How Much Do You Know About PUR Hot Melt Adhesives?

While talking with others about PUR hot melt adhesives, I found that they don’t really understand PUR hot melt adhesives, and even the difference between PUR hot melt adhesives and hot melt adhesives was not particularly clear for them.

PUR is called moisture curing reactive polyurethane hot melt adhesive. The main component is an isocyanate-terminated polyurethane prepolymer. PUR adhesives produced by PUR hot melt adhesive machine contain polar and chemically active urethane or isocyanate groups in the molecular structure, and materials containing active hydrogen, such as wood, leather, fabrics, paper, ceramics and other porous materials and plastics, metals, glass, rubber, etc. Surface smooth materials have excellent adhesion.

PUR hot-melt adhesive is heated to melt into a fluid for coating under the condition of inhibiting chemical reactions; the adhesive layer condenses after two kinds of adherends are cooled together to play an adhesive role; afterwards, the moisture and the moisture attached to the surface of the adherend reacts with it and expands the chain to generate a high-molecular polymer, which significantly improves the adhesion, heat resistance, and low temperature resistance. PUR hot melt glue laminating machine plays an important during the process.

The scope of hot-melt adhesives is very wide, and PUR is one of them. Most of the hot-melt adhesives are heated and can be reheated after bonding. It is reversible. During the heating operation, it will react with the moisture in the air after bonding and it will be irreversible after the reaction (that is, the heating will not melt). So PUR is more resistant to high and low temperatures.

PUR is characterized by high cohesive strength and high bonding strength, high temperature and low temperature resistance, performance far exceeds ordinary hot melt adhesive. The difference between the two is mainly the use of equipment, and the storage environment and method. PUR must be isolated from the air, and it will react with the moisture in the air. PUR hot melt adhesives are now more popular adhesives and widely used in various fields.