Silicone weather-resistant sealant selection
Publisher: Oriental Rubber Industry Time：2022-3-1 17:43:17 hot:
Silicone structural sealants are further divided into one-component, two-component, acid curing glue and neutral curing glue.
One-component silicone sealant can be directly applied to the bonding between aluminum and glass. It is hydrolyzed by absorbing moisture in the air, and the condensation reaction is cured from the outside to the inside. It is required that the glue room is clean and the temperature is not low. At 23°C, the relative humidity is not less than 40%, otherwise it will affect the curing and reduce the strength of the adhesive layer.
The one-component silicone glue is divided into acid and neutral. When the acid glue is cured, it releases acetic acid, which corrodes the film layer of the coated glass produced by the vacuum magnetic sputtering method for the hidden frame curtain wall. Therefore, neutral silicone should be used. Ketone Structural Adhesive.
The two-component silicone structural adhesive must be added with an accelerant to the base adhesive before use, and fully mixed and coated between aluminum and glass in a special glue machine for bonding and curing. Two-component adhesives are all neutral adhesives.
Silicone structural sealants have a standout feature. That is to say, there is a compatibility problem between the glue and the bonded aluminum, glass, and foam strips, and a compatibility test is required, which cannot be done in China for the time being. If the results of the compatibility test show that the structural adhesive and the three materials are incompatible, even during the bonding process, various strength indicators at that time meet the requirements. After half a year or a little longer, the silicone structural adhesive will begin to discolor and deteriorate into a liquid state and lose its bonding ability, and the glass will fall down, causing serious consequences. Therefore, in order to ensure the long-term bonding ability of silicone structural adhesives, compatibility tests must be done.
