Industry dynamic

How to use silicone sealant and matters needing attention

2022-08-05

The silicone sealant is used as follows:

1. The one-component product can be operated directly with a glue gun; the two-component silicone glue needs to be mixed evenly in proportion.

2. Clean the surface of the bonding object, and clean up oil, rust, etc. If necessary, professional cleaning agents can be used, and then appropriate sanding with sandpaper can be used to improve adhesion.

3. Apply the silicone sealant evenly to bond. When bonding the two surfaces, squeeze out the air to avoid affecting the curing effect.

4. Curing at room temperature, and the next step can be performed after a period of time.

5. Wipe off the excess adhesive with a rag or paper towel, and clean it with a blade after curing.

 

The following operations should be avoided during the use of silicone sealants:

1. Not suitable for long-term immersion in water, so as not to affect the adhesion of the adhesive.

2. It cannot be used on surfaces that are too wet or prone to frost, and cannot be bonded normally.

3. One-component silicone sealant cannot be cured in a completely sealed environment, and may not be completely cured.

4. The surface of the substrate must be kept clean and dry, otherwise it cannot be firmly bonded.

5. Do not use inferior adhesives, so as not to corrode other parts.

 

The curing of silicone sealant has environmental restrictions. Generally speaking, in the range of 5~40℃, normal construction can be carried out. When the surface temperature of the substrate is higher than 50℃, please stop the construction. If the construction is continued at this temperature, although the curing speed will be accelerated, at the same time, the small molecular products will not be discharged in time, resulting in the formation of bubbles. When the temperature is too low, the curing speed will slow down, shrinkage may occur, and the adhesive layer will be out of shape.

Silicone sealants are not suitable for all occasions, such as places that have been soaked in water for a long time, frosted or too humid, and the surface of the substrate is not clean enough, and it is not easy to bond with oily materials.

 

The quality inspection of silicone sealant should be considered from the following aspects:

1. Performance

When purchasing an adhesive, read a series of properties at first glance to see if the performance of the adhesive meets the needs of use. Looking at the shelf life, the better the adhesive, the longer the storage time in a specific environment.

2. Look at the production date

Each batch of adhesive has a fixed production date. Expired products cannot be purchased. After the expiration date, all aspects of the adhesive will decline, which is not suitable for long-term use.

3. Try by hand

Take the overflowing adhesive in your hand, pinch and pull, if the elasticity and softness are good, the quality is good, if it feels hard and brittle, there may be some quality problems, and you need to be vigilant. At the same time, observe whether there are particles and bubbles in the colloid. If there are, it will affect the mechanical properties of the colloid after curing.