II. Construction Reasons

1. Air is wrapped in the gel.
Silicone sealant is generally used to complete the injection work in the construction site, and the working conditions are poor. Workers stand on scaffolding to inject glue, the uniformity of the glue is not easy to grasp, and the air is easily wrapped in the glue seam. After gluing, the surface of the sealant is scraped and pressed, and the finish is smooth. The pads in the glue seams usually use closed polyethylene foam rods, and the air in the glue seams is not easy to overflow. When the air is compressed, the air is compressed, and the outward tension is generated. The sealant seams are generally wider, and the thickness is relatively small, providing weather resistant glue with high displacement capability. The hardness is low and the adhesive is soft before curing.  The swelling tension of compressed air bubbles up the seam slowly.  This phenomenon is more likely to occur in the application of sealants that can provide displacement capacity of seams above (+25%). On the contrary, some sealants with lower allowable displacement have higher hardness and are thicker before curing. The swelling tension of compressed air wrapped in the seam does not easily prop up the rubber to foam. Therefore, the more weatherproof adhesives with high displacement ability can be provided, the more attention should be paid to the uniformity of the adhesives when they are injected.  Generally, vertical seam glue can be applied from bottom to top, which can overcome some foaming phenomena. More importantly, it is the proficiency and responsibility of the operator.

2. Workers'Injection Habits
In glue injection construction, we often find that when workers glue glue, many people like to use soap water, detergent water, washing powder water and other sprayed glue joints, and then use hand to smooth, to ensure that the glue does not stick to hands, but did not expect the water to be absorbed by the foam strip, that is, the water is dry, as