying water-based glue. The advantage of a hot melt is that it contains no solvent and dries much faster than a water-based adhesive.
Polyolefin HOT MELT
Polyolefin replaces EVA hot melt adhesives in many applications. The Polyolefin polymer provides often a stronger bond and higher thermostability than the EVA polymer.
PUR HOT MELT
Due to the success of EVA hot melt, the industry got used to the idea that adhesives can be heated prior to processing, and when cooled, realize a rapid “adhesion”. This basicly can be applied to many polymers, the Polyurethane or PUR hot melts were born.
PSA is an abbreviation for “Pressure Sensitive Adhesive” and are often used for applications such as self adhesives tape, and self adhesive labels. PSA hot melt adhesives are frequently used for many other materials as well, where a double-sided tape or laminate can be applied, but then directly by inline application of hotmelt on for example foam, plastics or devices.
Organic HOT MELT
There are several thermoplastic and PSA hot melts that have an organic base of 30%-70%. For all kind of applications packaging hot melt, assembly hot melt and also self-adhesive PSA hot melts.