In service conditions, glue and sealing glue should be used in a certain environment, and the working conditions have an important impact on the bonding performance. In the use conditions, there are stress conditions, ambient temperature and humidity, chemical media conditions, outdoor conditions, etc. When the adhesive is subject to peeling force and uneven pulling force, the adhesive with good toughness can be selected, such as rubber glue, polyurethane glue, etc; When subjected to uniform pulling force and shear force, adhesives with higher hardness and strength can be selected, such as epoxy adhesive and acrylate adhesive.

In the use of glue, too much glue will make the macromolecules in the glue crowded together, and there will be no good tension between the macromolecules. At the same time, the water between polymer bodies is not easy to volatilize. This is why "the thicker the adhesive film, the worse the adhesive effect". If the amount of glue is too much, the large amount of glue plays a role of "filling" rather than bonding. The bonding between objects depends not on the adhesive force of the glue, but on the "cohesion" of the glue. If it is not water-soluble, the principle is the same. It is just using other solvents instead of water.