According to their applications, sealants can be broadly categorized into the following five types: silicone structural sealants, silicone weather-resistant sealants, ordinary silicone sealants, secondary silicone sealants for insulating glass, and silicone sealants for special applications. 


1. Silicone structural sealant 

Purpose: Primarily used for structural bonding between glass and aluminum sub-frames, and also for secondary sealing of insulating glass in hidden frame curtain walls. 
Characteristics: It is designed to withstand wind and gravity loads, with high requirements for strength and aging resistance, and certain elasticity requirements. 


2. Silicone weather-resistant sealant 

Purpose: Seam sealing function (see Figure 1), ensuring air tightness, water tightness, and other properties. 
Characteristics: It needs to withstand significant variations in joint width, with high requirements for elasticity (displacement capacity) and aging resistance, but not for strength. Both high and low modulus are acceptable. 


3. Ordinary silicone sealant 

Purpose: Sealing of door and window joints, exterior wall joints, and other locations. 
Characteristics: Able to accommodate changes in joint width, requiring a certain degree of displacement capacity, but not strength. 


4. Secondary silicone sealant for insulating glass 

Purpose: Secondary sealing of insulating glass to ensure structural stability of the insulating glass. 
Characteristics: High modulus, not too soft, some have structural requirements. 


5. Special-purpose silicone sealant 

Purpose: For seam sealing with special requirements, such as fire resistance and mold resistance. 
Characteristics: It must possess certain special properties (such as mildew resistance, fire resistance, etc.) 


Through the above introduction, I believe everyone has understood the various applications of silicone sealant. Based on the characteristics of different applications, the correct selection of sealant should be made. Silicone sealants for different applications have their own unique performance characteristics. Generally, they cannot be used interchangeably. For example, using weather-resistant sealant instead of structural sealant, or using door and window sealant instead of weather-resistant sealant, may lead to serious quality and safety accidents in the project.