Knowledges about neutral silicone sealant

4. What is the cause of wrinkles on the surface of the neutral silicone sealant after curing?

Answer: There are generally several reasons

(1) the expansion coefficient of the substrate is relatively large; 

(2) there is displacement or vibration; 

(3) some low-grade sealant are too thin, and there are less fillers in the sealant and more plasticizers ( White oil), the plasticizer (white oil) evaporates to a certain extent during the curing process of the sealant, which makes the volume of the sealant smaller, so the sealant will shrink and wrinkle; 

(4) If the sealant is too thin, it will be easy to wrinkle after curing. , Thickening the thickness of the sizing can reduce the occurrence of this phenomenon (it is recommended to sizing more than 2mm).

5. What is the reason why the neutral transparent sealant turns yellow?

Answer: The yellowing of the neutral transparent sealant is due to the defect of the sealant  itself, which is mainly caused by the crosslinking agent and the tackifier in the neutral sealant . The reason is that the two raw materials have "amine groups", and the amine groups are extremely easy to cause yellowing, and many high-grade glass sealant also turn yellow due to this. In addition, if the neutral transparent sealant  is used at the same time as the acid glass sealant , it may cause the neutral sealant  to turn yellow after curing; it may also be affected by the long storage time of the sealant  or the sealant  reacts with the substrate.

6. After the neutral sealant cured, there are powdery things on the surface. What is the reason?

Answer: There are generally several situations

(1) The pulverization of the sealant  strip is due to the defects in the raw material selection of the sealant ; 

(2) The raw materials are not uniformly mixed; 

(3) Due to the influence of the construction environment, the dust is more likely to be adsorbed on it. This happens on the surface of the sealant.

7. What sealant is better for aquarium fish tanks? Is there any problem with the glass sealant that has been exposed to water or immersed in water for a long time?

Answer: Most of the market uses high-grade acid sealant make general specifications of aquarium fish tanks. If the width and depth of the aquarium are large, and there are greater requirements for the bonding effect and safety, it is recommended to use the special sealant for the aquarium. The cured silicone sealant will not be affected too much if it is exposed to water or immersed in water for a long time.

8. Why does glass sealant sometimes stick to the fish tank, but sometimes it doesn’t stick well or the fish tank bursts?

Answer: There are several situations that may cause this phenomenon.

 (1) If the size of the fish tank is too large, the pressure after filling the water is too large, and the glass and glass sealant cannot be undertake, which will cause the fish tank to burst. 

(2) The glass and glass sealant have quality problems and incorrect construction methods. 

(3) If air is mixed into the glass sealant plastic bottle, air bubbles will be left on the sealant strip during applying. The place where the air bubbles are generated is naturally thin, and the fish tank will burst after being filled with water and pressure. Therefore, we recommend that the user carefully check whether there are bubbles in the sealant strip after applying the glue. If bubbles are found, they must be re-construction.