Can hot melt glue sticks be used on aluminum-plastic composite pipes?


The bonding objects of hot melt glue sticks for aluminum-plastic pipes are high-density polyethylene (such as 5000s, 2480) or cross-linked polyethylene (xLPE) and aluminum. The bonding process is stopped simultaneously with the composition of the outer and inner tubes and aluminum tubes (one-step Process), perhaps first forming the inner tube, squeezing the inner layer of glue, wrapping the aluminum foil into a tube, and then extruding the outer layer of glue and the outer tube (two-step process).

High-density polyethylene is a non-polar linear crystalline polymer material with a density of 0.941-0.9659/cm3, a crystallinity of 80%-95%, and a small degree of branching (5-7 in 1000 carbon atoms cH,), the average relative molecular mass is generally 1 assumed to be 300,000, and the melting point is 126-137°C, which is difficult to be bonded by adhesives at room temperature. Traditionally used EVA, polyamide, and polyurethane hot-melt glue sticks have poor adhesion, poor heat resistance, and the extrusion process does not meet requirements.