Although many specifications are listed on the technical data sheet (TDS), the diameter of glue sticks is the most important specification for a successful glue gun application. Most glue guns are designed to accept glue sticks with certain diameters. Although a tolerance is permitted for the glue sticks, e.g. 11-12 mm, a consistent diameter is always desired for long term processing. Glue sticks with a larger diameter may not fit properly and may not be smoothly inserted into the gun. Conversely, a smaller diameter will be too loose upon triggering the stick. An accurate diameter of glue stick will provide a consistent adhesive output without damaging the glue gun. An inconsistent output, or bead size, can also result in poor bond strength.
All the polymeric materials impart a certain degree of shrinkage upon cooling from high temperatures to low temperatures. When hot melt adhesives are made in a mixer at elevated temperatures, the polymeric molecular chains are fully extended and orientated. Upon cooling at the holding tank before extrusion, the polymeric molecular chains can relax and coil back to a certain extent. When the adhesive is extruded… Read Article >>
Key Requirements for Hot Melt Glue Stick Production
- by Pierce Covert, Glue Machinery Corporation