Introduction of construction sealant

The bulk properties depend on the chemical properties and physical structure of the main polymer of the sealant, which can be accurately and repeatedly measured. Process properties refer to the relevant characteristics of the sealant during the manufacturing process. The nature of use (product performance) is self-evident, mainly refers to the comprehensive performance of the sealant from the formation of the cementation process to the formation of the cemented joint. This performance depends on the functional requirements of the building joint for the sealant. Regardless of the building envelope or building interior decoration; whether it is window structure or other forms of enclosure and decoration structure, they can be regarded as unit composition, then each unit will have a seam, which is huge Most require construction sealant to seal and fill. Reasonable design of building joints, understanding of building sealants, reasonable selection of materials and correct construction of building seals are the indispensable whole process of ensuring the success of building joints.

1. Silicone structural sealant
Uses: Mainly used for the structural bonding of glass and aluminum sub-frames (see Figure 1), and also used for secondary sealing of hollow glass in hidden frame curtain walls.
Features: bear wind load, gravity load, high requirements for strength, aging resistance, and certain requirements for flexibility.
2. Silicone weather-resistant sealant
Purpose: The sealing function of the curtain wall joints (see Figure 1) to ensure the air-tightness and water-tightness of the curtain wall.
Features: Need to withstand large changes in the width of the joint, high requirements for elasticity (displacement capacity), aging resistance, no strength, high modulus and low modulus.
3. Ordinary silicone sealant
Purpose: Sealing of door and window joints, external wall caulking and other locations (see Figure 2).
Features: Withstand changes in the width of the joints, and have certain displacement requirements, but no strength is required.

Building sealants mainly include polysulfide sealants and silicone sealants.
(1) Polysulfide sealant
At present, most of the sealants used in construction are two-component polysulfide sealants. The appearance of two-component polysulfide sealant is fine, uniform paste or viscous, so it is usually called two-component polysulfide sealant. Two-component polysulfide sealant and two-component polysulfide sealant are The same product.
(2) Silicone sealant
Some of the sealants currently in use are silicone sealants. Silicone sealant has good UV resistance and stable chemical properties, and is the best anti-aging among existing sealants. It has good compatibility with silicone structural sealant, and is widely used in weather-resistant sealing of building curtain walls.