Key points and precautions for the use of polyurethane adhesives

To ensure the full performance of polyurethane adhesives and their safe and effective use, the following points need to be particularly noted:

 

1. Surface treatment is crucial: The cleanliness and dryness of the surface of the adherend directly affect the final bonding effect. Diversified and thorough removal of contaminants such as oil stains, dust, moisture and rust on the surface. When necessary, appropriate solvents can be used for cleaning or physical grinding treatment can be carried out to increase the surface roughness and enhance the bonding strength.

 

2. Control of environmental temperature and humidity: The curing reaction depends on environmental humidity and temperature. Low humidity will significantly slow down the curing speed. Too low a temperature will also slow down the curing process, while too high a temperature may cause the surface of the glue to form a skin too quickly, affecting the curing of the deep layers inside. Generally, it is recommended to carry out construction within an appropriate range of temperature and humidity. In a very dry environment, artificial humidification may be required to promote curing.

 

3. Correct gluing and bonding methods: Select appropriate gluing tools based on the shape and size of the joint to ensure that the glue is evenly and continuously applied to the bonding surface. For large-scale construction, it is necessary to pay attention to the open time (i.e., the allowable time interval from applying the adhesive to bonding) to avoid bonding after the surface is dry, which may affect the effect. Applying appropriate pressure helps to expel air bubbles and form a denser adhesive layer.

 

4. Waiting for complete curing: Surface drying (the surface is not sticky to the touch) and initial curing (with a certain strength) do not mean that the glue has fully reached its final strength. Complete curing usually takes 24 hours or even longer, depending on factors such as the thickness of the adhesive layer and environmental conditions. Before reaching full strength, the bonded area should be avoided from being subjected to full load.

 

5. Safe Operation and Storage: Use should be carried out in a well-ventilated environment to avoid prolonged inhalation of volatile substances. Wear appropriate protective gloves to avoid direct skin contact with the uncured adhesive. If accidentally contaminated, it should be wiped off promptly with an appropriate cleaning agent (such as acetone, which should be used with caution), and then washed with soapy water. The product should be stored in a cool and dry place, with the container kept sealed to prevent moisture absorption and deterioration. Keep away from fire sources and children.