Causes And Solutions Of Foaming Of Weather Proof Silicone Sealant

The reasons for the blistering of weather proof Silicone Sealant during construction are multifaceted and complex, making it difficult to determine a method or result that causes the blistering. The inhumane changes in climate, environment, working conditions, and other factors have a significant impact on the curing quality of weather proof Silicone Sealant. Therefore, the limitations of the environment and working conditions of weather proof Silicone Sealant determine the main reason for the production of foam. Discuss with everyone the reasons for weather proof Silicone Sealant.

1. When injecting weather proof Silicone Sealant , wrap the air around it.

Organic weather proof Silicone Sealant are generally injected into construction sites under harsh working conditions. Workers stand on scaffolding and inject glue, which makes it difficult to grasp the uniformity of the glue and can easily wrap air in the glue. Therefore, the higher the displacement capacity of the weather proof sealant, the more attention should be paid to the uniformity of the sealant when injecting it. Vertical adhesives can generally be sized from bottom to top to overcome water bubbles. More importantly, the proficiency and sense of responsibility of the staff.

2. Moisture at the interface of plastic injection

Working in the wilderness, especially in the southern summer, it rains almost every day. After rain, if the moisture inside the interface is not dry, directly inject glue. When the sun shines on the bonding equipment and adhesive, the temperature in the interface will rise, the moisture in the sealant will not harden when evaporating, and the soft sealant will expand. Sometimes the polyethylene foam pad will also bubble the gelatin when it is wet. It is difficult to overcome this situation in hot summer engineering.

3. When using glue, avoiding exposure to the sun can overcome the phenomenon of water bubbles. Specific method: In the morning, inject glue to the west or north of the building, and in the afternoon, inject glue to the east or south of the building. After injecting glue, the glue will solidify for a period of time, and the surface has already formed skin. Under the sunlight, it has a certain resistance and can overcome some water bubbles.

4. The surface temperature of the substrate is too high.

The temperature of the sealant material during silicone curing should not exceed 50. This conclusion has been recognized by most silicone rubber manufacturers. When the surface temperature of the substrate exceeds 50, injecting sealant will cause the gelatin to bubble and impact the weather resistance gap of the metal panel curtain wall. On a hot construction site, the surface temperature of metal plates, especially aluminum plates, may reach 80 when exposed to sunlight, and injecting glue can easily cause the glue to bubble. Therefore, it is necessary to choose the afternoon or cloudy weather in the second half of the year to improve the above situation.

5. Large temperature difference between day and night, large thermal expansion of interface

This situation is more likely to occur when injecting sealant into aluminum curtain walls. Aluminum plate is a material with a high coefficient of linear expansion. In northern China, there is a large temperature difference between day and night in spring or autumn. When the sun shines directly on the aluminum plate at noon, the surface temperature of the aluminum plate drops to 60-70, and at night, the temperature drops to about 10. The thermal expansion and cold shrinkage of the large aluminum plate are also large, and the interface displacement is also large. After the weather proof sealant is sewn together,

6. The climate in northern spring is dry

Silicon sealant needs to utilize moisture in the air, undergo chemical reactions, and react with elastic sealing materials. The magnitude of humidity in the air is closely related to the curing rate. The climate in northern China is dry in spring, and the curing time of silicone sealant is long after injection. Non curing silicone sealant is easily affected by the external environment, providing opportunities for various foaming phenomena