Double-wall glue base material of the heat shrinkable tube with conventional heat shrinkable tube material is the same, is PE, double-wall glue heat shrinkable tube is have more than the seal performance of common heat shrinkable tube originates in the double-wall hot melt adhesive for the inner surface of heat shrinkable tube, while baking double-wall thermal shrinkage tube, the lining of the hot melt adhesive also can form a certain fluidity of molten state, can be full of base material and all of the Spaces left between the protected object. We talked about EVA hot melt adhesive above, and then talk about the PUR hot melt adhesive used in the inner wall of the double-wall heat shrinkable tube.
PUR hot-melt adhesive does not contain water and solvent, and its solid content is 100%. It is a kind of high performance environmental protection adhesive, and it ADAPTS to the need of more and more attention to the environment at home and abroad. Reactive PUR hot-melt adhesive has excellent comprehensive performance compared with ordinary hot-melt adhesive. It has the characteristics of no solvent, high initial viscosity and rapid positioning at assembly time, and also has the properties of water resistance, heat resistance, cold resistance, creep resistance and medium resistance. The sizing temperature (120 ℃) and lower than normal (150-180 ℃), hot melt adhesive can be used for some plastic parts of adhesive, composite, highly modern automated assembly industry preferred.
Compared with other types of hot-melt adhesive, PUR hot melt adhesive has a remarkable feature that it usually does not add additives other than the matrix. This is because as the matrix of the polyurethane resin, in the infiltration, melt viscosity, bonding strength, and other aspects of good comprehensive performance. Therefore, the polyurethane resin can be directly used as hot melt adhesive after being synthesized.
PUR hot melt adhesive has been favored since it was successfully developed more than 20 years ago. It has been increasingly developed in Europe, America, Japan and other industrial countries. Although PUR glue at present in China is still in its infancy, but there have been more and more customers recognize the advantages of PUR glue, but due to technical reasons, severely limits the development of domestic PUR glue, the PUR glue is still mainly rely on imports, domestic when can produce high-grade PUR glue, domestic PUR adhesive application will truly large-scale development.
This is a brief introduction of PUR hot melt adhesive.