4. Look at the air bubbles: The main component of high-quality silicone sealant is silicone. The amount of other added materials is very small. The good stability of pure silicone is minimally affected by changes in external conditions during the storage period. When air is mixed in and the glue is ejected, the phenomenon of "snap" and "snap" bubbles occurs. However, because the glue of ordinary quality is not 100% silicone, the additives in the silica gel and the PE soft glue of the bottle may produce a chemical reaction, which will cause the bottle to swell and increase, and the air remaining in the space will penetrate the glue. It will make a gap, and the sound of "pop, pop" will be emitted when glue is applied, which shortens the shelf life. What's more, a few manufacturers deliberately hit the bottom cap on the bottom of the bottle when filling the glue, and air was left in the middle of the bottle, which greatly reduced the amount of glue, and air bubbles from the natural glue were inevitable.

5. Check the curing effect: After applying the glue locally, the user should first check the drying time of the silicone glue in conjunction with the instructions on the product packaging. If the time is too short or the timeout is too much, it indicates that the quality of the silicone glue is defective (of course The influence of environmental conditions should also be considered); then after curing is completed, try the hardness and elasticity of the glue by hand, too hard or too soft glue is not good; then the section of the glue can be cut to check the curing effect inside and outside the glue Are they consistent?

6. Test pull and tack: The tensile strength and peel strength (tack) of the silicone rubber after curing are also different due to the difference in the quality of the silica gel. High-quality adhesive has extremely strong tensile force, large tensile range, and high peel resistance.