Weather Sealant vs. Structural Sealant
Professional Solutions for the Middle East: With extensive experience in UAE and Saudi markets, Weidu (WD) provides customized sealant solutions, from product supply to technical support.
Choosing the right sealant is critical for the durability of any construction project. Performance varies based on formulation and grade. To ensure long-lasting results, factors such as substrate compatibility, environmental impact, and bonding requirements must be considered. This guide explains the key differences between Silicone Weather Sealant and Structural Silicone Sealant.
What is Silicone Sealant?
Silicone sealant is composed of silicone polymers, crosslinking agents, coupling agents, and reinforcing fillers. Because the main chain and functional groups of silicone polymers have very high bond energy, they are difficult to destroy. This provides exceptional resistance to UV rays, extreme temperatures, and moisture, ensuring superior weatherability and stable adhesion.
1. Silicone Weather Sealant
Weather-resistant silicone sealants feature a flexible long-chain structure with a high displacement capacity (typically 25% to 50%). Designed to withstand long-term sunlight and complex weather conditions, they are primarily used for sealing joints in doors, windows, facades, and various outdoor architectural structures.
In regions with tropical desert climates like Saudi Arabia and the UAE, sealants face extreme tests: summer temperatures reaching 50°C, winter humidity dropping to 13%, and constant high UV radiation. Standard sealants often fail under these conditions, leading to rapid aging or leakage.
WD-866 Professional Weather Sealant
Engineered for temperatures from -40°C to +150°C. It forms a dense waterproof layer that handles thermal expansion and structural movement, with a service life exceeding 15 years.
2. Silicone Structural Sealant
Structural silicone sealants are designed with high cohesive strength and a complex cross-linked network. They are engineered to handle structural loads and high-elasticity requirements, such as in glass curtain walls and stone or metal panel systems.
WD-986 Structural Silicone
Features an ultimate tensile strength of 1.1Mpa and 460% elongation. It is the ideal choice for structural bonding in skylights, curtain walls, and metal frames where durability and load-bearing are paramount.
Quick Comparison Table
| Feature | Weather Sealant | Structural Sealant |
|---|---|---|
| Adhesion | ||
| Load-Bearing Capacity | ||
| Anti-aging & Weatherability | ||
| Movement Capability | ||
| Application | Facades, window frames, sunrooms, expansion joints. | Curtain wall frameworks, stone facades, insulated glass secondary sealing. |
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