Effect of dryness of bonding surface on hot melt glue effect and countermeasures

1. Effect of moisture on hot melt glue bonding effect

Moisture is a potential destructive factor in the bonding process. When the bonding surface contains moisture, the bonding effect of hot melt glue will be greatly reduced. This is because moisture will weaken the intermolecular force between hot melt glue and the surface of the material, reducing the bonding strength. In addition, moisture may also cause premature curing or incomplete curing of hot melt glue, resulting in defects such as bubbles and cracks in the bonding layer, which in turn affects the stability and durability of the bonded parts.

More seriously, if the bonding surface is in a humid environment for a long time, the hot melt glue may gradually lose its viscosity due to absorbing too much moisture, and eventually lead to bonding failure. This situation is particularly common in the manufacture of outdoor equipment and products in humid environments.

2. Countermeasures to ensure that the bonding surface is dry
Pre-treat the bonding surface: Before bonding, the bonding surface should be pre-treated to ensure that it is clean, dirt-free, dry and water-free. This usually includes using an appropriate detergent or solvent to remove contaminants such as oil and dust, and wiping it clean with a clean cloth or paper towel. For the bonding surface that has just been cleaned, wait for it to dry naturally or use tools such as a hair dryer to accelerate the drying process.
Control environmental conditions: The bonding operation should be carried out in an environment with low relative humidity and suitable temperature. Excessive humidity will prolong the drying time of the bonding surface and even cause bonding failure. Therefore, when performing bonding operations in humid seasons or humid environments, measures should be taken to reduce the ambient humidity, such as using a dehumidifier, increasing ventilation, etc.
Choose the right hot melt glue: Different types of hot melt glues have different sensitivities to moisture. When choosing hot melt glues, products with low moisture sensitivity and good water resistance should be selected according to specific application scenarios and requirements. This can reduce the impact of moisture on the bonding effect and improve the stability and durability of the bonded parts.
Monitor the bonding process: During the bonding process, pay close attention to the drying of the bonding surface. If moisture residue or moisture is found on the bonding surface, the bonding operation should be stopped immediately and the bonding operation should be carried out after the bonding surface is completely dry. At the same time, the quality of the bonded parts should be checked regularly to ensure that they meet the design requirements and usage needs.