What is Polyurethane PUR Hot Melt Adhesive？
PUR hot melt is different than traditional hot melt. It is dispensed in very much the same way, the adhesive is heated to a liquid state and applied to your materials and cools to ‘stick’ them together. But…this is where PUR hot melt is special. As it cools, PUR hot melt reacts with moisture in the air and changes chemically to create an incredibly strong bond. This bond then continues to strengthen over 24-48 hours until it is fully cured and super strong.PUR hotmelt adhesives meet increased requirements with regard to strength, water and heat resistance as well as chemical resistance.
Advantages of PUR hot melt adhesive
(1) Solvent-free, one-component type.
(2) It can be glued at low temperature. The melting temperature of the polyurethane reactive hot-melt adhesive is lower than that of the general hot-melt adhesive, and it can be used at 120-150 °C.
(3) Good operability. The two adherends can be fixed in a short time to improve work efficiency.
(4) The pot life is long, the pot life can reach 16h at 150℃ and 3 days at 90℃.
(5) Excellent heat resistance, cold resistance, water vapor resistance, chemical resistance and solvent resistance
Drawbacks of PUR Hot Melt
Up until this point it’s been all roses and unicorns but we’re here to tell you there are some drawbacks to PUR hot melts. Remember that chemical change we talked about that gives PUR its strength and durability? Well, that chemical change that makes PUR the “Andre the Giant” of hot melt adhesives also comes with some downsides.
Because PUR hot melt reacts with moisture in the air, it must also be protected from moisture before it is used. This means it has to be packaged in air tight cartridges or foil and cannot be exposed before use. It also means that PUR hot melt carries a shelf life of around 12 months (traditional hot melts have none).
PUR hot melt application
PUR hot melt adhesives can bond not only porous materials, such as foam, ceramics, wood, fabrics, etc., but also materials with smooth surfaces, such as steel, aluminum, stainless steel, metal foil, glass, plastic, leather and rubber.PUR hot melt adhesives are now known to be widely used in packaging, wood processing, automobiles, textiles, electromechanical, aerospace and other national economic fields
winlong is the largest hot melt adhesive manufacturer in China, if you need to buy pur hot melt adhesive, please contact us by email:iwgytn@gmail.com
